Ideal proportion of roughage and concentrate for Malpura ewes to adapt and reproduce in a semi-arid tropical environment

The study was designed to identify the most appropriate roughage to concentrate ratio for Malpura ewes under semi-arid tropical environments. The study was conducted for a period of 35 days and included 30 (2 years old) non-pregnant Malpura ewes weighing between 30 and 35 kg. Estrus synchronization was carried out in all the animals using indigenously developed intravaginal sponges impregnated with progesterone. The ewes were randomly divided into three groups (n = 10/group) namely R50 (n = 10; roughage to concentrate, 50:50), R60 (n = 10; roughage to concentrate, 60:40), and R70 (n = 10; roughage to concentrate, 70:30). Individual feed and water intake was recorded on a daily basis throughout the course of the study. Growth variables, physiological responses, blood metabolites, and endocrine responses were estimated at weekly intervals. Results of the study indicated that nutritional treatment significantly influenced growth variables including body weight (p < 0.01), BCS (p < 0.01), feed intake (p < 0.05), and water intake (p < 0.01) among the different treatment groups. The highest growth variables were recorded in R50 whereas the lowest were in R70. Both respiration rate (p < 0.01) and plasma estradiol levels (p < 0.05) also showed a similar trend as that of the growth variables. However, growth hormone (p < 0.01), T-3 (p < 0.01), Hb (p < 0.01), glucose (p < 0.05), and estrus duration (p < 0.05) demonstrated a reverse trend with highest values recorded in R70 and lowest in R50. However, the nutritional treatment did not influence pulse rate, rectal temperature, T-4, progesterone, PCV, total cholesterol, total protein, albumin, estrus%, and estrus cycle length. Since the additional concentrate supplementation in R50 and R60 did not improve the production variables, it can be concluded that providing 70 % roughage and 30 % concentrate could be a more appropriate and economically feasible ration composition for Malpura ewes reared in semi-arid tropical environments.