Venous blood gas parameters in healthy Mediterranean buffalo calves in the first 72 hours of life

Strategies and Mechanisms of Thermal Compensation in Newborn Water Buffaloes

Hypothermia is one of the principal causes of perinatal mortality in water buffaloes and can range from 3% to 17.9%. In ruminants, factors affecting hypothermia in newborns may be of intrinsic (e.g., level of neurodevelopment, birth weight, vitality score, amount of brown fat, skin features) or extrinsic origin (e.g., maternal care, environmental conditions, colostrum consumption). When newborn buffaloes are exposed to cold stress, thermoregulatory mechanisms such as peripheral vasoconstriction and shivering and non-shivering thermogenesis are activated to prevent hypothermia. Due to the properties of infrared thermography (IRT), as a technique that detects vasomotor changes triggered by a reduction in body temperature, evaluating the central and peripheral regions in newborn buffaloes is possible. This review aims to analyze behavioral, physiological, and morphological strategies and colostrum consumption as thermal compensation mechanisms in newborn water buffalo to cope with environmental changes affecting thermoneutrality. In addition, the importance of monitoring by IRT to identify hypothermia states will be highlighted. Going deeper into these topics related to the water buffalo is essential because, in recent years, this species has become more popular and is being bred in more geographic areas.

Milk yield variation partially attributed to blood oxygen-mediated neutrophil activation in lactating dairy goats

Blood oxygen is an essential component for numerous biological processes of mammalian animals. Milk production of ruminants largely relies on the supply of nutrients, such as glucose, amino acids and fatty acids. To define the regulatory role of blood oxygen availability in regard to milk production, seventy-five healthy Guanzhong dairy goats with similar body weight, days in milk and parities were selected. For each animal, milk yield was recorded and milk sample was collected to determine compositions. Milk vein blood was collected to determine parameters including blood gas, physio-biochemistry and haematology. Another blood sample was prepared for transcriptome and RT-qPCR. Results showed that both pressure of oxygen (pO₂) in the milk vein (positively) and numbers of neutrophils in mammary vein (negatively) were associated with milk yield of the animals. To learn the role of pO₂ in blood cell functionality, twelve animals (six with higher yield (H-group) and six with lower yield (L-group)) from seventy-five goats were selected. Compared with animals in L-group, goats in H-group were higher in pO₂ but lower in pCO₂, lactate, lactate dehydrogenase activity and neutrophil abundance in milk vein, compared with L-group. The blood transcriptome analysis suggested that compared with L-group, animals in H-group were depressed in functionality including neutrophil activation and metabolic pathways including glycolysis, NF-κB and HIF-1. Our result revealed that lower milk production could be associated with neutrophil activation responding to low pO₂ in the mammary vein. In the meantime, we highlighted the potential importance of blood oxygen as a milk yield regulator.

Dairy Buffalo Behavior: Calving, Imprinting and Allosuckling

Maternal behavior, in water buffalo and other ruminants, is a set of patterns of a determined species, including calving, imprinting, and suckling. This behavior is mainly triggered by hormone concentration changes and their interactions with their respective receptors in the brain, particularly oxytocin. These chemical signals also influence mother-young bonding, a critical process for neonatal survival that develops during the first postpartum hours. Currently, dairy buffalo behavior during parturition has rarely been studied. For this reason, this review aims to analyze the existing scientific evidence regarding maternal behavior in water buffalo during calving. It will address the mechanisms of imprinting, maternal care, and allosuckling strategies that may influence the survival and health of calves.

Evaluation of Brix Refractometry to Estimate Immunoglobulin G Content in Buffalo Colostrum and Neonatal Calf Serum

Simple Summary

The protective effects of colostrum in relation to the incidence and severity of newborn ruminant diseases are well established. Neonatal calf depends on the timely supply of high-quality colostrum to prevent the failure of passive transfer of immunoglobulins (Ig), which has been linked to increased risk of different diseases and mortality in early stages of life. Despite the relevance of Buffaloes (Bubalus Bubalis) in world dairy production, the available knowledge regarding colostrum quality management remains scarce for this species. Therefore, the objective of this study was to evaluate the utility of a simple and rapid tool such as a digital Brix refractometer to estimate colostrum quality and for predicting the success of passive transfer of immunoglobulin G (IgG) in Buffalo calves. For this aim, correlation analysis was performed between Brix results and ELISA-IgG determination from colostrum and serum samples. A strong correlation was found between Brix measurements and IgG content in colostrum and serum samples. Moreover, cut point values for Brix measurements for colostrum and serum samples were determined. Brix refractometry was found to be an acceptable tool for on-farm estimations of colostrum quality and passive immunity transfer (PIT) in Buffalo calves.

