A. Manimaran

Identification of putative fertility markers in seminal plasma of crossbred bulls through differential proteomics

Sub-fertility is a major problem in crossbred bulls leading to disintegration of breeding systems and huge economic loss. Identification of some potential biomarkers to determine the latent fertility of bulls accurately has long been the interest of researchers. In this study, we analyzed the proteome of seminal plasma (SP) from bulls with varying fertility to identify the fertility-associated proteins. The proteomic profile of high- and low-fertile bulls was compared by two-dimensional difference gel electrophoresis and differentially expressed proteins were identified through matrix-assisted laser desorption/ionization-time of flight/mass spectrometry. Out of the 18 differentially expressed proteins (P < 0.05), 9 were overexpressed in SP of high-fertile bulls and 9 were overexpressed in SP of low-fertile bulls. The differential expressions ranged from 1.5- to 5.5-fold between the two groups, where protection of telomeres-1 protein (POT1) was highly overexpressed (2.9-fold) in high-fertile group and prostaglandin E2 receptor EP3 (PTGER3) was highly abundant (5.5-fold) in low-fertile group. The protein interaction network was elucidated using STRING software tool, and the functional bioinformatics analysis was done using Blast2Go software. Most of the differentially expressed proteins were found to be involved in cellular processes and biological regulation with binding and catalytic function. It is inferred that the expression of certain proteins in the SP varied with bull fertility, and concurrent appraisal of their expression along with other fertility assays may help in determining bull fertility.

Effects of pedigree and exotic genetic inheritance on semen production traits of dairy bulls

Abstract Objective To study the effects of different levels of exotic inheritance on ejaculate quality in bulls and its passage through different generations. Methods Data on semen production traits and ejaculate quality were obtained for 38 crossbred bulls and grandsire-sire-progeny relationship in relation to semen quality was studied. The bulls were classified into three groups based on the level of exotic inheritance viz. F1, 50.0%-62.5% exotic germplasm and >75% exotic germplasm. Results Results of the present study indicated that about 40% of the ejaculates obtained from the crossbred bulls were rejected from further processing due to poor ejaculate quality. The F1 bulls produced significantly higher proportions (57.00±10.00) of poor quality ejaculates compared to the interse mated bulls. The age at first semen collection in crossbred bulls ranged from 567 to 1 010 days with an average of 738.89±18.18 days while the mean age at first semen freezing was 865.72±34.60 days. Conclusions It may be inferred that the “acceptable quality semen producing ability” decreased from grandsire through sire to male progeny and among the increasing exotic genetic levels of CB cattle, F1 bulls produced significantly higher “low grade ejaculates” that were unfit for cryopreservation.

Mastitis effects on reproductive performance in dairy cattle: a review

The reproductive performance of dairy animals is influenced by several factors, and accumulating lines of evidence indicate that mastitis is one of the determinants. Most of the published information relating mastitis with reproduction has evolved based on retrospective approach rather than controlled clinical studies. The complex nature of both mastitis and reproduction could be a limiting factor for understanding their relationship in detail. In this review, we analyzed the available retrospective studies on the effects of clinical mastitis on reproductive function and explained the possible mechanisms by which mastitis affects reproduction in dairy animals.

Alterations in cortisol concentrations and expression of certain genes associated with neutrophil functions in cows developing retention of fetal membranes

Elevated cortisol concentrations have been reported to impair the functions and alter the life span of neutrophils in cows. The present study assessed the cortisol concentrations and expression of few genes related to longevity (Fas, Caspase 3, Bcl2) and margination (CD 62L, CD 18/11b) of neutrophils in relation to retention of fetal membranes (RFM) in dairy cows. Cortisol concentrations were significantly higher on the day of calving and day 2 postpartum in RFM cows than normal cows. Expression of CD 62L was significantly lower on the day of calving and day 2 postpartum in RFM cows than normal cows. While expression of Fas and GR was significantly lower on the day of calving, expression of Bcl2 was lower on day 7±2 pre-partum in RFM cows compared to normal cows. No significant difference was observed in the expression of CD 18/11b and Caspase 3 between RFM and normal cows. Cortisol concentration was negatively correlated with expression of GR, Fas, CD 62L, CD18/CD11b and Caspase 3, while positively correlated with immature neutrophil percentage and expression of Bcl2. It may be inferred that cortisol concentrations and expression of certain genes associated with lifespan and margination of neutrophils were altered in cows developing RFM compared to those expelled the fetal membranes normally.

