Heat stress impact on blood biochemical response and plasma aldosterone level in three different indigenous goat breeds

Abstract

A study was conducted to compare the adaptive ability of three indigenous goat breeds (Osmanabadi, Malabari, and Salem Black) to heat stress. The primary objective of the study was to assess the thermo-tolerant ability of these breeds to heat stress based on the changes in their blood biochemical response and aldosterone concentration. Thirty six-ten months to one year old female goats were randomly allocated into six groups of six animals each as OCON (n=6; Osmanabadi control), OHS (n=6; Osmanabadi heat stress), MCON (n=6; Malabari control), MHS (n=6; Malabari heat stress), SCON (n=6; Salem Black control) and SHS (n=6; Salem Black heat stress). The OCON, MCON, and SCON animals were maintained in the shed while OHS, MHS, and SHS animals were exposed to summer heat stress between 10:00 h to 16:00 h. All the animals had access to ad-libitum feed and water. The duration of the study was 45 days. The results indicated that breed differences (P < 0.01) were established for the levels of plasma glucose, total protein, albumin, and globulin. However, heat stress treatment did not influence these variables. Further, heat stress significantly increased (P < 0.05) plasma cholesterol only in the MHS group. Besides, albumin/globulin (A/G) ratio, plasma urea, and plasma urea nitrogen (PUN) did not show any significant variation both among and within the breed for the treatment. However, plasma triglyceride was significantly lower (P < 0.05) in both OHS and SHS groups as compared to their respective control groups. Further, aspartate aminotransferase (AST) showed significant variation for the breed (P < 0.05) as well as treatment (P < 0.05) with a higher concentration in the OHS group. Among the breeds, heat stress induced lower (P < 0.05) plasma aldosterone was established only in the MHS group. Thus, it can be concluded from the results that the Malabari breed which was well known for its survival in a harsh environment in its native tract could not adapt well to the new locality with a much lower magnitude of heat stress. However, Salem Black breed could exhibit superior adaptability to the new agro-ecological zone which was comparable to that of local Osmanabadi breed.

Effects of Restricted Availability of Drinking Water on Blood Characteristics and Constituents in Dorper, Katahdin, and St. Croix Sheep from Different Regions of the USA

“…Heat-stress-related dehydration reduced aldosterone concentration in Malabari goats but not in Osmanabadi and Salem Black goats. It has been suggested that Osmanabadi and Salem goats have excellent capability to adapt to harsh conditions [ 15 ]. In Bedouin goats that have extreme resilience to severe water deprivation, aldosterone concentration along with rennin activity increased during dehydration conditions [ 19 ].…”

“…Water restriction elicits changes in a number of physiological and behavioral characteristics in animals [ 3 , 5 ]. Water deprivation beyond normal physiological limits first alters hormonal dynamics, such as the renin–angiotensin–aldosterone system, by increasing aldosterone and vasopressin concentrations to reabsorb water and electrolytes for the maintenance of osmotic balance in plasma and intracellular spaces [ 15 , 16 , 17 ]. These responses prevent cell damage, decrease thyroid hormone secretion to reduce energy metabolism and respiratory water loss in thermoneutral conditions, and increase cortisol concentrations to regulate protein, fat, and glucose metabolism [ 15 , 16 , 17 , 18 , 19 ].…”

“…Water deprivation beyond normal physiological limits first alters hormonal dynamics, such as the renin–angiotensin–aldosterone system, by increasing aldosterone and vasopressin concentrations to reabsorb water and electrolytes for the maintenance of osmotic balance in plasma and intracellular spaces [ 15 , 16 , 17 ]. These responses prevent cell damage, decrease thyroid hormone secretion to reduce energy metabolism and respiratory water loss in thermoneutral conditions, and increase cortisol concentrations to regulate protein, fat, and glucose metabolism [ 15 , 16 , 17 , 18 , 19 ]. When hormonal changes cannot regulate body water balance, further changes associated with water deprivation can occur, such as decreased plasma and total body water volume, greater hemoconcentration, increased concentrations of plasma metabolites, electrolytes, and kidney excretory products, and reduced feed intake and energy metabolism [ 7 , 8 , 9 , 20 , 21 , 22 , 23 ].…”

“…The capacity of livestock to regulate body water balance and metabolic activity varies among breeds [ 19 , 25 ]. Many small ruminant breeds in extreme environments have excellent resilience to water restriction compared with others in different regions of the world [ 2 , 6 , 15 , 19 , 25 ].…”

Comparative diurnal and seasonal variations of ACTH, cortisol and aldosterone in Ouled Djellal and D’Man sheep breeds reared in arid lands

“…Still, due to the availability of water ad libitum, the response of the renin-angiotensin system is not accompanied by a high plasma concentration of aldosterone. Indeed, Aleena et al (2020) reported that under heat stress, the level of plasma aldosterone was significantly lower in Malabari goats, which had ad libitum access to water. However, in our study, the highest aldosterone concentration coincides with the autumn and spring equinoxes and not with periods of high temperature.…”