Browsing by Author "Carroll, Jeffery A."

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Decomposing variation in ex vivo leukocyte responses and measures of metabolic status in multiparous holstein cows during the transition period
(2015-05) Sellers, Matthew Daniel; Ballou, Michael A.; Carroll, Jeffery A.; Jackson, Samuel P.; Trojan, Sara J.; Rakhshandeh, Anoosh
For the commercial dairy cow, the transition period, from dry off through 30 days in milk, represents a time of elevated metabolic and physiologic stress. This metabolic and physiologic stress is attributable to multiple sources, including the metabolic demands of lactation, the physiologic stress of parturition, and multiple regroupings and pen moves during the transition period. The stressors also contribute to generalized immunosuppression during the transition period. As a consequence of these stressors and this generalized immunosuppression, the transition period is characterized by increased incidences of metabolic diseases including ketosis, fatty liver, displaced abomasum, milk fever, and retained placenta, and infectious diseases such as mastitis and metritis. Disease incidence during the transition period, however, is highly variable both among and within dairy herds. A data simulation was conducted with the intent of illustrating the utility and robustness of some common effect size statistics and two studies were conducted with the aim of decomposing variation in ex vivo leukocyte responses and measures of metabolic status in multiparous Holstein cows during the transition period. In the first study, the effects of herd, parity, and the herd x parity interaction on ex vivo leukocyte responses and measures of metabolic status and hematology were investigated. Eight commercial dairy herds in western Texas and eastern New Mexico were included in the study. Peripheral blood samples were collected from 30 clinically healthy multiparous cows per herd. Cows were starting their 2nd, 3rd, or ≥ 4th lactation and were 2-8 days in milk. Leukocyte responses evaluated included neutrophil surface expression of L-selectin, neutrophil oxidative burst capacity when co-cultured with an environmental Escherichia coli, and the secretion of tumor necrosis factor-α and interferon-γ when diluted whole blood was co-cultured with lipopolysaccharide and phytohemagglutinin-P, respectively. Plasma concentrations of glucose, urea nitrogen, non-esterified fatty acids, β-hydroxybutyrate, and haptoglobin were measured. Total leukocyte count and differential were also measured. Effect size estimates for herd, herd x parity interaction, and residual variation were calculated as omega-squared and the intraclass correlation coefficient, and estimates for parity were calculated only as omega-squared. Effect size estimates were classified based on magnitude as either very small, small, moderate, or large based on previous recommendations. Generally, herd, parity, and herd x parity interaction explained a small or very small portion of the total variation in plasma metabolites and hematology, with the exception of plasma β-hydroxybutyrate concentration, where herd explained a moderate amount of the total variation. Parity and herd x parity interaction also only explained a small or vary small portion of total variation in the leukocyte responses that were evaluated. Contrastingly, herd explained a moderate or large portion of the total variation in most leukocyte responses, excepting neutrophil expression of L-selectin. Residual variation, representing variability among cows within herd x parity cohorts, was large for all response variables evaluated. These data suggest that leukocyte responses are more sensitive to herd-level factors than indicators of metabolic status or hematology. Large residual variation also suggests that a better understanding of what contributes to variation among cows in these cohorts is needed, and may lead to improvements in health of periparturient cows. In the second study, 24 multiparous Holstein cows from a single herd were sampled throughout the transition period in order to estimate effect sizes associated with variation between sampling days, variation between cows, and residual, within-cow variation for ex vivo leukocyte responses and measures of metabolic status. Peripheral blood was collected from cows at dry off (approximately -60 days in milk), move to close up pen (approximately -30 days in milk), calving, and 14 and 28 days in milk. Leukocyte responses evaluated included neutrophil surface expression of L-selectin, neutrophil oxidative burst capacity when co-cultured with an environmental Escherichia coli, and the secretion of tumor necrosis factor-α and interferon-γ when diluted whole blood was co-cultured with lipopolysaccharide and phytohemagglutinin-P, respectively. Plasma concentrations of glucose, urea nitrogen, non-esterified fatty acids, β-hydroxybutyrate, and haptoglobin were measured. Total leukocyte count and differential were also measured. Effect size estimates for between-cow variation and residual, and estimate of within-cow variation, were estimated as omega-squared and the intraclass correlation coefficient, while estimates for between-day variation were estimated only as omega-squared. Estimates were classified as described in the previous study. Effect size estimates for between-day variation were large for all responses evaluated with the exception of whole blood secretion of tumor necrosis factor-α and interferon-γ from stimulated cultures and lymphocyte count, suggesting that these responses are not as sensitive to the physiologic and metabolic stresses of the transition period as other responses evaluated in the study. Between-cow variation was large for whole blood secretion of tumor necrosis factor-α and interferon-γ from stimulated cultures, neutrophil oxidative burst capacity, and total leukocyte and lymphocyte counts, while between-cow variation was small for neutrophil L-selectin expression, neutrophil count, and ratio of neutrophils to lymphocytes. Effect size estimates for between-cow variation were moderate or large for plasma concentrations of non-esterified fatty acids, β-hydroxybutyrate, and urea nitrogen, and were small for plasma haptoglobin concentration. These data suggest that some leukocyte responses may be more largely influenced by genetic and epigenetic variation than others, resulting in larger between-cow variation. Residual variation, representing heterogeneity of response patterns among cows throughout the transition period, was large for all response variables measured. Further identification of factors that contribute to heterogeneity of responses during the transition period may allow for more effective management of cows during this time.
Dehydrated citrus pulp alters feedlot performance of crossbred heifers during the receiving period and modulates physiological and acute phase responses and metabolite concentrations
(2012-12) Cribbs, Joshua; Rathmann, Ryan J.; Johnson, Bradley J.; Carroll, Jeffery A.
A study was designed to determine the effects of feeding dehydrated citrus pulp (DCP) on feedlot performance of newly-received English × Continental heifers. Heifers (n=180) were sourced in two loads (188.7 ±18.0 kg and 225.2 ± 22.2 kg, respectively) from commercial auction barns and placed on trial at the Texas Tech University Beef Center in New Deal, Texas. A completely randomized block design was utilized with BW nested within arrival load and blocked by BW. Three dietary treatments were fed (36 pens; 5 heifers/pen; 12 blocks; 3 pens/block; 12 pens/treatment). Treatment diets were formulated to contain: 1) 0%; 2) 10%; or 3) 20% DCP on a DM basis. Diets containing DCP were formulated to be exchanged with steam flaked corn on a 1:1 basis. Cattle were fed a 63, 73, and 83% concentrate diet from d 0 to 28, d 28 to 42, and d 42 to 56, respectively. Over the entire 56-d trial period, as the amount of dietary DCP increased DMI decreased (P = 0.02; 6.70, 6.13, and 5.96 kg, for 0, 10, and 20% DCP, respectively), ADG decreased (P < 0.0001; 1.88, 1.27, and 1.00, respectively), and G: F decreased (P = 0.02; 0.225, 0.210, 0.191, respectively). From d 0 to d 28 there was no difference in the observed, minus the expected NEg of the diet (P = 0.73), from d 28 to d 42 there was a linear increase in NEg with an increase in the percentage of DCP (P=0.003), and from d 42 to d 56 there was a linear increase in NEg favoring CON cattle over DCP cattle (P = 0.006). At the conclusion of the trial a subset of heifers (n = 24; 218.3 ± 2.4 kg) were utilized to evaluate the physiological and acute phase responses (APR) to an endotoxin (lipopolysaccharide; LPS) challenge. On d 63, heifers were fitted with jugular catheters and moved into individual stalls. On d 64, heifers were challenged i.v. with LPS (0.5 µg/kg BW), and blood samples were collected every 0.5 h from -2 to 8 and again at 24 h relative to LPS challenge (0h). Sickness behavior scores (SBS) were assigned following collection of each blood sample. Serum was analyzed for cortisol, interleukin-6 (IL-6), interferon-γ (IFN-γ), and tumor necrosis factor-α (TNF-α) concentrations as well as serum glucose, blood urea nitrogen (BUN), and non-esterified fatty acid (NEFA) concentrations. Post-LPS SBS increased (P < 0.01) and were greater in 10% DCP than 20% DCP and CON. Heifer BW was measured at cannulation, and 24 and 72-h ) post-LPS. BUN levels showed a treatment effect pre-LPS favoring CON cattle (P < 0.01). Post-LPS glucose, NEFA, and BUN concentrations were greater in CON cattle (P < 0.01) cortisol concentrations were greatest in 10% DCP heifers than CON and 20% DCP treatments ( P < 0.01). IFN-γ, TNF-α, and IL-6 increased post-LPS (P < 0.01) and were greater in 20% DCP over 10% DCP and CON treatments ( P < 0.01). These data indicate that dietary DCP can modulate both the physiological and APR of newly-received heifers to an endotoxin challenge, and it effects feedlot performance variables.
