Physiological responses, water consumption, and feeding behaviour of lamb breeds fed diets containing different proportions of concentrate

Abstract

The use of adapted breeds, such as Santa Inês, is of paramount importance for regions with high temperatures because they develop efficient mechanisms for heat dissipation. Furthermore, some breeds have physiological adaptations, such as more efficient mechanisms for the digestion of fibrous foods (e.g. Rabo Largo), which can reduce the harmful effects of semiarid environments. We studied the ingestive behaviour, water consumption, and physiological parameters during feeding of two native sheep breeds fed diets containing high (700 g/kg DM; HC diet) or low (300 g/kg DM; LC diet) percentages of concentrates, based on dry matter (DM). A total of 40 uncastrated male lambs (20 Rabo Largo [breed 1] and 20 Santa Inês [breed 2], with an average body weight of 16.68 ± 2.78 kg, and 19.29 kg ± 3.28 kg, respectively), were distributed in a randomised block design in a two-by-two factorial scheme (breeds × diets) with 10 repetitions. Santa Inês lambs consumed and ruminated DM (P = 0.029 for both) and neutral detergent fibre (NDF; P = 0.001 and P = 0.004, respectively) more efficiently than RaboLargo lambs, while the latter showed an increase in respiratory rate (+19 breaths/min) and rectal temperature (+1.3 °C) compared to the Santa Inês lambs (P = 0.001). The HC diet negatively affected (P < 0.05) the feeding behaviour of the animals, reflecting the higher (P < 0.05) water consumption. The results showed that diets rich in concentrate negatively affected the thermoregulation of lambs. Santa Inês have greater feed and thermoregulatory efficiency than Rabo Largo lambs under conditions of heat stress in the feedlot.

Pre-slaughter management in Northeast Brazil and the effects on thermophysiological indicators in pigs and pH45

“…Finally, the rectal temperature of the pigs was measured after restraint using a "pipe" (instrument routinely used in swine farms) with a digital skewer thermometer with ± 0.5 °C accuracy (−10 to 100 °C, AK05, AKSO), inserted directly into the rectum at a depth where the bulb was in contact with the rectal mucosa (Pereira et al, 2022).…”

Impact of diets containing spineless cactus associated with lipid sources or levels of urea on physiological parameters of lambs: preliminary studies

“…On the other hand, Andrade (2006) stated that an ITGU value of 85.1 cannot be classified as dangerous for Santa Inês sheep due to the high degree of adaptability of these animals to the climatic conditions of semi-arid regions. According to Pereira et al (2022), Santa Inês lambs have high thermoregulatory efficiency under conditions of heat stress in the feedlot.…”