Features of the formation of lambs' adaptive capacity in the first day of life

Abstract

New-born lambs are subjected to significant loads during rearing with the existing technologies of sheep farming. The stability and ability to adapt of newborn animals is not the same and is conditioned by different functional maturity, low resistance, and high susceptibility to extreme biotic and abiotic factors. Because of this, their physiological condition deteriorates, the body defenses decrease, which most often leads to a decrease in productivity, an increase in morbidity and mortality. Knowledge about the development of the clinical condition and thermoregulation in lambs during early ontogenesis is quite limited, which determines the relevance and expediency of the work conducted, the purpose of which was to investigate the peculiarities of the formation of adaptive capacity in newborn lambs during the first day of postnatal rearing. As part of the experiment, it has been determined that the body temperature of the lambs on the first day after birth varied with different intensity from the initial value. This was affected by the differences in the modules of its deviation, which made it possible to distinguish three groups with different levels of thermoregulation processes. Lambs of group I were the most viable, which were born with 5.1 and 9.9% more live weight at a higher metabolic rate of 1.0378 vs. 1.0331 and 1.0300 in lambs of groups II and III and reliably higher by 5.0 and 14.9% of pulse rate parameters and 4.7 and 27.7% of breathing rhythm, thereby ensuring sufficient functioning of thermoregulation mechanisms. It was found that the level and nature of the correlation between live weight and physiological indicators (live weight, pulse and breathing rates) indicate the multi-vector relationship in lambs with different body temperature deviation modules. These dependencies were especially clearly manifested in individuals of the group I (r=-0.522; r=0.362; r=0.707, respectively). It was recorded that the microclimate in the room for keeping ewes and newborn lambs in terms of hydrogen sulfide content almost twice exceeded the technological norm of industry-specific process engineering standard, while other zoohygienic parameters approached its upper limit.