Determining the prevalence and antimicrobial susceptibility of salmonella serovars isolated from U.S. retail ground pork
(2014-12) Broadway, Paul R.; Brooks, J. Chance; Miller, Markus F.; Loneragan, Guy H.; Carroll, Jeffery A.; Wittum, Thomas E.
Salmonella is a foodborne pathogen that can be associated with meat products and can cause disease or death in humans. The first objective of this study was to determine the overall prevalence of Salmonella in ground pork in stores in the United States over three seasons and four regions. Both case-ready and store-ground packages were obtained throughout the study. The package types collected were overwrap, chub, modified atmostphere packaging (MAP) and other. Because these package types represent different production systems and are subject to different microbiological government regulation and testing methodologies, both USDA-FSIS and FDA Salmonella isolation protocols were used. Another objective of the study was to determine the serotypes and antimicrobial resistance profiles of the isolates found. Ground pork aliquots were subjected to real-time PCR isolation. Recovered isolates were then serotyped and minimum inhibitory concentration analysis (MIC) to 15 antimicrobial compounds was determined using micro-broth dilution in accordance with the national antimicrobial resistance monitoring system (NARMS). The overall prevalence of Salmonella in ground pork from the 865 samples collected was 1.39%. Prevalence was not affected by package type (P = 0.29) or grind location (case-ready vs. store-ground; P = 0.17). Season affected Salmonella prevalence (P = 0.05) with most isolates found during the fall season, and there was a tendency for region to affect Salmonella prevalence (P = 0.07). The USDA Salmonella isolation method was more effective at recovering isolates from packages (P = 0.01) in comparison to the FDA methodology and yielded a Kappa statistic of 0.26 as a measure of agreement. The serotypes isolated included: Infantis, 4,5,12:i:-, Brandenburg, Typhimurium var 5-, Seftenberg, and Johannesburg with only 2 packages containing multiple serotypes. There were no isolates resistant to antibiotics used to treat Salmonella infections including extended spectrum cephalosporins or flouroquinolones. Overall, the prevalence of retail ground pork in the U.S. retail market is very low.
Effect of citrus byproducts on survival of O157:H7 and non-O157 escherichia coli serogroups within in vitro bovine ruminal microbial fermentations
(2013) Duoss-Jennings, Heather A.; Schmidt, Ty B.; Callaway, Todd R.; Carroll, Jeffery A.; Martin, James M.; Shields-Menard, Sara A.; Broadway, Paul R. (TTU); Donaldson, Janet R.
Citrus byproducts (CBPs) are utilized as a low cost nutritional supplement to the diets of cattle and have been suggested to inhibit the growth of both Escherichia coli O157:H7 and Salmonella. The objective of this study was to examine the effects in vitro that varying concentrations of CBP in the powdered or pelleted variety have on the survival of Shiga-toxin Escherichia coli (STEC) serotypes O26:H11, O103:H8, O111:H8, O145:H28, and O157:H7 in bovine ruminal microorganism media. The O26:H11, O111:H8, O145:H28, and O157:H7 serotypes did not exhibit a change in populations in media supplemented with CBP with either variety. The O103:H8 serotype displayed a general trend for an approximate 1 log 10 reduction in 5% powdered CBP and 20% pelleted CBP over 6 h. There was a trend for reductions in populations of a variant form of O157:H7 mutated in the stx1 and stx2 genes in higher concentrations of CBP. These results suggest that variations exist in the survival of these serotypes of STEC within mixed ruminal microorganism fluid media when supplemented with CBP. Further research is needed to determine why CBPs affect STEC serotypes differently. © 2013 Heather A. Duoss-Jennings et al.
Effect of single versus group housing from the first week of life on the performance, immune responses, and well-being of Holstein calves.
(2012-08) Cobb, Clayton; Ballou, Michael A.; Carroll, Jeffery A.; Reilly, Brian D.
Recent worldwide concern for animal well-being has raised many questions considering animal housing. Currently, many believe that gregarious animals should be housed in groups in order to maintain natural behavior. Unfortunately, there is not a consensus within the scientific community with regard to the definition of well-being, or even how to precisely and accurately measure animal well-being. Thus far, some criticize that “legislation driven” research is not properly conducted. Therefore, researchers typically collect physiological, immunological, and endocrine measurements that correlate with symptoms of subjective characteristics. By evaluating immune response measurements, blood metabolites, protein activity, and intake; we can better ascertain proper animal welfare, enhance animal well-being, and begin to make changes that provide better living conditions. In Experiment I, calves were enrolled and housed in outdoor individual and group pens (n = 3) within the first week of life. After a short acclimation period, whole blood samples were collected to measure innate immune responses and blood metabolites that may distinguish stressed or diseased animals from those possibly experiencing better well-being. Milk replacer and calf starter intakes, gains, disposition, and fecal scores were recorded daily. Behavioral data were also collected in order to determine social development differences between housing scenarios that could result in heightened stress, fear, disease transmission, and risk of future dysfunctional behavior. Frequency of observations and samplings were amplified prior and during weaning to more precisely evaluate physiological and behavioral changes as a result of weaning stress. Once weaned and of appropriate age and weight, calves were randomly commingled outdoor into groups (n = 5) to distinguish further effects of post-wean commingling that occurs in production. In Experiment II, calves were enrolled and housed in indoor individual and group pens (n = 2 and 3) within the first week of life. The intent of this experiment was to replicate group housing of outdoor calves, but in a more homogenous indoor environment with closer animal interactions to determine if the effects were similar as observed in outdoor situations or more affected by external stimuli such as ventilation, disease transmission, and enhanced perception of sound and sight due to close proximity of neighboring pens. Replication of experiments may aid in distinguishing if group housing has an effect on calf well-being in two separate and common housing methods. Evaluation of data from both scenarios will lead to more understanding of group housing by considering the performance, immunological, and behavioral responses to environmental and interactive stimuli. When housed outdoor, group-housed calves experienced greater dry matter intake resulting in increased average daily gain. Incidence of cross-sucking was heightened in group-housed calves, consequently amplifying horizontal disease transmission and stimulating activation of neutrophils of the innate immune system compared to individually housed calves. As interaction with pen-mates became evident to researchers, grouped calves became more evasive to human contact and showed more behavior characteristic of fear when in a novel environment compared to individually housed calves. In order to discourage intersucking or milk stealing, calves were swayed to suckle a dry nipple. Therefore, more labor time was spent with group-housed calves to assure proper intake of nutrients. When later commingled, outdoor group-housed calves had enhanced gains. As in outdoor group housing, competition within indoor group pens resulted in increased post-wean intake, but possibly more activity and physical interaction did not allow for increased gain in these groups. Common inadequate ventilation and high humidity noted in indoor housing scenarios could result in narrow environmental variation among treatments. Horizontal transmission of pathogens was not limited to pens because calves resorted to reaching around, through, or over wall separations to attain interaction. As this was the case, there was little difference in innate immune responses or blood metabolites as a possible result of calf-to-calf interactions and/or lack of treatment effect. Indoor calves were in much closer proximity with each other, allowing for visual, audible, and limited physical interaction. Close proximity of pens also allowed social interaction by all animals in the barn, creating less varied behavioral differences than seen in outdoor calves. The dilution effect due to homogeneity of the environment and stimuli led to equal reaction of all indoor calves in the commingling period. In turn, group housing can increase post-wean intake, but social interaction, environment, and disease transmission control all affect the responses of performance, the innate immune system, and proper behavioral development.
