Among domestic ruminants, goats are renowned for their ability to tolerate water deprivation, water restriction and energy restriction. However, some basic questions regarding their ability to endure water restriction under heat stress are still open. Three levels of water restriction (56%, 73% and 87% of the ad libitum) were imposed on 20 cross-bred 3-year-old female goats (75% German Fawn and 25% Hair Goat) distributed into four groups, with five animals per treatment. The experiment was conducted from the beginning of July to the end of August in a farm located in the Eastern Mediterranean region of Turkey (40 m in altitude; 36 59' N, 35 18'E), in which subtropical weather conditions prevail. The average daily temperature during the experiment was 34.2°C, whereas the highest and lowest temperatures were 42°C and 23.1°C, respectively. The average relative humidity was 68.2% and wind speed was 1.2 km/h. Weekly average thermal heat indexes during the experiment were 78.3 (week 1), 79.1 (week 2), 80.1 (weak 3), 79.8 (weak 4), 81.3 (weak 5) and on average 79.7. Feed intake, heart rate, thermoregulatory responses (rectal temperature, respiration rate), blood plasma concentrations of ions (Na, K), antidiuretic hormone (ADH), metabolites (glucose, cholesterol, creatinine and urea) and behavioral aspects (standing, walking, lying) were studied over 30 days. The responses to water restriction were proportional to the level of restriction. The reductions in feed intake (up to 13%), BW (up to 4.6%) and the increases in rectal temperature (0.5°C) and breath rate (10 respirations/min) were moderate and also were far from responses encountered under severe heat and water stresses. The increase in plasma Na (from 119 to 140 mM) and ADH concentrations (from 12.6 to 17.4 pg/ml) indicates that the physiological response to water restriction was in response to mild dehydration, which also explains the increase in blood plasma concentrations of glucose, cholesterol, creatinine and urea. Behavioral responses (reduction in walking from 226 to 209 min/day and increase in lying from 417 to 457 min/day) were associated with conservation of energy or thermoregulation (reducing the exposure to direct radiation).Keywords: water restriction, heat stress, physiological response, adaptation, resilience ImplicationsThe goats used in the present study (a mix of 75% temperate breed with 25% local adapted breed) have shown remarkable capacity to endure significant water restriction for a long time. Water restriction endurance was associated with minimal disruption of plasma electrolyte and metabolite composition, thermoregulation and general well-being. The water-saving responses were activated in response to mild loss of body fluids and increase in plasma sodium concentration and ADH concentration. The results of this study help us understand the adaptation of goats to water restrictions and might be helpful for management purposes under conditions of water limitation, or as a technique to manipulate feed intake.

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This study was conducted to determine the effects of hempseed (H) on performance, carcass traits, and antioxidant activity in Japanese quail (Coturnix coturnix japonica). A total of 192 quail with seven-days old were divided into four experimental groups with four replicates. The treatments were; i) Control diet (C, no hempseed); ii) 5% hempseed in diet (H5); iii) 10% hempseed in diet (H10); and iv) 20% hempseed in diet (H20). The body weight (BW) and feed intake (FI) of quail was determined at 7, 21 and 42 d of age. At 42 d of age four quail were slaughtered and the carcass and internal organ traits were determined. Malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), nitric oxide (NO) and total protein were determined in the blood serum end of the experiment. The BW of the groups were not significant at 7 and 21 d, however in the 20% hempseed group BW decreased at 42 d (p<0.05). The FI and feed conversion ratio were not significant among the treatment groups. The carcass, liver, intestine and heart weight and their percentage to carcass were significantly differ in treatment groups (p<0.05). The serum MDA and NO decreased in hempseed addition (p <0.001). The serum SOD, CAT and GSH-Px were increased by hempseed supplementation (p<0.001). In conclusion, hempseed supplementation to quail diets may not improve quail performance traits but increase antioxidant activity in blood.

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This study was conducted to identify gene polymorphisms and to investigate the relationships of polymorphisms with yield and composition of milk from Holstein cows. Significant relationships of growth hormone (GH), leptin (LEP) and myogenic factor 5 (MYF5) gene polymorphisms with 305‐day milk yield were observed (P < 0.01). Signal transducers and activators of transcription 5A (STAT5A) gene polymorphism did not show any significant relationships with investigated traits (P > 0.05). With regard to the 305‐day milk yield, GH‐LV, LEP‐AA and AB and MYF5‐GG genotypes were found to be superior over the other genotypes. It was concluded based on present findings that GH, LEP and MYF5 genes could be used as candidate genes for milk yield of Holstein cows.