High serum free fatty acids and low leptin levels: Plausible metabolic indicators of negative energy balance in early lactating Murrah buffaloes

Blood profile, hormones, and telomere responses: potential biomarkers in horses exhibiting abnormal oral behaviour

The high prevalence of abnormal oral behaviour (AOB) in working horses has been linked to management issues and the pathophysiology of this behaviour remains unclear. Therefore, this study aims to elucidate the blood profile, hormones, and telomere length responses between low and high levels of AOB among different horse working groups. A total of 207 healthy horses from various breeds were initially selected from four working groups (leisure riding, equestrian, endurance, and patrolling) and observed for the time spent on AOB. Then, six horses each with higher and lower AOB than the population means were randomly selected from each of the working groups and categorized as high and low AOB horses, respectively. Blood samples were collected for haematology, biochemistry, cortisol, ghrelin, leptin, and relative telomere length analyses. High AOB horses notably had higher values of glucose, alanine aminotransferase (ALT), alkaline phosphatase (ALP), and creatine kinase (CK) compared to low AOB horses. High AOB horses also recorded higher plasma cortisol and ghrelin, but lower leptin concentrations. Among working groups, both endurance and patrolling horses presented the highest values in sodium, potassium, chloride, phosphate, ALT, and CK. While patrolling horses had the lowest levels of urea, ALP, and albumin levels, equestrian and leisure horses recorded the highest and lowest plasma cortisol and leptin concentrations, respectively. Finally, the telomere length of endurance and patrolling horses were significantly greater than leisure and equestrian horses. The present findings suggest that AOB horses had distinctive physiological characteristics that could be linked to improper diet and a demanding workload, while ghrelin and leptin hormones could be potential biomarkers for this behaviour.

Acute phase proteins and markers of oxidative status in water buffalos during the transition from late pregnancy to early lactation

The transition period, from pregnancy to lactation, implies comprehensive metabolic and endocrine changes including a systemic inflammatory reaction and oxidative stress around calving in dairy cows. The aim of the present study was a longitudinal characterization of the serum concentration of acute phase proteins (APP), i.e., haptoglobin (Hp), serum amyloid A (SAA) and acidic glycoprotein (AGP), as well as of markers for oxidative stress in another large dairy animal, i.e. water buffalo, during the transition from late pregnancy to early lactation. As indicators of oxidative status, derivatives of reactive oxygen metabolites (dROM), ferric reducing ability (FRAP), thiobarbituric acid reactive substances (TBARS), and advanced oxidation protein products (AOPP) were determined in serum. Indicators for metabolic stress included nonesterified fatty acids (NEFA), ß-hydroxybutyrate (BHB) and adiponectin. Bovine specific ELISA methods for Hp and adiponectin were adapted and validated for their application to water buffalo samples. Blood samples were collected weekly from 11 pluriparous water buffalo cows (lactation number 4.6 ± 1.6; daily milk yield 9.0 ± 1.9 kg; means ± SD) from 6 weeks (wk) ante partum (ap) until 8 wk post partum (pp). The maximum concentrations of Hp were observed in wk 1 pp, followed by a decrease towards values lower than before calving starting from wk 3 pp. The concentrations of SAA also peaked in wk 1 pp and then returned to basal values. The AGP serum concentrations increased suddenly from the first to the second wk pp and remained elevated for all the observation period. Indicators of oxidative status which changed in concentration during the transition period were dROM, AOPP and the oxidative stress index (OSi) (dROM/FRAP ratio). Briefly, dROM and AOPP values were lower pp as compared to ap, and OSi was largely following the pattern of dROM due to the constant FRAP values. The TBARS values did not change during the observation period. From the metabolic indicators, adiponectin was not changing with time, whereas greater NEFA and BHB values were observed ap than pp. The time course of NEFA and of some indicators for oxidative status (dROM, OSi and AOPP) point to greater metabolic load in late pregnancy as compared with the first wk of lactation - contrary to the common situation in dairy cows. Both BHB and NEFA values remained below the thresholds applied for dairy cows to define subclinical or clinical ketosis, thus indicating that the buffaloes included in this study were not under metabolic stress. The increase in concentration of the APP around calving supports the concept that an inflammatory reaction is a physiological epiphenomenon of the onset of lactation in water buffalos that is independent of metabolic stress.