Effects of dietary source and level of energy on the immune competence and response to an infectious Bovine Rhinotracheitis Virus (IBRV) challenge in cattle
(2010-05) Schwertner, Luke; Ballou, Michael A.; Carroll, Jeffery A.; Galyean, Michael L.
[not available]
Evaluation of yeast, nonsteroidal anti-inflammatory, and metaphylaxis products in feedlot cattle: Mitigation of bovine respiratory disease and feedlot performance
(2018-08) Word, Alyssa Brook; Ballou, Michael A.; Carroll, Jeffery A.; Burdick Sanchez, Nicole; Neary, Joseph M.; Holland, Ben
Bovine respiratory disease (BRD) is the leading cause of morbidity and mortality in United States feedlots. Economic consequences associated with BRD include treatment costs, potential performance reduction, and increased labor requirements. Feedlot BRD is historically difficult to study as it is a disease of multi-factorial nature with low predictability. Therefore, improved means of BRD prevention and treatment as well as improved methods of studying BRD in newly received feedlot cattle continue to be important factors in reducing this economic burden and improving beef cattle health. The objective of the first study was to evaluate the feeding of a combination Saccharomyces cerevisiae live yeast and S. cerevisiae yeast cell wall supplement compared to a negative control in beef heifers administered a BRD challenge. Thirty-two heifers were challenged intra-nasally with 1 × 108 plaque forming units (PFU) of Bovine Herpesvirus-1 (BHV-1) followed by of 3.0 × 107 colony forming units (CFU) of Mannheimia haemolytica 72 h later. Blood was collected for 72 h following the M. haemolytica challenge. Heifers fed yeast had similar vaginal temperature to control heifers and serum concentrations of cortisol, leukocyte, haptoglobin, and NEFA were unaffected by the inclusion of dietary yeast (P ≥ 0.13). However, concentrations of serum glucose were greater (P = 0.01) in cattle fed yeast when while serum concentrations of urea N were decreased (P = 0.03) when cattle were fed yeast. While feeding the combination live yeast and yeast cell wall supplement did not affect the response of the immune variables measured to a BRD challenge, some aspects of the metabolic response to a live BRD challenge were improved when yeast was included in the diet. The objective of the second study was to evaluate the effects of inclusion of the same combination live yeast and yeast cell wall product in the diet of feedlot heifers on growth performance, carcass characteristics, and health during the feeding period. A generalized randomized complete block design with 2 time blocks, 2 treatments, and 8 pen replications per treatment (70 heifers/pen) was used in heifers fed for 166 d. Live growth performance measured by final BW, ADG, DMI, and G:F were not affected by the dietary inclusion of yeast (P ≥ 0.40). Similarly, carcass characteristics including HCW, dressing percentage, and distribution of quality and yield grades were unaffected by the dietary inclusion of yeast (P ≥ 0.28). Morbidity and mortality were also unaffected by treatment (P ≥ 0.14). Inclusion of the live yeast and yeast cell wall product did not affect the feedlot performance or overall health of heifers experiencing low morbidity and mortality during the feeding period. The third study was conducted to evaluate the effects of altered timing of administration of transdermal flunixin meglumine (FM) on the immune and metabolic response of beef heifers administered a BRD challenge. All heifers were challenged intra-nasally with 1 × 108 PFU of BHV-1 followed by 1.18 × 106 CFU of M. haemolytica 72 h later. Four treatments were used where transdermal FM was applied at the time of arrival, at the time of BHV-1 challenge, at the time of M. haemolytica challenge, or not at all (8 heifers/treatment). Vaginal temperature was similar when transdermal FM was applied at arrival or not at all, but reduced when transdermal FM was applied at the time of BHV-1 or M. haemolytica challenge (P = 0.04). Immune and metabolic variables measured including leukocyte counts, pro-inflammatory cytokines, NEFA, urea N, and haptoglobin were unaffected by administration of transdermal FM for 72 h following the BRD challenge (P ≥ 0.16). However, neutrophil oxidative burst capacity and L-selectin expression decreased following administration of transdermal FM (P ≤ 0.09). Application of transdermal FM was therefore effective for the reduction of pyrexia when applied during the BHV-1 or M. haemolytica challenge without affecting the immune or metabolic response to the BRD challenge, with the exception of a slight reduction in neutrophil functionality that could result in reduced neutrophil associated inflammation in cattle receiving transdermal FM. The fourth study was conducted to evaluate a multi-site field experimental design used to study relative efficacies of metaphylaxis products in feedlot cattle at high-risk for the development of BRD. Four locations enrolled 5,222 steers, bulls, and heifers in 3 treatments: gamithromycin (Zactran, 6 mg/kg BW), tildipirosin (Zuprevo, 4 mg/kg BW), or tulathromycin (Draxxin, 2.5 mg/kg BW) administered on-arrival. Treatments were mixed within pens and data were analyzed as a nested design such pen was nested within feedlot location. No treatment × feedlot interactions were detected for any variable analyzed (P ≥ 0.11). Morbidity from BRD was reduced in cattle receiving tulathromycin compared to tildipirosin, and tildipirosin compared to gamithromycin. Mortality was reduced in tulathromycin and similar between tildipirosin and gamithromycin. Similarly, HCW was heaviest when cattle received tulathromycin and similar between tildipirosin and gamithromycin. Advantages of the study design included the spread of labor and infrastructure strain associated with BRD outbreaks in large groups of cattle over multiple feeding locations and over time, theoretically equal exposure of animals in all treatments to pathogen exposure or any other random variation associated with pen, and the increased probability of consistent blinding of feedlot personnel to treatment. Disadvantages included the difficulty of measuring treatment feed intakes, limitation to studying means of prevention that are applied directly to the animal, and difficulty in enforcing different post-metaphylaxis intervals for each treatment. These data support the continued need for BRD research in the feedlot setting. While the inclusion of S. cerevisiae in the diet may affect some aspects of the metabolic response when cattle are immunologically challenged, these data do not support improvement to feedlot performance when cattle are at low-risk of BRD development. Furthermore, these data provide some evidence that application of transdermal FM during a BRD event could be an effective means of pyrexia reduction without affecting the immunological and metabolic responses to a BRD challenge, and with minimal reduction in leukocyte functionality. Finally, a multi-site field model where animals within treatment are mixed in a pen could provide a viable alternative to the randomized complete block design for the field study of BRD where large numbers of cattle at high-risk for BRD development are enrolled at one time and where infrastructure or labor limitations exist.
Exploring the links between stress and innate immune responses in cattle
(2010-12) Hulbert, Lindsey E.; Ballou, Michael A.; Carroll, Jeffery A.; Randel, Ronald D.; Welsh, Thomas H.; Galyean, Michael L.