Alteration in peripheral blood concentration of certain pro-inflammatory cytokines in cows developing retention of fetal membranes

Retention of fetal membranes (RFM) adversely affects the production and reproduction potential of the affected cows leading to huge economic loss. Physiological separation of fetal membranes is reported to be an inflammatory process. The present study compared the concentrations of certain pro inflammatory cytokines [Interleukin 1β (IL-1), Interleukin 6 (IL-6), Interleukin 8 (IL-8) and Tumor necrosis factor α (TNF-α) between the cows that developed RFM (n=10) and the cows that expelled fetal membranes normally (n=10) to find out if they could serve as a predictive tool for RFM. Blood samples were collected from the cows from 30 days before expected parturition through day -21, day -14, day -7, day -5, day -3, day -1, on the day of parturition (day 0), day 1 postpartum and the pro-inflammatory cytokines were estimated in blood plasma by ELISA method. The IL-1β concentration was significantly lower (P<0.05) in cows that developed RFM compared to those that expelled fetal membranes normally from 3 days before calving till the day of calving. The plasma concentrations of IL-6 and IL-8 were also lower (P<0.05) in cows that developed RFM than those calved normally. On the day of calving, significantly (P<0.05) lower concentrations of TNF-α was observed in cows that developed RFM compared to those expelled fetal membranes normally. It may be inferred that the concentrations of IL-1, IL-6, IL-8 and TNF-α around parturition were altered in cows developing RFM compared to those expelled fetal membranes normally.

Infrared thermography: A potential noninvasive tool to monitor udder health status in dairy cows

The animal husbandry and livestock sectors play a major role in the rural economy, especially for the small and marginal farmers. India has the largest livestock population in the world and ranks first in the milk production. Mastitis is the most common and expensive infectious disease in dairy cattle. The global economic losses per year due to mastitis amounts to USD 35 billion and for Indian dairy industry ₹6000 crores per year. Early detection of mastitis is very important to reduce the economic loss to the dairy farmers and dairy industry. Automated methods for early and reliable detection of mastitis are currently in focus under precision dairying. Skin surface temperature is an important indicator for the diagnosis of cow’s illnesses and for the estimation of their physiological status. Infrared thermography (IRT) is a simple, effective, on-site, and noninvasive method that detects surface heat, which is emitted as infrared radiation and generates pictorial images without causing radiation exposure. In human and bovine medicine, IRT is used as a diagnostic tool for assessment of normal and physiological status.

Metabolic indicators for retention of fetal membranes in Zebu and crossbred dairy cattle

The present study assessed the peripartum metabolic profile of Karan Fries crossbred (Holstein Friesian × Tharparkar) and Zebu (Sahiwal) cows in relation to expulsion of fetal membranes. Peripheral blood concentrations of glucose, total protein, total cholesterol, blood urea nitrogen, non-esterified fatty acid (NEFA) and β-hydroxy butyric acid (BHBA) were determined (from 30 days before and 2 days after calving) in cows that expelled fetal membranes normally (n = 13; 7 crossbred and 6 Zebu cows) and in cows that developed retention of fetal membranes (RFM; n = 13; 7 crossbred and 6 Zebu cows). In both breeds, the cows that developed RFM had significantly lower concentrations of cholesterol, glucose and total protein, while the concentrations of NEFA, BHBA and blood urea nitrogen were significantly (P < 0.05) higher than those in cows that normally expelled the fetal membranes. In crossbred cows affected with RFM, the concentrations of NEFA increased significantly (P < 0.05) from Day 14 prepartum to Day 2 postpartum and the concentrations of BHBA increased from Day 7 prepartum to Day 2 after calving. Similarly, in Zebu cows, NEFA and BHBA concentrations increased significantly (P < 0.05) between Day 5 prepartum and Day 2 postpartum in RFM cows. Using receiver operator characteristic analysis, we observed that the concentrations of NEFA and BHBA before calving were highly related to the RFM. It may be inferred that monitoring the levels of NEFA and BHBA during prepartum period would help in identifying the cows at the risk of developing RFM.

