Laying performance, digestibility and plasma hormones in laying hens exposed to chronic heat stress as affected by betaine, vitamin C, and/or vitamin E supplementation

Abstract

Heat stress had a negative effect on laying hens’ performance, thus this research was to study the influences of betaine (Bet, 1000 mg/kg betaine), vitamin C (VC, 200 mg/kg ascorbic acid), and vitamin E (VE, 150 mg/kg α-Tocopherol acetate) and their possible combinations on egg production, digestibility of nutrients, plasma hormones and reproductive organs of dual-purpose hens exposed to chronic heat stress. Two hundred and eighty eight hens and thirty-six cocks from 32 to 48 weeks of age were divided into nine treatment groups of four replicates, each containing eight hens and one cock. One group was kept under thermo-natural condition and the eight others were kept under chronic heat stress (CHS). One of these eight was used as a negative control, while the others were supplemented with VC, VE and/or betaine and their possible combinations. Body weights, laying rate, feed intake, and feed conversion ratio in hens reared under CHS rooster without any supplementation during 32 to 48 weeks of impairment (P = 0.0052) were recorded. Hens reared under heat stress and fed a diet supplemented with either Bet, VC, VE or combination of the supplements increased production traits. However, hens supplemented with VC showed the greatest production traits. Plasma glucose, estradiol-17 (E2), progesterone (P4), tri-iodothyronine (T3) and thyroxine (T4) decreased in hens reared under CHS and fed a diet with no supplementation compared to the other treatments (P = 0.001). Liver weights, spleen weights, thyroid gland weights, ovary weights, oviduct weights and oviduct lengths were lowest in hens reared under CHS and fed a diet with no supplementation (P = 0.0480). In conclusion, dual purpose hens reared under CHS and supplemented with VC at 200 mg/kg diet and Bet at 1000 mg/kg enhanced the laying performance and combated CHS.

Effect of resveratrol on growth performance, rectal temperature and serum parameters of yellow‐feather broilers under heat stress

“…In this study, supplementation with resveratrol showed an increasing trend on the GLU and TP content, while TC, TG, and UA contents in serum were decreased, especially supplementation with resveratrol 500 mg/kg. Decreased serum GLU and TP are known to be a limiting factor for animal growth (Attia et al., ), and that was consistent with what we observed in our data of lower growth performance, but the gap was narrowed down by resveratrol supplementation. Liu et al.…”

“…Besides these meta- (Luo et al, 2018). Attia et al (2016) also found that heat stress significantly decreased serum GLU content of laying hens.…”

“…Attia et al. () also found that heat stress significantly decreased serum GLU content of laying hens. However, Xie et al.…”

Effects of vitamin E supplementation on performance, serum biochemical parameters and fatty acid composition of egg yolk in laying hens fed a diet containing ageing corn

“…The earlier studies are inconclusive with regard to the correlation between the VE and laying performance. An increase in the VE content of hen diets from 20–25 IU/kg to 60–65 IU/kg significantly improved daily egg production (Kirunda, Scheideler, & Mckee, ), while even high dietary concentrations of VE (100 and 200 IU/kg) did not increase egg production, as compared with non‐supplemented diets and diets supplemented with a low (20 IU/kg) amount of VE (Attia et al, ; Mohiti‐Asli, Shariatmadari, & Lotfollahian, ). In the present study, VE did not significantly improved egg production performance.…”

Effects of Dietary Protein Level and Betaine Supplementation on Nutrient Digestibility and Performance of Japanese Quails

“…Similarly, dietary betaine supplementation was also shown to improve the digestibility of CP (Ezzat et al, 2011;Attia et al, 2016) and EE in laying chickens (Ezzat et al, 2011). Moreover, studies with broilers have revealed that betaine improved DM (Ratriyanto et al, 2014a;Amerah & Ravindran, 2015), OM (El-Husseiny et al, 2007), CP,…”