Cattle morbidity and mortality are observed more frequently during potential stressful situations, such as weaning, transportation, and commingling. The objectives of this dissertation were to identify intrinsic factors, such as sex-classification and temperament and extrinsic factors such as transportation, feeding strategies and weaning that might influence the stress and innate immune responses of cattle. A sexually dimorphic immune response to endotoxin or corticotropin-releasing hormone (CRH) was observed among Brahman heifers and bull calves. Heifers displayed less sickness behaviors but had greater rectal temperature and circulating tumor-necrosis-factor alpha (TNF-α) response to an in vivo endotoxin challenge than bulls. Heifers also had less of a circulating corticoid response than bulls after CRH and had an acute increase in circulating cytokines that was greater than bulls. Brahman bulls classified as temperamental had less neutrophil activity after transportation than bulls classified as calm. Weaning is a potentially stressful event for calves.. Many innate immune responses in Holstein calves including neutrophilia and decreased phagocytic and oxidative burst capacities were suppressed transiently following weaning. Early weaning calves at 24 d of age rather than at 45 d of age also suppressed neutrophil L-selectin expression. Furthermore, early weaning lightweight calves also suppressed the secretion of TNF-α from whole blood cultures stimulated with LPS. Switching Holstein calves from twice daily to once a daily feeding during the 4th week of life was a mild stressor. There was only a tendency for neutrophilia among the once-fed calves. No other aspects of innate immune responses were acutely suppressed by feeding frequency. These studies indicate that the stress effect of stress on immune responses of cattle is complex. Sex classification, age, and temperament of cattle influence how an animal responds to stress and subsequently, how stress will impact the innate immune system. These studies all indicate that stress can cause an initial suppression of the immune system, but in several instances, the innate immune system had compensatory response, where increased activity after stress is observed.
Immune responses and performance are influenced by respiratory vaccine antigen type and stress in beef calves
(2020) Hudson, Rachel E.; Tomczak, Dexter J.; Kaufman, Emily L.; Adams, Ashlee M.; Carroll, Jeffery A.; Broadway, Paul R.; Ballou, Michael A. (TTU); Richeson, John T.
The study objective was to determine if a combined weaning and transportation stress model affected performance, antibody, endocrine, or hematological responses to modified-live virus (MLV) or killed virus (KV) respiratory vaccination in beef steers. In total, 48 calves (Day 0 BW = 226 ± 6.2 kg) from a single origin were used in a 2 × 2 factorial to evaluate main effects of stress model, vaccine type, and their interaction, resulting in four treatments (n = 12/treatment) including nonstress control (C) with KV (CKV), C with MLV (CMLV), stress model implementation (S) with KV (SKV), and S with MLV (SMLV). The C calves were weaned at the origin ranch on Day −37 and transported 472 km to the study site on Day −21 to allow acclimation. The S calves were weaned on Day −3, transported 460 km to a research facility on Day −2, held overnight, and transported 164 km to the study site on Day −1 to mimic the beef cattle marketing process. Vaccines were administered on Day 0 and KV was revaccinated on Day 14. The animal was the experimental unit and dependent variables were analyzed using PROC MIXED with repeated measures (day). A stress model effect (p = 0.01) existed for DMI from Day 0 to Day 7 with greater DMI for C (6.19 vs. 4.64 kg/day) when compared to S. The MLV groups had reduced (p = 0.05) ADG from Day 0 to Day 56, compared to KV. There was a vaccine type × day (p < 0.01) interaction with increased (p ≤ 0.01) PI3V- and IBRVspecific antibody titers for KV on Day 21; conversely, MLV had increased (p ≤ 0.01) BVDV titers on Days 14, 28, 35, 42, 49, and 56. Increased (p ≤ 0.05) BRSV titers were observed in a stress model × day (p < 0.01) interaction for S on Days 21, 28, 36, and 42; however, C exceeded S in BVDV-specific antibody concentration on Days 21, 28, and 49. A day effect (p < 0.01) was observed for serum haptoglobin with the greatest (p < 0.01) concentration on Day 3. Serum cortisol concentration was greater (p ≤ 0.04) for C vs. S on Days −2, 0, 1, 3, and 5. Total leukocytes were decreased for C vs. S on Days 0, 1, 3, 5, 7, 14, and 21 (p ≤ 0.02). A reduction (p ≤ 0.04) in total leukocytes was observed for MLV on Days 5, 7, and 14 vs. KV. Neutrophils and neutrophil:lymphocyte were markedly increased (p ≤ 0.01) for S on Day −2, whereas neutrophils were decreased (p ≤ 0.01) on Days 1 and 21 for S. Monocytes were decreased on Days 1, 5 and 7 for MLV (p ≤ 0.04) and Days −2 to 14 for S (p ≤ 0.03). Eosinophils were reduced (p = 0.007) for S vs. C on Day −2, yet a distinct rebound response (p = 0.03) was noted for S on Day 0. The results indicate that S and MLV vaccination more profoundly induced immunomodulation in beef calves.
Immunological effects of pre-weaning plane of nutrition and yeast fermentation products on respiratory disease in dairy calves
(2016-11-21) Sharon, Kate; Ballou, Michael A.; Carroll, Jeffery A.; Trojan, Sara J.; Neary, Joseph M.; Burdick Sanchez, Nicole
Respiratory disease continues to be responsible for the majority of morbidity and mortality in cattle. Explanations for this are many; however some influences may include early-life nutrition, stress and other immune-compromising factors. In addition, routine antibiotic usage is being increasingly scrutinized. For this reason, both improved management practices and alternative therapies are significant. Early-life nutrition can influence productivity later in life; therefore, potential improvement of disease resistance during the pre-weaning period may be possible. Natural immune-enhancing products are also proving to be beneficial. Yeast products, specifically Saccharomyces cerevisiae and its derivatives have been shown to enhance immune variables. Bovine respiratory disease complex (BRDC) includes viral and bacterial pathogens; two specific pathogens include BHV-1 and M. haemolytica. A sensible disease model includes both a viral and bacterial component to emulate a BRDC infection. Limited data are available in combined viral-bacterial challenges; therefore, multiple doses of M. haemolytica were utilized. This challenge model aimed to induce morbidity but not induce mortality. In the first study, the objectives were to determine if pre-weaning plane of milk replacer nutrition influenced health and performance of high-risk Holstein bull calves. Calves were fed either a high (HPN; 830g DM/d of milk replacer during the first 10 d and 1080g from 11d until weaning) or a low plane of milk replacer nutrition (LPN; 445g DM/d of milk replacer until weaning) through weaning. Calves fed the HPN performed better than LPN calves in the first 25 d both in ADG and G:F as well as having greater final body weights. However, calves on the HPN had greater incidence of bloat and scouring but there was no difference in antibiotic treatment frequency. The results of this study suggest risk for gastrointestinal issues is greater in HPN calves, but performance is improved. In the second study, the effect of plane of milk replacer nutrition and M. haemolytica (MH) dose were studied in Holstein calves during a viral-bacterial respiratory challenge. Calves were challenged with 1.5 x 108 PFU/mL/nostril of bovine herpesvirus-1 (BHV-1) and with either 106, 107, or 108 CFU of MH 3 d later. Four LPN calves either died or were euthanized soon after the 144 h observation period, while all HPN calves survived the entire observation period. Calves previously fed a LPN had greater plasma haptoglobin and neutrophil concentrations as well as greater rectal temperature during the BHV-1 challenge. Haptoglobin and neutrophil concentrations as well as inflammatory cytokines were greatest in calves receiving the highest MH dose at various time points following the MH challenge. The BHV-1 neutralizing antibody titer dilution concentrations were similar between treatments immediately before the BHV-1 challenge; however, 9 d after the challenge the HPN calves had greater antibody titers compared to LPN calves. These data demonstrate that