Effect of different sources and inclusion levels of dietary fat on productive performance and egg quality in laying hens raised under hot environmental conditions

Abstract

Objective This experiment aimed to investigate the effect of different sources and inclusion levels of dietary fat on productive performance and egg quality in laying hens raised under hot environmental conditions. Methods A total of 480 Hy-Line Brown laying hens at 31 wk of age were randomly allotted to 1 of 5 experimental diets. The control diet contained 2,800 kcal/kg nitrogen-corrected apparent metabolizable energy with no fat addition. Four additional diets were prepared by adding 2.0% or 4.0% of animal fat (AF) or soybean oil (SO). Energy and nutrient concentrations were consistent among all diets. Diets were fed to hens for 4 weeks. Average daily room temperature and humidity were 26.7°C±1.52°C and 77.4%±4.50%. The heat stress index was approximately 76, indicating that hens were raised under heat stress conditions. Results Final body weight (BW) was greater (p<0.05) for hens fed diets containing 2.0% or 4.0% AF than for those fed the control diet or diets containing 2.0% or 4.0% SO. The BW gain and feed intake were greater (p<0.05) for hens fed diets containing additional AF or SO than those fed the control diet. Eggshell thickness was the greatest (p<0.05) for hens fed the control diet, but the least (p<0.05) for hens fed diets containing 4.0% SO. Egg yolk color was the greatest (p<0.05) for hens fed the control diet, but the least (p<0.05) for hens fed diets containing 4.0% SO. Conclusion Inclusion of supplemental fat (AF and SO) in diets exhibits preventative effects on BW loss for hens raised under hot environmental conditions when energy and nutrient concentrations in diets were maintained. The effects were greater for AF than for SO. However, inclusion of supplemental fat in diets decreases eggshell thickness and egg yolk yellowness, possibly due to a reduction in Ca absorption and intake of egg yolk colorants.

Response of broilers to supplementation of branched-chain amino acids blends with different valine contents in the starter period under summer conditions

“…The daily BWG (58.4 g) and FCR (1.84) of the N birds were quite below the standard (65.8 g and 1.68, respectively) expected for mixed-sex broilers under controlled environment conditions [ 15 ]. This might be since the heat exposure impairs the intestinal morphology, appetite and consequently performance traits [ 9 – 11 , 20 ] because the present study was conducted under warm summer conditions (average weekly indoor 32.8°C±1.7°C temperature and 61.1%±4.12% humidity). In agreement with Liu et al [ 21 ], our study revealed that the impact of heat stress could be mitigated partially by adjusting PCs of the diets as a nutritional practice.…”

Comparative effects of dietary functional nutrients on growth performance, meat quality, immune responses, and stress biomarkers in broiler chickens raised under heat stress conditions

“…In addition, recent intensive breeding strategies realize the very high performance of poultry, whereas it concomitantly causes increased heat production, which lowers the ability of thermoregulation of poultry [2]. Poultry exposed to heat stress is well-known to experience various physiological and behavioral abnormalities, which markedly decrease productive performance, health, and welfare of poultry [3][4][5][6]. Thus, the development of effective strategies to decrease the heat stress of poultry is essential for the current and future poultry industry.…”

“…4) PC, basal diet; NC, basal diet; Gln, basal diet + 0.5% glutamine; Cr picolinate, basal diet + 500 ppb chromium picolinate; Vit C, basal diet + 250 mg/kg vitamin C; Bet, basal diet + 0.2% betaine; Tau, basal diet + 1.0% taurine.…”

Assessment of growth, performance, and end-product value when high oleic soybean oil is fed to market hogs, broiler chickens and laying hens

“…Eggs from hens supplemented with either four percent animal fat or four percent soybean oil, saw a decrease in egg yolk yellowness compared to eggs from hens supplemented with no added fat, two percent animal fat, or two percent soybean oil (Kim et al, 2019). Celebi and Macit found no differences in egg quality parameters from hens supplemented with tallow, sunflower oil, or flaxseed oil (Celebi and Macit, 2008).…”

“…Consideration should be placed on the effects that occur to hen performance. Hens fed animal fat or soybean oil had greater body weight gain compared to hens fed a control no added fat diet combined, interestingly, with increased feed intake (Kim et al, 2019). On contrary, Celebi and Macit saw reduced feed intake and improved feed conversion ratio when fed diets containing two percent tallow, one percent tallow + one percent flaxseed oil, two percent sunflower oil, or two percent flaxseed oil (Celebi and Macit, 2008).…”