Browsing by Author "Menta, P. R. (TTU)"

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Association of time to metritis diagnosis with circulating concentration of metabolites, minerals, and haptoglobin in Jersey cows
(2023) Menta, P. R. (TTU); Neves, R. C.; Machado, V. S. (TTU)
Our objective was to investigate the association of early metritis [EMET, diagnosed at <5 d in milk (DIM)] and late metritis (LMET, diagnosed at ≥5 DIM) with circulating concentrations of energy metabolites, minerals, and haptoglobin (Hp) throughout the first 14 d postpartum. A total of 379 purebred Jersey cows were enrolled in a prospective cohort study from a single herd in west Texas. Cows were examined for metritis using the Metricheck device (Simcro Ltd.) at 4, 7, and 10 DIM. Cows identified by farm employees as possible metritis cases were also evaluated for metritis. Blood samples were collected for analysis of concentrations of Ca, Mg, and glucose at DIM 1 through 5, 7, 10, and 14. Albumin, urea, fructosamine, free fatty acids (FFA), creatinine, and β-hydroxybutyrate (BHB) were analyzed at DIM 3, 5, 7, 10, and 14, and Hp at DIM 1 through 5 and 7. Data were analyzed using the MIXED and PHREG procedures of SAS (SAS Institute Inc.). A series of mixed general linear models accounting for repeated measures were fitted to the data. The independent variables metritis [no metritis (NMET), EMET, and LMET], DIM of analyte assessment, and parity were forced in all models. Multivariable Cox proportional hazard models were built to assess the risk of pregnancy and culling within 150 DIM. The overall metritis incidence was 26.9% (EMET = 49; LMET = 53; NMET = 277). Average concentrations of glucose, Mg, and urea were not associated with metritis. The associations of Ca, creatinine, BHB, and fructosamine with metritis were dependent on the DIM of analyte assessment. Cows categorized as EMET and LMET had, on average, lower albumin and fructosamine compared with NMET cows. Both EMET and LMET cows had, on average, greater BHB than NMET cows. A greater FFA concentration was only observed in cows diagnosed with EMET compared with NMET cows (EMET = 0.58, LMET = 0.52, NMET = 0.48 mmol/L). Additionally, circulating Hp concentration was greater for LMET and EMET compared with NMET cows, and EMET cows had greater Hp compared with LMET cows (EMET = 1.15; LMET = 1.00; NMET = 0.84). In conclusion, several blood biomarkers were temporally associated with early versus late metritis diagnosis in postpartum Jersey cows. No meaningful differences were observed in production, reproduction, or culling between EMET and LMET cows. These results suggest that cows with EMET undergo a more severe degree of inflammation and negative energy balance compared with NMET cows.
Effect of injectable trace mineral supplementation on peripheral polymorphonuclear leukocyte function, antioxidant enzymes, health, and performance in dairy cows in semi-arid conditions
(2022) Silva, T. H. (TTU); Guimaraes, I. (TTU); Menta, P. R. (TTU); Fernandes, L. (TTU); Paiva, D. (TTU); Ribeiro, T. L. (TTU); Celestino, M. L. (TTU); Netto, A. Saran; Ballou, M. A. (TTU); Machado, V. S. (TTU)
The objective of this study was to evaluate the effect of subcutaneous injections of 15 mg/mL Cu, 5 mg/mL Se, 60 mg/mL Zn, and 10 mg/mL Mn on health, performance, polymorphonuclear leukocyte (PMNL) function, circulating glutathione peroxidase (GPx) and superoxide dismutase (SOD) concentrations, and inflammation of dairy cows undergoing the transition period in high temperature-humidity index. A total of 923 multiparous cows from 2 commercial dairy farms were randomly allocated into 1 of 2 treatment groups as follows: control and injectable trace mineral supplementation (ITMS). Cows in the ITMS group received 7 mL of subcutaneous injections at dry-off (208 ± 3 d of gestation), 260 ± 3 d of gestation, and at 35 ± 3 d in milk (DIM). Data regarding health traits, reproductive performance, milk yield, and survivability were extracted from farm database software, and animals were followed-up until 300 DIM. For a subset of 142 cows from one herd, blood samples were collected at enrollment, and at 3 ± 1, 7 ± 1, 10 ± 1, and 35 ± 3 DIM to evaluate hematology, PMNL function, GPx and SOD concentrations, and circulating haptoglobin. Logistic regression was used to assess health and pregnancy per artificial insemination at first service. Cox proportional hazards models were used to evaluate hazard of pregnancy and culling. Mixed linear regression models accounting for repeated measures were used to assess all continuous variables collected over time. Parity, twinning, and previous gestation length were considered as potential confounders. Farm was included as a random effect. The ITMS cows tended to have lower incidence of metritis and stillbirth compared with control group. However, ITMS treatment did not influence the incidence of other diseases (e.g., mastitis, retained placenta), milk yield, reproductive performance, culling, and leukocyte count. Neutrophil-to-lymphocyte ratio, PMNL phagocytosis, and oxidative burst as well as intensity of the oxidative burst were greater for ITMS-treated cows in comparison to control cows. The ITMS cows had decreased expression of the adhesion molecule L-selectin on PMNL surface. The serum concentration of GPx and SOD were not affected by ITMS treatment. In conclusion, ITMS tended to reduce the incidence of metritis and stillbirth parturition, improved PMNL function, and improved the inflammatory status of dairy cows undergoing the transition period in high temperature-humidity index conditions. However, these findings did not translate into improved milk yield, reproductive performance, and survivability.