greater doses of MH increase the acute inflammatory response and prolong inflammation and that calves previously fed a LPN responded more severely to the combined viral-bacterial respiratory challenge. The second study also investigated metabolic responses to a combined viral-bacterial respiratory challenge. Calves previously fed a HPN were heavier than LPN calves; however no difference in ADG or starter intake per kg BW0.75. Serum glucose concentrations were greater throughout the challenge in HPN calves. Following the MH challenge, LPN calves had numerically greater serum NEFA and serum urea nitrogen concentrations. Further, calves receiving 108 MH had the greatest NEFA concentrations. Calves fed a LPN during pre-weaning appeared respond more severely by evidence of reduced glucose concentrations and increased NEFA concentrations suggesting intensified immune cell energy requirements and a more severe infection. Calves fed a LPN during pre-weaning may experience greater disease during a respiratory challenge. In the third study, the effects of a Saccharomyces cerevisiae fermentation product, NutriTek (Diamond V, Cedar Rapids, IA), on leukocyte functionality and ex vivo cytokine production during a dexamethasone (DEX) challenge was studied. Holstein steers were supplemented with 0, 20, 40, or 60 g/head/d of NutriTek. Dexamethasone was administered via jugular catheter at 0.1 mg/kg BW at 0, 6, and 12 h. Total leukocytes counts and neutrophil concentrations increased with NutriTek dose. NutriTek did not affect neutrophil L-selectin concentration. Phagocytosis and oxidative burst function recovered better in neutrophils and monocytes with increasing NutriTek dose. Overall, NutriTek supplementation influenced peripheral neutrophil concentrations and may have increased recovery of neutrophil and monocyte function. In the fourth study the effects of a Saccharomyces cerevisiae fermentation product, NutriTek (Diamond V, Cedar Rapids, IA), fed to Holstein steers during a viral-bacterial respiratory challenge was investigated. Holstein steers were supplemented with 0, 20, 40, or 60 g/head/d of NutriTek. All calves were challenged with 1.5x108 PFU/mL/nostril of bovine herpesvirus-1 and with 106 CFU of M. haemolytica (MH) intratracheally 3 d later. NutriTek did not affect rectal temperature or total leukocytes counts and peripheral neutrophils. However, there was evidence for acute effects of NutriTek as lymphocyte concentrations were different among treatments. Inflammatory markers, including serum haptoglobin and ex vivo TNF-α production were not affected. These results indicate that NutriTek may influence some acute leukocyte responses during a viral-bacterial respiratory challenge, but did not have strong influences on measures of inflammation or disease. Overall, these data support there are differences in inflammatory and metabolic responses in calves fed different planes of nutrition during respiratory disease. Calves fed greater planes of nutrition may benefit during disease. Further, Saccharomyces cerevisiae fermentation product, NutriTek (Diamond V, Cedar Rapids, IA) may influence some leukocyte populations and function. However, these data cannot conclude significant immunological effects from this product.
Immunological effects of yeast products on pre-weaned dairy calves
(2016-05) Harris, Tyler; Ballou, Michael A.; Jackson, Samuel P.; Carroll, Jeffery A.; Trojan, Sara J.; Kottapalli, Kameswara Rao
Enteric disease continues to account for a large proportion of morbidity and mortality among dairy calves in the first few weeks of life. After the first 48 hours of life until weaning, approximately 10% of calves die. There are many enteric pathogens that cause severe local and systemic disease with high risk of mortality. In the past, metaphylactic use of antibiotics was widely used in the dairy industry, but lately there has been increased concern in the metaphylactic use of antibiotics. Because of this, there is interest in finding alternatives to antibiotic use that show similar efficacy as antibiotics in reducing disease. Yeast products, specifically those derived from Saccharomyces cerevisiae, have been shown to improve performance and health characteristics in calves. The three Saccharomyces cerevisiae derived products of interest in this research are: Yeast cell wall, yeast culture, and live yeast supplements. In the first study, the effects of yeast culture were studied in Holstein dairy calves infected by Citrobacter freundii. These bacteria are opportunistic pathogens that are common in neonatal animals. Yeast culture was supplemented to calves in the milk (SmartCareTM; SC) and calf starter (XPCTM; XPC). Treatments in the study were: CON: milk replacer and calf starter with no added yeast fermentation products; SC: milk replacer with 1 g SC/calf/d and base calf starter; and SC+XPC: milk replacer with 1 g SC/calf/d and calf starter with 0.5% XPC. Calves in the SC treatment had less signs of infection, indicated by reduced neutrophil to lymphocyte ratios and lowered fecal scores after the Citrobacter freundii challenge. The SC+XPC calves had increased calf starter consumption and ADG after the Citrobacter freundii challenge, and also had reduced neutrophil to lymphocyte ratios and fecal scores after the Citrobacter freundii challenge. The results of the study indicate that calves supplemented with yeast culture had improved performance, health, and risk of scours during neonatal life. In the second study, the effects of yeast culture were studied in Holstein dairy calves infected by Salmonella enterica serotype Typhimurium. Salmonella enterica is one of the more common enteric pathogens found on dairies in the United States, and is the cause of many calf deaths. Yeast culture was supplemented to calves in the milk (SmartCareTM; SC) and calf starter (XPCTM; XPC). Treatments in the study were: CON: milk replacer and calf starter with no added yeast fermentation products; SC: milk replacer with 1 g SC/calf/d and base calf starter; and SC+XPC: milk replacer with 1 g SC/calf/d and calf starter with 0.5% XPC. The SC treatment calves had greater calf starter consumption and reduced fecal shedding of Salmonella enterica. The SC+XPC treatment calves had improved calf starter consumption, greater ADG, reduced neutrophil to lymphocyte ratio, reduced hematocrit, less hemoglobin concentration, and reduced Salmonella enterica shedding after being challenged with Salmonella enterica. These results indicate that both SC and SC+XPC improved performance and enteric health, with the combination treatment having the greatest beneficial effects. In the third and final study, the effects of supplementing milk replacer with SafmannanTM (SM) and ActiSafTM (AS) on calf health and performance throughout the pre-weaned and immediate post-weaned periods were studied. Calves were randomly assigned to treatments that included; CON: milk replacer with no added supplements; SM: milk replacer with 5g SM/calf/d; SM + AS: milk replacer with 2g SM/calf/d and 3g AS/calf/d. The SM calves had reduced leukocyte and neutrophil counts on d 10 and 28 of the study when compared to Con calves, indicating limited pathogenic bacterial exposure. The SM calves had the greatest expression of neutrophil L-selectin an also had greater percentages of neutrophils phagocytizing and producing an oxidative burst on d 28, indicating “priming” of the immune system. The SM + AS calves had increased calf starter consumption in the first weeks of the study. The least number of calves scoured throughout the study in the SM + AS treatment group. Like the SM calves, total leukocyte counts and neutrophil counts were also reduced in the SM + AS calves on d 10, when compared to Con calves. These data suggest that both yeast supplementation strategies may aid in the growth and health of pre-weaned, Holstein calves, with the SM + AS treatment having a more profound positive effect on performance and gastrointestinal health, the SM treatment having a more positive effect on neutrophil activity, and both yeast products having a positive effect on circulating white blood cell numbers.
Improvements, challenges, and validation of enumeration of Escherichia coli O157 and sampling methods for Escherichia coli O157 and Salmonella in feedlot cattle
(Texas Tech University, 2006-12) Stephens, Tyler; Brashears, Mindy M.; Alvarado, Christine Z.; Loneragan, Guy H.; Carroll, Jeffery A.; Pond, Kevin R.; Warner, Ronald D.