Non-esterified fatty acids in the ovary: friends or foes?

A majority of common metabolic diseases can result in excessive lipolysis, leading to elevated levels of non-esterified fatty acids (NEFAs) in the body fluids. In females, increased NEFA levels in the follicular fluid markedly alter the functions of intrafollicular cells such as granulosa cells (GCs) and oocytes. Therefore, elevated levels of NEFAs have been suggested to be a significant player of subfertility in females of both human and economically important animal species such as cattle, buffalo, sheep, pig, chicken, and dog. However, the effects imposed by saturated and unsaturated fatty acids (SFAs and UFAs) on ovarian follicles are controversial. The present review emphasizes that SFAs induce apoptosis in granulosa and cumulus cells of ovarian follicles in different species. They further could adversely affect oocyte maturation and developmental competence. Many types of UFAs affect steroidogenesis and proliferation processes and could be detrimental for follicular cells, especially when at elevated concentrations. Interestingly, monounsaturated fatty acids (MUFAs) appear to contribute to the etiology of the polycystic ovarian syndrome (PCOS) as they were found to induce the transcription and translation of the androgenic transcription factor SOX9 while downregulating its estrogenic counterpart FOXL2 in GCs. Overall, this review presents our revised understanding of the effects of different fatty acids on the female reproductive success, which may allow other researchers and clinicians to investigate the mechanisms for treating metabolic stress-induced female infertility.

Milk yield at first lactation, parity, and season of calving affect the reproductive performance of water buffalo cows

Context Profitability of water buffalo systems depends on a calving interval (CI) <400 days. Several factors affect the achievement of this target. However, milk yield at first lactation has received little attention. Aims Determine the effect of milk yield at first lactation, parity, season of calving and farm, on the length of CI and the probability of a CI ≤ 400 days in water buffaloes. Methods A retrospective analysis of milk yield at first lactation and reproductive records of 1459 water buffaloes was carried out. Milk yield was categorised as Group 1 (≤1090 kg), Group 2 (1090–1377 kg), Group 3 (1377–1684 kg) and Group 4 (>1684 kg); parity was categorised as parity 1, 2 and ≥ 3; and month of calving was grouped into three seasons: December–March, April–July, and August–November. Data were analysed using linear and logistic mixed models. Key results CI increased from 425.3 days (95% CI: 418.8–431.8 days) in group 1 to 463.3 days (95% CI: 456–470.6 days) in group 4 (P < 0.05), while the probability of having a CI ≤ 400 days decreased from 0.5 (95% CI: 0.46–0.54) to 0.26 (95% CI: 0.22–0.29), respectively (P < 0.05). CI decreased from 466 days (95% CI: 460.8–471.3 days) in parity 1 to 410.5 days (95% CI: 405.2–415.8 days) in parity ≥3, whereas the probability of a CI ≤ 400 days increased from 0.26 (95% CI: 0.24–0.29) to 0.51 (95% CI: 0.47–0.54) respectively (P < 0.05). Water buffaloes calving in August–November showed significantly shorter CI and, along with those calving between December–March, showed the highest probability of a CI ≤ 400 days. An interaction between milk yield at first lactation and parity on both outcomes was observed. Conclusions Shorter CI and higher probability of a CI <400 days were associated with lower milk yields at first lactation, higher parity and calving between August–November. Higher milk yield at first lactation affected negatively the reproductive performance of water buffaloes, especially at parity 1 and 2. Implications These results highlight the importance of adequate nutritional management to allow water buffaloes to cope with the challenge of the postpartum negative energy balance and have a calving interval less than 400 days.