Heat stress during the transition period is associated with impaired production, reproduction, and survival in dairy cows
(2022) Menta, P. R. (TTU); Machado, V. S. (TTU); Piñeiro, J. M.; Thatcher, W. W.; Santos, J. E.P.; Vieira-Neto, A.
Objectives of this retrospective cohort study were to determine the association of heat stress (HS) exposure during the periparturient period with production, health, reproduction, and survival during the first 90 d postpartum in dairy cows. A total of 5,722 Holstein cows (2,324 nulliparous and 3,397 parous) were categorized into environmental condition groups based on average temperature-humidity index (THI) exposure as thermoneutral (TN) or HS during the prepartum (PRE) and early postpartum (POST) periods into TN-TN (THI: PRE = 57.9 and POST = 63.7), TN-HS (THI: PRE = 68.2 and POST = 72.0), HS-TN (THI: PRE = 71.4 and POST = 65.6), and HS-HS (THI PRE = 72.2 and POST = 72.7). Nulliparous and parous cows were analyzed separately. In nulliparous cows, exposure to HS during the PRE, POST, or both PRE and POST periods was associated with a 1.7 kg/cow per day reduction in milk yield compared with TN-TN. Postpartum HS was associated with increases of 4.4 percentage points in incidence of retained placenta, 18.1 percentage points in incidence of metritis, and 2.0 percentage points in incidence of mastitis, but a reduction of 5.3 percentage points in pregnancy at first AI, and an increase of 4.5 percentage points in pregnancy loss compared with POST TN. Exposure to HS during PRE and POST periods was associated with increased removal from the herd. In parous cows, exposure to HS during PRE, POST, or both PRE and POST was associated with a 2.4-kg/cow per day reduction in milk yield when compared with TN-TN. There was an interaction between HS exposure PRE and POST and incidence of retained placenta, because POST HS was associated with an increase in incidence of 5.8 percentage points within PRE HS cows, whereas no difference was found within PRE TN cows. Postpartum HS was associated with an increase of 6.3 percentage points in incidence of metritis and tended to be associated with an increase of 1.9 percentage points in mastitis incidence compared with POST TN. There was an interaction between HS exposure PRE and POST and pregnancy per AI because POST HS was associated with reduced pregnancy incidence by 10.6 percentage points within PRE TN cows, whereas no difference was found within PRE HS cows. Removal from the herd increased in cows exposed to HS during the PRE or POST or PRE and POST. These data suggest that POST HS is associated with performance losses to a greater extent than prepartum HS and that nulliparous and parous cows are prompt to losses associated with exposure to HS during the transition period. The results corroborate findings from manipulative experiments that showed improved milk production and reproduction in cows under HS provided with heat abatement but adds insights to the associations between HS and health.
Plasma oxylipin profile of postpartum dairy cows categorized into different systemic inflammatory grades in the first week after parturition
(2024) Grantz, J. M.; Mukhopadhyay, A.; Jannasch, A. H.; Ferreira, C.; Menta, P. R. (TTU); Machado, V. S. (TTU); Neves, R. C.