Escherichia coli O157 and Salmonella have been targeted as food-borne pathogens of concern to the beef industry. Enumeration of and proper detection protocols for E. coli O157 and Salmonella has become an important part of pre-harvest surveillance and testing of intervention strategies. The objectives of this research were: (1) to improve and validate a Most Probable Number (MPN) / Immunomagnetic Separation (IMS) method to enumerate E. coli O157 in fecal samples from feedlot cattle; and (2) to determine the distribution of E. coli O157 and Salmonella on cattle hides (back, flank, hock, neck, perineum, and ventrum), the oral cavity, rectal-anal junction, and feces of feedlot cattle. Known quantities of E. coli O157:H7 were inoculated into feces and populations were determined by direct plating and compared to a MPN/IMS method. The MPN/IMS methodology compared to direct plating was tested in five experiments with varying E. coli O157 concentrations and it was found that there were differences (P < 0.01) between the two methodologies with negligible biological importance due to a low difference between least squares means (LS-means) (0.29 ± 0.01). The overall correlation coefficient was high (r = 0.93) which indicated that the MPN/IMS method was precise when compared to the direct plating method. Nine samples were obtained from feedlot cattle from the above mentioned locations (objective 2) and subjected to E. coli O157 and Salmonella detection protocols. Several measurements were taken: (1) prevalence of both pathogens at each location; (2) odds ratios comparing the fecal grab samples to all other locations; and (3) odds ratios comparing the perineum hide swab samples to all other hide swab samples. These data suggest that using multiple sample locations are useful when isolating these pathogens from feedlot cattle.
Infrared thermography or rectal temperature as qualification for targeted metaphylaxis in newly received beef steers and the effects on growth performance, complete blood count, and serum haptoglobin during a 42-day feedlot receiving period*
(2023) Smock, Taylor M. (TTU); Broadway, P. Rand; Burdick Sanchez, Nicole C.; Carroll, Jeffery A.; Hoffman, Ashley A. (TTU); Long, Nathan S. (TTU); Manahan, Jeff L. (TTU); McDaniel, Zach S. (TTU); Theurer, Miles E.; Wells, Jim E.; Hales, Kristin E. (TTU)
Objective: The objective was to evaluate rectal tem- perature and infrared thermography as qualification for targeted metaphylaxis, and effects on clinical health, growth performance, complete blood count, and serum haptoglobin in newly received beef steers during a 42-d feedlot receiving period. Materials and Methods: Crossbred beef steers (n = 240; arrival BW = 258 ± 22.5 kg) were used. Experimental treatments were arranged as a generalized complete block design: sterile saline (NCON); conventional metaphylaxis administered to all steers (CONV); targeted metaphylaxis administered to steers with rectal temperature ≥39.7°C (RECT); or targeted metaphylaxis administered to steers with ocular infrared temperature ≥39.7°C (EYE). Body weight and blood samples for quantification of complete blood count and serum haptoglobin were collected on d 0, 14, and 42 relative to metaphylaxis. Results and Discussion: Metaphylaxis was adminis- tered to 0% of NCON, 100% of CONV, 48.9% of RECT, and 48.6% of EYE steers (P < 0.01). Therapeutic bovine respiratory disease (BRD) treatment rate did not differ (P = 0.16), although overall BRD treatment rate was minimal. Metaphylaxis was 62.5% of total active antimicrobial compound administered to RECT and 32.1% of total ac- tive antimicrobial compound administered to EYE. Both methods of targeted metaphylaxis decreased percentage of animals administered antimicrobials relative to CONV (P < 0.01), but total milligrams of active drug compound administered was not different (P = 0.65). Body weight, DMI, DMI as percentage of BW, and G:F did not differ at any time point (P ≥ 0.07). A tendency (P = 0.06) was observed for ADG from d 0 to 14, where CONV was greatest, RECT and EYE were intermediate, and NCON was least. Day 0 to 42 ADG was greatest in CONV and RECT, least in NCON, and intermediate in EYE (P < 0.01). Platelet count tended (P = 0.10) to be greatest in NCON and RECT, followed by EYE and CONV. No further hematologic treatment differences were observed (P ≥ 0.22). Implications and Applications: Overall BRD morbidity was unexpectedly low in the present study. Both methods of targeted metaphylaxis decreased the propor- tion of animals administered antimicrobials relative to conventional metaphylaxis; however, total milligrams of active drug compound administered was not different. The ADG of steers administered targeted metaphylaxis based on rectal temperature did not differ from those ad- ministered conventional metaphylaxis. Use of targeted metaphylaxis with measures of body temperature may decrease the proportion of animals administered metaphylaxis while maintaining optimal health and growth perfor- mance outcomes.
Injecting Fusobacterium necrophorum into the peripheral circulation or hepatic portal vein of preruminant Holstein calves failed to induce liver abscesses*
(2024) Cox, Hannah E. (TTU); Menta, Paulo R. (TTU); Nagaraja, T. G.; Crossland, Whitney L. (TTU); Hales, Kristin E. (TTU); Henry, Darren D. (TTU); Strieder-Barboza, Clarissa (TTU); Broadway, Paul R.; Carroll, Jeffery A.; Ballou, Michael A. (TTU); Machado, Vinicius S. (TTU)
Objective: Our goal was to determine whether admin- istration of Fusobacterium necrophorum ssp. necrophorum into the jugular or portal vein will induce liver abscesses in preruminant calves. Materials and Methods: The study was performed as 2 experiments according to the inoculation site: jugu- lar vein or hepatic portal circulation. Experiment 1 was performed in 18 calves randomly assigned to receive intra- jugular infusion of saline (CONIV), or 107 (FUSOIV7), 109 (FUSOIV9), and 1011 (FUSOIV11) of F. necrophorum. In experiment 2, 20 calves were assigned to receive intrapor- tal infusion of saline or 106 (FUSOPV6), 108 (FUSOPV8), and 1010 (FUSOPV10) of F. necrophorum. Blood samples were collected on d 0, 1, 3, 5, 7, and 14 for hematology. Calves were slaughtered 14 d after inoculation and exam- ined for liver gross pathology. Results and Discussion: Neither model produced liver abscesses. However, in experiment 1, inoculation increased monocyte counts in FUSOIV11 calves versus CONIV, FUSOIV7, and FUSOIV9 on d 3 and 5 postchal- lenge. The neutrophil-to-lymphocyte ratio was greater for FUSOIV11 than CONIV and FUSOIV9 on d 7 postchallenge. In experiment 2, inoculation increased monocyte and neutrophils counts in the FUSOPV8 group compared with calves in other groups. Implications and Applications: Contrary to previ- ous reports, intraportal and intrajugular inoculation with F. necrophorum did not produce liver abscesses in preru- minant calves. Further research is necessary to explore alternative methodologies to use preruminant calves in experimental disease models for liver abscesses in cattle.
Modulation of the metabolic response using dexamethasone in beef steers vaccinated with a multivalent respiratory vaccine1
(2020) Sanchez, Nicole C.Burdick; Carroll, Jeffery A.; May, Nathan D.; Hughes, Heather D.; Roberts, Shelby L.; Broadway, Paul R.; Ballou, Michael A. (TTU); Richeson, John T.
Available energy plays a critical role in the initiation and maintenance of an immune response to a pathogen, a process that is further altered by activation of the stress system. This study was designed to determine the effect of an acute vs chronic stress model on the metabolic response to vaccination in naive beef steers. Steers (n = 32; 209 ± 8 kg) were blocked by body weight (BW) and randomly assigned to one of three treatments: 1) Chronic stress (CHR), 0.5 mg/kg BW dexamethasone (DEX) administered i.v. at 1000 h on day 3 to day 0; 2) Acute stress (ACU), 0.5 mg/kg BW DEX administered i.v. at 1000 h on day 0 only; or 3) Control (CON), no DEX. On day-4, steers were fitted with jugular vein catheters and moved into individual bleeding stalls in an environmentally-controlled facility. Blood samples were collected at-74,-50, and-26 h, at 0.5-h intervals from-4 to 6 h, and at 12, 24, 36, 48, and 72 h relative to vaccination with a combination vaccine (Pyramid 5 + Presponse SQ, Boehringer Ingelheim Animal Health USA, Duluth, GA) at 1200 h on day 0. Data were analyzed by the MIXED procedure of SAS specific for repeated measures. There was a treatment × time interaction (P < 0.001) for serum glucose concentrations. Specifically, glucose concentrations increased at-50 h in CHR steers and at 1200 h in ACU steers and remained elevated through 72 h postvaccination period in these two treatments compared to CON steers. The change in nonesterified fatty acid (NEFA) concentrations relative to baseline values was affected by treatment and time (P < 0.001) such that the change in NEFA was greater in CHR (0.06 ± 0.01 mmol/L), followed by CON (-0.01 ± 0.01 mmol/L) and ACU steers (-0.04 ± 0.01 mmol/L). There was a tendency (P = 0.08) for a treatment × time interaction for change in serum NEFA concentrations. Serum urea nitrogen (SUN) was affected by treatment and time (P < 0.001) such that SUN concentrations were greatest in CHR (12.0 ± 0.1 mg/dL) followed by ACU (10.4 ± 0.1 mg/dL) and CON steers (9.6 ± 0.1 mg/dL); however, the treatment × time interaction was not significant (P = 0.12). These data demonstrate that activation of the stress and immune axes using an acute or chronic stress model can increase energy mobilization prior to and following vaccination in naive steers, potentially affecting available energy needed to mount an adequate antibody response to vaccination.
