B.S. Bharath Kumar

Age-related changes and circadian variations in peripheral levels of thyroid hormones in Murrah buffaloes

Abstract The aim of this study was to investigate the variations in plasma triiodothyronine (T3) and thyroxine (T4) with the advancement of age and to determine their circadian patterns in prepubertal and pubertal Murrah buffaloes. The variations in plasma T3 and T4 with the advancement of age were observed from day 1 to 24 months of age. Significant higher levels of T3 and T4 were observed after birth and a gradual decrease in their concentrations occurred until 15 days of age. The mean plasma T3 and T4 ranged between 1.26–3.79 and 60.7–166 ng/ml, respectively, during 1–30 days of age. During 1–24 months of age, the variations in plasma T3 did not differ (p > 0.05) with the advancement of age, whereas significant (p < 0.0001) changes were observed in plasma T4. The circadian patterns of T3 and T4 were evaluated in prepubertal Murrah buffaloes (n = 8) aged between 14 and 16 months. The mean plasma T3 and T4 ranged between 1.04–1.85 and 43.0–76.1 ng/ml, respectively. Significant (p > 0.0001) changes in the secretory pattern of T3 were observed, whereas the secretory pattern of T4 did not differ significantly (p > 0.05). In addition, the circadian patterns of T3 and T4 in pubertal buffaloes (n = 4) aged between 28 and 30 months were observed and compared to that of prepubertal group (n = 4). The prepubertal group showed significant (p < 0.001) higher plasma T3 concentrations over 24 h than the pubertal group.

Xanthine oxidase activity during transition period and its association with occurrence of postpartum infections in Murrah buffalo (Bubalus bubalis)

The aim of this study was to quantify xanthine oxidase (XO) levels during the transition period in Murrah buffalo (Bubalus bubalis) and determine its association with certain postpartum infections. For this, six healthy buffaloes were selected from the National Dairy Research Institute (NDRI) herd and managed under standard managemental practices as followed at the institute. Blood samples were drawn weekly from each buffalo from day -21 to +21 relative to parturition by jugular vein puncture. Additional blood samples were collected from buffaloes suffering from metritis (n=5), endometritis (n=6) and mastitis (n=8) on alternate days. XO activity followed a defined pattern with values gradually declining from day -21 up to the day of calving followed by an increase to day +21, but the difference was statistically not significant between pre- and post-partum stages. The activity significantly declined on the day of calving when compared to the pre-partum mean value (p<0.05). The activity was significantly enhanced in buffaloes with bacterial infections, endometritis, and mastitis compared to healthy controls (p<0.05). However, the levels were not significantly altered among buffalo with metritis. The results indicate that increased XO activity during the postpartum period was associated with some bacterial infections in buffaloes, which could be due to increased phagocytic activity as a part of the innate defense system. Keywords : Xanthine oxidase, transition period African Journal of Biotechnology Vol. 12(32), pp. 5101-5104

Age-related and seasonal variations in plasma uncarboxylated osteocalcin in male Murrah buffaloes

Abstract The present study aims to investigate the age-related and seasonal variations in plasma uncarboxylated osteocalcin (UcOCN) in male Murrah buffaloes. In experiment 1, body weight, body dimensions and plasma UcOCN levels were estimated in 120 male Murrah buffaloes aged between 18 days and 8 years. We observed a significant (p < 0.0001) decrease in plasma UcOCN with age and their levels ranged between 0.25 and 9.25 ng/ml. In experiment 2, the plasma UcOCN, cortisol, triiodothyronine (T3), thyroxine (T4) and prolactin levels were determined during spring and summer in 6–34 months (n = 24) old male Murrah buffaloes. Significant (p < 0.0001) higher plasma UcOCN levels were observed in spring than in summer. The plasma T3 and T4 levels were positively correlated with plasma UcOCN, whereas the plasma cortisol and prolactin were negatively correlated. Further, to observe the effect of season on temporal variations of UcOCN, Murrah buffaloes aged between 4–6 (n = 5), 14–16 (n = 5) and 28–30 (n = 5) months were bled at an interval of 30 min, between 0700 and 01030 h, during both the seasons. We observed significant effects of season (p < 0.0001), age (p < 0.0001) and season-by-age interaction (p < 0.01) on plasma UcOCN. The reasons for variations in plasma UcOCN with age and season will be discussed.

Circadian variations in peripheral levels of growth hormone and testosterone in male Murrah buffaloes

Abstract The aim of this study was to investigate the endocrine profiles of growth hormone (GH), testosterone and their interrelationship in prepubertal, pubertal and orchiectomised male Murrah buffaloes under starving conditions. The prepubertal and pubertal buffaloes were subjected to frequent blood sampling over 24 h at an interval of 1 h, whereas in orchiectomised buffaloes, the blood samples were collected over 18 h. Irrespective of group, the GH concentrations fluctuated in an episodic manner over 24 h and the fluctuations did not exhibit a consistent pattern between the animals of each group. The mean basal and peak concentrations of GH did not differ significantly (p > 0.05) among the groups. A significant (p > 0.0001) difference in testosterone concentrations was observed between prepubertal and pubertal groups. The differences in mean basal and peak testosterone concentrations between the prepubertal and pubertal groups were also significant (p < 0.01). The associations between testosterone and GH levels in both prepubertal (r = 0.15; p > 0.05) and pubertal (r = −0.37; p > 0.05) buffaloes were non-significant. The possible reasons for erratic episodic pattern of GH secretion will be discussed.

EFFECT OF VITAMIN E SUPPLEMENTATION TO DRY MURRAH BUFFALOES ON DRY MATTER INTAKE, BODY CONDITION SCORE, METABOLIC SHIFTS PRE AND POSTPARTUM

This study as designed to evaluate effect of vitamin E supplementation to dry Murrah buffaloes on dry matter intake, body condition score and metabolic shifts pre and postpartum in response to vitamin E supplementation from day -56, relative to parturition. Total twelve numbers of healthy dry Murrah buffaloes were selected from National Dairy Research Institute Murrah herd and randomly distributed in to two groups treatment and control consisting six buffaloes in each group. Buffaloes in treatment group were supplemented with 2,000 IU α-tocopheryl acetate/day/head from -56 days prepartum to + 21 days postpartum in addition to the control feed. Dry matter intake, body weight and body condition score were recorded at fortnightly interval. Blood samples were taken from each buffalo by jugular vein puncture at weekly interval from day -56 to day + 56 relative to parturition. Vitamin E supplemented buffaloes registered significantly higher levels of glucose (P < 0.05) and albumin (P < 0.05) whereas plasma NEFA and DMI was low in these buffaloes. There was no effect of vitamin E supplementation on body weight, BCS, β-HBA and BUN levels. The changes occurring in peripheral levels of these blood metabolites were within the normal physiological range in both the groups.