Oxygenated polyunsaturated fatty acids (oxylipins) are important mediators of inflammation ranging from pro- to anti-inflammatory actions. Research investigating differences in the oxylipin profile of dairy cows suffering from different degrees of systemic inflammation in the early postpartum period is lacking and can help advance knowledge on potential mechanisms leading to excessive inflammation. The objective of this preliminary study was to evaluate the plasma oxylipin profile of cows classified in 1 of 4 systemic inflammation categories based on plasma haptoglobin (Hp) concentrations assessed on days in milk (DIM) 1, 2, 3, 4, 5, and 7, in addition to the presence or absence of metritis within 10 DIM, and of cows without any clinical diseases within 21 DIM. Groups were classified as follows: (1) cows with a peak Hp concentration ≤3 DIM (EarlyHp) and diagnosed with metritis; (2) cows with a peak Hp concentration 3 < DIM ≤7 (LateHp) and diagnosed with metritis; (3) cows suffering from persistently elevated Hp concentrations assessed on DIM 4 and 7 while remaining apparently healthy during the first 21 DIM (PersistentHp); and (4) apparently healthy cows not suffering from persistently elevated Hp concentrations (LowHp). Six cows from each category were randomly selected from a plasma bank of a parent cohort study including 380 multiparous cows. Plasma samples on DIM 1 and 2, 3 and 4, and 5 and 7 were proportionally pooled to create 3 samples per cow for lipidomic analysis (i.e., pool 1 = DIM 1 and 2; pool 2 = DIM 3 and 4; pool 3: DIM 5 and 7). Statistical analyses were performed using SAS v9.4 (SAS Institute Inc.) and least squares means adjusted for multiple comparisons using the Tukey-Kramer test. Comparisons for EarlyHp and LateHp were only performed on pooled samples from DIM 1 and 2 (i.e., before metritis diagnosis). EarlyHp cows had decreased concentrations of 9(S)-HOTrE compared with LowHp cows of DIM 1–2 pooled samples. LateHp cows had decreased concentrations of 9(10)-DiHOME compared with LowHp cows. Next, we sought to investigate whether cows classified as PersistentHp had time-dependent differences in oxylipin profile versus LowHp cows. PersistentHp cows had decreased concentrations of 19(R)-HETE compared with LowHp cows in a time-dependent manner (only in pooled samples from DIM 5 and 7). Our results identified oxylipins of interest that warrant further investigation to elucidate their in vitro and in vivo functions in the postpartum inflammatory process of dairy cows.
Predictive models for metritis cure using farm-collected data, metabolic and inflammation biomarkers, and hemogram variables measured at diagnosis
(2024) Menta, P. R. (TTU); Prim, J.; de Oliveira, E.; Lima, F.; Galvão, K. N.; Noyes, N.; Ballou, M. A. (TTU); Machado, V. S. (TTU)
Our objective was to evaluate the accuracy of predictive models for metritis spontaneous cure (SC) and cure among ceftiofur-treated cows using farm-collected data only, and with the addition of hemogram variables and circulating concentration of metabolites, minerals, and biomarkers (BM) of inflammation measured at time of diagnosis. Data related to parity, calving-related issues, BCS, rectal temperature, and DIM at metritis diagnosis were collected from a randomized clinical trial that included 422 metritic cows from 4 herds in Texas, California, and Florida. Metritis was defined as the presence of red-brownish, watery, and fetid vaginal discharge, and cure was defined as the absence of metritis 14 d after initial diagnosis. Cows were randomly allocated to receive systemic ceftiofur therapy (2 subcutaneous doses of 6.6 mg/kg of ceftiofur crystalline-free acid on the day of diagnosis and 3 d later; CEF) or to remain untreated (control). At enrollment (day of metritis diagnosis), blood samples were collected and submitted to complete blood count (CBC) and processed for the measurement of 13 minerals and BM of metabolism and inflammation. Univariable analysis to evaluate the association of farm-collected data and blood-assessed variables with metritis cure were performed, and variables with P ≤ 0.20 were offered to multivariable logistic regression models and retained if P ≤ 0.15. The areas under the curve for models predicting SC using farm data only and farm + BM were 0.70 and 0.76, respectively. Complete blood count variables were not retained in the models for SC. For models predicting cure among CEF cows, the area under the curve was 0.75, 0.77, 0.80, and 0.80 for models using farm data only, farm + CBC, farm + BM, and farm + CBC + BM, respectively. Predictive models of metritis cure had fair accuracy, with SC models being less accurate than models predictive of cure among CEF cows. Additionally, adding BM variables marginally improved the accuracy of models using farm collected data, and CBC data did not improve the accuracy of predictive models.