Abstract

Brix refractometry has been widely demonstrated to be a useful tool for monitoring colostrum management program and passive immunity transfer (PIT) in Bovines, but its suitability has never been verified in Buffalo. Therefore, the objective of this study was to evaluate the utility of a simple and rapid tool such as a digital Brix refractometer to estimate colostrum quality and for evaluating the success of passive transfer of immunoglobulin G (IgG) in Buffalo calves. The optimal cut points levels for Brix Refractometry for distinguishing good- and poor-quality colostrum and for assessing the adequacy of passive immunity transfer in calves were determined. For this aim, 26 first-milking maternal colostrum (MC) were collected from first-calf heifers. Blood samples were obtained from their calves at birth (T0) and 72 hours after (T3). Colostrum and Serum IgG content were determined by indirect enzyme-linked immunosorbent assay (ELISA), whereas total protein (TP, g/dL) and percentage Brix (%Brix) by means of a digital Brix refractometer. The mean colostrum IgG was 64.9 ± 29.3 mg/mL. The mean serum %Brix at T3 was 9.6 ± 0.9 %. The mean serum IgG content at T3 was 11.1 ± 2.0 mg/mL. Pearson’s correlation coefficient (r_p) was determined between Brix and ELISA measurements: colostrum %Brix showed a significant correlation with serum %Brix (r_p = 0.82, p < 0.001); serum %Brix was highly correlated with serum TP (STP, g/dL) (r_p = 0.98, p < 0.001) and serum IgG (mg/mL) (r_p = 0.85, p < 0.001). A cut point of 18% Brix to estimate samples of MC ≥ 50 mg/mL from first-calf heifers was more appropriate for the buffalo. A cut point of 8.4% Brix resulted in the greatest percentage of calf serum samples being correctly classified. Based on our findings, a digital Brix refractometer could be a useful tool to monitor colostrum quality and to estimate PIT in Buffalo calves.

Maternal and Neonatal Behaviour in Italian Mediterranean Buffaloes

The aim of this study was to describe the neonatal and maternal behaviour of Italian Mediterranean buffaloes. Thirty primiparous buffaloes were moved into individual pens 12.5 (±2.5) days before calving. Maternal and neonatal behaviours were recorded for 48 h after calving and the analysis was performed in continuous sampling with the software BORIS. Calves' clinical evaluations (temperature, weight, and heart and respiratory rates) were performed at different time intervals and correlated with behavioural data from the dam. Data were analysed with parametric and non-parametric methods after controlling their distribution. The maternal behavioural pattern found highlighted buffaloes' priorities during the post-partum period: firstly, they stand and start grooming to ensure proper care for the calf; it is only after this that they dedicate time to maintenance behaviours (feeding and lying). The dams mainly groomed the calf during the first six hours after calving (average time in the 1-6-h interval: 7.7 ± 2.5 min., F = (2.5, 60.2) = 75.0; p < 0.001) to ensure the formation of the mother-infant bond; thereafter, the behaviour decreased over time. As reported in the literature, inexperienced mothers could sometimes delay the calf's first suckling with aggressive or rejection behaviours. In this regard, 16 buffalo dams showed at least one maternal rejection behaviour, which was found to negatively correlate with calves' daily weight gain (DWG) at 14 (r_s = -0.5, p = 0.02) and 21 days (r_s = -0.7, p < 0.001). The calves took on average 212.0 ± 110.0 min to suckle, and this behaviour was mainly shown during the first six hours. Overall, suckling behaviour was correlated with standing: (r_s = 0.6, p < 0.001) and walking (r_s = 0.9, p < 0.001). The calves' live weight and DWG were consistently higher than the values reported in the literature. Our results present a detailed description of maternal and neonatal behaviour in the early post-partum period in Italian Mediterranean buffaloes. We also found that maternal rejection behaviours can negatively influence the calves' growth. Finally, we think that such results can improve the management of buffaloes during the period around parturition.