Nutritional modulation of the immune system of beef cattle
(Texas Tech University, 2007-12) Reuter, Richard R.; Galyean, Michael L.; Carroll, Jeffery A.; Albin, Robert C.; Wester, David B.; Villalobos, Carlos
Experiments were conducted related to measuring and modulating the acute-phase immune response in beef cattle. In Exp. 1, bacterial lipopolysaccharide (LPS) was administered to 9 steers in doses of 0.5, 1.0, or 2.0 ¦Ìg/kg of body weight (BW) and the resulting serum cortisol concentration and rectal temperature (RT) were measured. Cortisol increased linearly (P = 0.01) with LPS dose, but RT increased independent of dose. In Exp. 2, 2.5 ¦Ìg/kg of BW of LPS was administered to 9 Angus steers. Serum concentrations of cortisol, interleukin (IL)-1¦Â, IL-6, tumor necrosis factor-¦Á (TNF¦Á), interferon-¦Ã (INF¦Ã), and serum amyloid-A (SAA), rectal temperature (RT), ruminal temperature, and respiration and perspiration rates were all increased following LPS challenge (P < 0.10). Rump perspiration rate, IL-4, and IL-2 were not changed (P > 0.24) by LPS challenge. In Exp. 3, a device was developed to automatically monitor RT in cattle. The autonomous device recorded RT at 1-min intervals in cattle in Exp 2. Rectal temperature measured with the device was related (P ¡Ü 0.02 ) to IL-6 and TNF¦Á concentration following LPS challenge. In Exp 4, two non-nutritive feed additives (Sucram, an artificial sweetener; Omni-GenAF, an immunomodulatory yeast product) were fed to newly received heifers for 44 d. Overall health and growth performance of the cattle were better than expected for heifers of the type and background used, and feed additives had no effect on growth, intake, or health. Nonetheless, the combination of Sucram and Omni-Gen AF decreased haptoglobin concentration on d 16 (P = 0.001). Deleterious effects of the additives on marbling score were evident (P = 0.05), and a long feeding period, relatively free of handling stress, mitigated negative effects of animal temperament on performance. In Exp 5, 70% and 30% concentrate diets were fed ad libitum to beef steers for 28 d (70AL and 30AL, respectively) to test the effects of energy source and energy intake on immune response. A third dietary treatment (70RES) consisted of the 70% fed in an amount restricted to equal the net energy for gain (NEg) intake of the 30AL treatment. Two days before an LPS challenge, 4 steers in each diet treatment were injected with tilmicosin phosphate (1 mL/30 kg of BW), and 4 steers were injected with an equal volume of saline. Steers were catheterized in the jugular vein and then challenged with 2.0 ¦Ìg LPS /kg of BW. Both energy source and energy intake affected the pro-inflammatory immune response; the 30% concentrate diet increased (P ¡Ü 0.05) TNF¦Á and INF¦Ã response to LPS compared with the 70% concentrate diet, and 70RES increased IL-6 (P = 0.003) response compared with 70AL. Tilmicosin accelerated the febrile response (P = 0.01) across all diets, and tilmicosin interacted with energy intake to increase pre-challenge levels of TNF¦Á, INF¦Ã, and IL-6, and SAA response to the challenge, in 70RES compared with 70AL (P ¡Ü 0.05). Nutrition and management practices have immunomodulatory effects in beef cattle. More precisely measuring the acute-phase response, and correlating responses to challenge models with clinical health performance in commercial environments will help researchers make more effective recommendations to cattle producers. Benefits to animals, producers, and the public can be realized when nutrition and management are effectively used to decrease morbidity in beef cattle.
Odors and pheromones: Influences of olfaction on behavior, physiology, and performance to reduce stress in pigs
(Texas Tech University, 2000-12) Krebs, Nadège; McGlone, John J.; Ballou, Michael A.; Carroll, Jeffery A.; Norman, Reid L.; Salazar, Ignacio
Reducing stress in pig husbandry has become a priority for economical and ethical reasons. The stress axis is anatomically linked to the olfactory system. Pigs have a very developed sense of olfaction. Reducing weaning or handling stress using the sense of olfaction would be a non-invasive and welfare-friendly technique. Exposing pigs at weaning individually to amyl acetate (banana smell, novel odor) or maternal pheromone did not reduce stress within the 2 h of the onset of weaning. Odors and pheromones increased lying behavior but the effects on cortisol concentration and immunology were limited compared to a control odor like water. An induced maternal odor was obtained by feeding sows an onion-flavored diet during lactation. Pigs were weaned onto onion-flavored diet. Onion-exposed pigs fought less at weaning but performance was not affected compared to pigs that had never been exposed to onion. Finishing pigs were trained to an olfactory/gustatory reward (maple syrup) at the finishing barn. When exposed to a novel environment (simulated pre-stun area) with the same reward present, handling time and pig welfare were improved compared to control pigs that had never been trained and were not exposed to maple syrup. Innate preferences to odors were assessed in domestic pigs (tested in a Y-maze) as a model to feral pigs' preferences to odors. Piglets were attracted to boar urine, fox urine, ChileGard™ (habanero pepper extract) and maple syrup and were repulsed by sour milk. Similar results were obtained in feral pigs.
Stress and allergic pulmonary inflammation
(2006-12) Hulbert, Lindsey E.; McGlone, John J.; Shome, Goutam P.; Carroll, Jeffery A.; Vizcarra, Jorge A.
The interactions between stress and allergic pulmonary inflammation are not well understood. Experiments were conducted utilizing the ovalbulmin (OVA) sensitization and aerosol challenge to induce allergic pulmonary inflammation in mice and stimulate the T helper (Th2) milieu immunity in female Balb/c mice. An Ovalbumin (OVA) sensitization and aerosol challenge model was utilized. The first study utilized an amphetamine withdrawal model as the stressor. There were no significant immune x stress interactions. An additive effect was observed for some Th2 cytokines and lung inflammation. The second study evaluated lipopolysaccahride challenge and forced swim test (FST), effects on mouse plasma corticocosterone levels at 20, 50, and 80 min after the start of exposure. FST treated mice, 50 minutes after exposure had the highest levels of corticosterone. Control mice also had elevated levels of corticosterone compared to literature baseline levels. The third study attempted to establish a time when full lung inflammation occurred. Sampling times included 0, 12, 24, 36 and 48 h after aerosol challenge. Mice harvested 0 to 24 h post allergen exposure had the most complete inflammatory response (not significant). The final study examined the effects of the FST on allergic pulmonary inflammation using the OVA induced allergy mouse model. Th2 cytokines in BAL fluid were elevated among allergic mice, the stressor reduced IL-5 and IL-6 concentrations in allergic mice, while the stressor alone (non-allergic) caused an increase in IL-4 and IL-10.