Investigation of body and udder skin surface temperature differentials as an early indicator of mastitis in Holstein Friesian crossbred cows using digital infrared thermography technique

Aim: The objective of this study was to investigate the ability of infrared thermography (IRT) technique and its interrelationship with conventional mastitis indicators for the early detection of mastitis in Holstein Friesian (HF) crossbred cows. Materials and Methods: A total of 76 quarters of lactating HF crossbred (Bos indicus × Bos taurus) cows (n=19) were monitored for body temperature (i.e., eye temperature) and udder skin surface temperature (USST) before milking using forward-looking infrared (FLIR) i5 camera. Milk samples were collected from each quarter and screened for mastitis using Somatic Cell Count (SCC), Electrical Conductivity (EC), and California mastitis test. Thermographic images were analyzed using FLIR Quick Report 1.2 image analysis software. Data on body and USST were compiled and analyzed statistically using SPSS 16.0 and Sigmaplot 11. Results: The mean±standard deviation (SD) body (37.23±0.08°C) and USST (37.22±0.04°C) of non-mastitic cow did not differ significantly; however, the mean USST of the mastitis-affected quarters were significantly higher than the body temperature and USST of unaffected quarters (p<0.001). The mean±SD USST of the subclinical mastitis (SCM) and clinical mastitis-affected quarters were 38.08±0.17 °C and 38.25±0.33 °C, respectively, which is 0.72 and 1.05 °C higher than the USST temperature of unaffected quarters. The USST was positively correlated with EC (r=0.95) and SCC (r=0.93). The receiver operating characteristic curve analysis revealed a higher sensitivity for USST in early prediction of SCM with a cut-off value of >37.61°C. Conclusion: It is concluded that infrared thermal imaging technique could be used as a potential noninvasive, quick cow-side diagnostic technique for screening and early detection of SCM and clinical mastitis in crossbred cows.

Potential of acute phase proteins as predictor of postpartum uterine infections during transition period and its regulatory mechanism in dairy cattle.

Among the various systemic reactions against infection or injury, the acute phase response is the cascade of reaction and mostly coordinated by cytokines-mediated acute phase proteins (APPs) production. Since APPs are sensitive innate immune molecules, they are useful for early detection of inflammation in bovines and believed to be better discriminators than routine hematological parameters. Therefore, the possibility of using APPs as a diagnostic and prognostic marker of inflammation in major bovine health disorders including postpartum uterine infection has been explored by many workers. In this review, we discussed specifically importance of postpartum uterine infection, the role of energy balance in uterine infections and potential of APPs as a predictor of postpartum uterine infections during the transition period and its regulatory mechanism in dairy cattle.

Episodes of clinical mastitis and its relationship with duration of treatment and seasonality in crossbred cows maintained in organized dairy farm

Aim: Present study aimed to evaluate the different episodes of clinical mastitis (CM) and influence of duration of treatment and seasonality on the occurrence of different episodes of CM in crossbred cows. Materials and Methods: A total of 1194 lactation data of crossbred CM cows were collected from mastitis treatment record from 2002 to 2012. Data of CM cows were classified into types of episodes (pattern of repeated or multiple episodes occurrence) and number of episodes (magnitude of multiple cases). Types of episodes were divided as single (clinical cure by a single episode of treatment), relapse (retreatment of the same cow within 21 days), recurrence (new CM at least 21 days after treatment), and both (relapse and recurrence). The season was classified as winter (December to March), summer (April to June), rainy (July to September), and autumn (October to November). The difference between incidences of different types of CM episodes and the association between number or type of CM episodes with duration of treatment and seasons of CM occurrence were analyzed by Chi-square test. Results: Among 1194 animals suffered with CM, 53, 16, and 18% had the single episode, relapse, and recurrence, respectively; while 13% suffered by both relapse and recurrence. We estimated the duration of treatment and found 80% of the cows treated 1-8 days, in which 65% treated for 1-4 days, while 35% cows were treated for 5-8 days. Further, 12% cows treated for 9-15 days and 7.5% cows treated >15 days. The relationship between duration of treatment and different episodes of CM revealed that 1-8 days treated cows were mostly cured by the single episode with less relapse and recurrence. In contrast, the incidences of recurrence and relapse episodes were higher in cows treated for more than 9 days. The highest incidence of relapse was noticed in winter (36%) than other seasons (10-28%), while the recurrence was less during autumn (9%) compared to other seasons (20-40%). Conclusion: Cows those suffered by both relapse and recurrence were more susceptible to CM, and they need to be culled from farm to control the transmission of infections. Although the influence of seasonality was difficult to understand, the higher magnitude of relapse and recurrence during winter suggested the adverse effects of cold stress on treatment outcome.