The influence of milk replacer plane of nutrition on the performance, innate immune responses and pathophysiological response to a sub-clinical Salmonella typhimurium
(2012-12) Hanson, Devin; Ballou, Michael A.; Trojan, Sara J.; Carroll, Jeffery A.
The objectives were to determine the influence of plane of nutrition during the pre- and post-weaning periods on performance and innate immune activity of Jersey calves. Forty-six (3 ± 1 d of age) calves were randomly assigned to 2 treatments. Treatments were a low (LP; n=23) and high Plane of nutrition (HP; n=23). Calves in LP treatment were fed 409 g/d DM of a 20% protein and 20% fat milk replacer; whereas calves in HP treatment were fed 610 and 735 g/d DM of a 28% protein and 25% fat milk replacer during the 1st wk and wk 2-6, respectively. Weaning was initiated on d 42 by removing the PM feeding and calves were completely weaned when they were consuming 600 g of a calf starter ration after d 49. Calves on the HP on nutrition were fed a calf starter with 20% CP and 18% ADF while the LP nutrition calves were fed a calf starter with 18% CP and 14.5% ADF. Calves were fed their respective calf starter diets through the entire study. Peripheral blood samples were collected on d 0, 7, 21, 28, 42 and 77 for biochemical analyses. Blood samples collected on d 7, 21, 42, and 77 were also analyzed for ex vivo innate immune responses. Twenty bull calves (HP n=9 and LP n=11) on d 77 were orally challenged with 1.5 x 107 colony forming units of Salmonella typhimurium (ATCC14028). Indwelling rectal thermometers collected a measurement every 5 min. and peripheral blood samples were collected daily at 0800 throughout the study and . plasma analytes and innate immune responses were determined. As expected, metabolizable energy intake, crude protein intake, and average daily gain were greater (P<0.001) for HP calves when compared to LP calves. There were treatment x time interactions (P<0.001) for plasma concentrations of glucose and urea nitrogen. Glucose concentrations were greater (P<0.01) on d 21, 28, 42 and tended to be greater (P<0.10) on d 77 among HP calves, when compared to LP calves. Urea nitrogen concentrations tended to be greater (P<0.10) on d 7 among HP calves, when compared to LP calves, but were less (P<0.01) than LP calves on d 42 and 77. Secretion of TNF-α from diluted whole blood when co-cultured with lipopolysaccharide was higher (P<0.05) among HP calves on d 7, when compared to LP calves. In contrast, neutrophil expression of L-selectin was greater (P<0.05) among LP calves on d 7, 21, and 42, when compared to HP calves. No treatment or treatment x time differences (P=0.798) were observed for neutrophil oxidative burst capacities during the study. Following the Salmonella typhi. challenge, the percentage of neutrophils producing an oxidative burst was greater (P<0.05) among HP calves from d 1 – 5 after the challenge. Similarly, the intensity of the oxidative burst tended to be greater (P<0.10) among HP calves on d 2 and 3 after the challenge. In addition, the secretion of tumor necrosis factor-α tended (P<0.10) to be greater on d 1 and was greater (P<0.05) on d 5 and 6 after the challenge among HP calves. Median ranks of haptoglobin concentrations were lower (P<0.05) among HP calves throughout the challenge; however, there was no difference (P=0.99) between LP and HP calves on rectal temperatures. These data indicate that LP calves have activated innate immune responses during the pre-weaning period, but HP calves have a more aggressive innate immune response to an oral Salmonella typhimurium challenge, which may improve resistance to disease.
The influence of plane of nutrition on development and health of gastrointestinal tract of calves
(2015-05) Liang, Yu; Ballou, Michael A.; Carroll, Jeffery A.; Trojan, Sara J.
The objectives of first study were to determine the digestibilities of nutrients as well as investigate the nitrogen retention of calves fed different planes of milk replacer nutrition during the first week of life. Twelve Jersey calves were blocked by BW at birth and randomly assigned to high plane of nutrition (HPN) or low plane of nutrition (LPN) treatments. The HPN calves were offered 20g DM/kg BW of a 28% CP and 20% fat milk replacer. The LPN calves were fed 14.5g DM/kg BW of a 20% CP and 20% fat milk replacer. All calves were given 3 L of pooled colostrum within 1 hour of birth after which they were assigned to treatments. Calves were given 1 day to adapt to treatment, accordingly, calves were 30 to 36 hours old at the start of data collection. The study was divided into two 72 hour periods. Total collection of feces occurred over each 72 hour period and total urine was collected for the last 24 hours of each period. Peripheral blood samples were collected at the beginning and end of each period and analyzed plasma glucose and urea nitrogen concentrations. Fecal scores were greater (P=0.004) for HPN calves during both periods; however, there was no difference (P≥0.253) in the dry matter percentage of feces. There were no differences (P≥0.239) between treatments in either digestible or metabolizable energy efficiencies, which averaged 92 and 83% for HPN and LPN, respectively. There was a treatment x period interaction (P=0.038) for the percentage of intake nitrogen retained, as HPN calves had greater percentage of intake nitrogen retained during period 1 (88.0 vs 78.7 ± 1.79; P=0.004), but was not different from calves fed the LPN during period 2 (85.3 vs 85.0 ± 1.79; P=0.904). Therefore these data indicate that neonatal calves have the capability to digest and absorb the additional nutrients with a higher plane of nutrition during the first week of postnatal life. The additional energy and amino nitrogen absorbed by calves fed the higher plane of nutrition were incorporated into lean tissue growth with a great efficiency. The objective of second study was to evaluate the effects of plane of milk replacer nutrition on the resistance to an opportunistic enteric challenge with Citrobacter freundii at 10 days of life. Twenty colostrum-fed Jersey calves were blocked by BW at birth and randomly assigned to either a high plane of nutrition (HPN) or low plane of nutrition (LPN) treatment. The LPN calves were fed 400 and 450 g DM/d of a 20% CP and 20% fat milk replacer during the 1st week and the remainder of the study, respectively. The HPN calves were fed 600 and 700 g DM/d of a 28% CP and 20% fat milk replacer during the 1st week and the remainder of the study, respectively. All calves were challenged orally with 1 x 108 colony forming units of a stationary phase culture of Citrobacter freundii at day 10. Fecal scores were recorded throughout the study and rectal temperatures were recorded daily immediately before and after the challenge. Fecal samples and plasma from peripheral blood samples were collected stored at -80oC at day 10, 12, 14, 16, 18, 20, 22, and 24 until further analysis. Fecal samples were analyzed for dry matter percentage and plasma was analyze for concentrations of urea nitrogen, glucose, and haptoglobin. All calves were harvested at day 24 and ileum tissue samples were analyzed for morphology. Water intakes were greater for the HPN calves before the enteric challenge (P≤0.062) and increased to a greater extent after the challenge (P≤0.021). Fecal scores were also greater among HPN calves (2.52 vs 2.04 ± 0.07; P=0.001); however, there was no difference in dry matter percentage of feces between treatments (19.9 vs 21.9 ± 1.34%; P=0.291). There was a difference in the dry matter percentage of feces scored as a fecal score 3 between the HPN and LPN calves (20.2 vs 16.3 ± 0.965%; P=0.006). Rectal temperatures were greater among the HPN calves (P=0.024). In addition, the HPN calves had numerically greater peak plasma haptoglobin concentrations after the challenge (511 vs 266 ± 108.0 μg/mL; P=0.118) and tended to have a greater total mucosal height of the distal ileum (921 vs 752 ± 59.1 μm; P=0.059). Therefore these data indicate that calves fed a HPN during the neonatal period have a mildly greater acute phase response to an opportunistic bacterial enteric infection and it may be associated with a greater mucosal surface area of the distal ileum. Furthermore, these data reiterate that fecal scores should not be the only measure of enteric health, especially when evaluating the effects of planes of nutrition.