Effect of Dietary Vitamin A on Reproductive Performance and Immune Response of Broiler Breeders

Abstract

The effects of dietary vitamin A supplementation on reproductive performance, liver function, fat-soluble vitamin retention, and immune response were studied in laying broiler breeders. In the first phase of the experiment, 1,120 Ross-308 broiler breeder hens were fed a diet of corn and soybean meal supplemented with 5,000 to 35,000 IU/kg vitamin A (retinyl acetate) for 20 weeks. In the second phase, 384 Ross-308 broiler breeder hens were fed the same diet supplemented with 5,000 to 135,000 IU/kg vitamin A (retinyl acetate) for 24 weeks. The hens' reproductive performance, the concentrations of vitamins A and E in liver and egg yolk, liver function, mRNA expression of vitamin D receptor in duodenal mucosa, antibody titers against Newcastle disease virus vaccine, and T-cell proliferation responses were evaluated. Supplementation of vitamin A at levels up to and including 35,000 IU/kg did not affect reproductive performance and quadratically affected antibody titer to Newcastle disease virus vaccine (p<0.05). Dietary addition of vitamin A linearly increased vitamin A concentration in liver and yolk and linearly decreased α-, γ-, and total tocopherol concentration in yolk (p<0.01) and α-tocopherol in liver (p<0.05). Supplementation of vitamin A at doses of 45,000 IU/kg and above significantly decreased egg weight, yolk color, eggshell thickness and strength, and reproductive performance. Dietary vitamin A significantly increased mRNA expression of vitamin D receptor in duodenal mucosa (p<0.05), increased aspartate amino transferase activity, and decreased total bilirubin concentration in serum. Supplementation of vitamin A at 135,000 IU/kg decreased the proliferation of peripheral blood lymphocytes (p<0.05). Therefore, the maximum tolerable dose of vitamin A for broiler breeders appears to be 35,000 IU/kg, as excessive supplementation has been shown to impair liver function, reproductive performance, and immune response.

Effects of vitamin A supplementation in the diet of breeding geese on offspring intestinal tissue morphology and immune performance

“…Vitamins can act on offspring through eggs, so we studied the effect of dietary vitamin A (VA) supplementation in maternal and their offspring on the intestinal tissue morphology and immune performance of goslings.VA can change the intestinal morphology and structure of animals [1]. VA can improve fecundity [2] and can promote the formation of sex hormones to maintain normal bone growth and development [3][4][5]. VA can also regulate the metabolism of fat, carbohydrates and proteins, promote growth, and play important roles in immune function and nonspecific responses to disease [6,7].…”

Effects of Plantago major extract on serum levels of antioxidant vitamins and minerals in broiler

“…Vitamin A and vitamin E are essential micronutrients throughout the life cycle and have many effects with antioxidant activities, recommended for chickens (NRC, 1994;Yuan et al, 2014). But, in this study, we can say that using P. major extract have no effect on serum vitamin A and E levels.…”

Impact of Dietary Supra-Nutritional Levels of Vitamins A and E on Fertility Traits of Broiler Breeder Hens in Late Production Phase

“…This trial described the effect of a nine weeks period of dietary supplementation with supra-nutritional levels of vitamin A and E in broiler breeders during the late production cycle, when fertility traits tend to decline. Both vitamins A and E are considered important factors related to the maintenance of fertility in mammals as well as in birds [11,23,32,33]. At the beginning of the experiment, hens in all groups showed similar laying ability even though the number of produced eggs was smaller than those proposed by Aviagen [34] for performance objectives of Ross-308 breeders (≤2 eggs/bird/week for the majority of the experimental groups vs. 3.60 eggs/bird/week for birds aged of 61 weeks).…”

“…Conversely to a previous study showing that dietary supplementation of laying hens with levels of vitamin A above the National Research Council [36] recommendations had no effect on egg production [37,38], our study showed that it was possible to maintain or improve the egg production of hens under standard rearing conditions. Moreover, Yuan et al [23] failed to find any beneficial effect in using high levels of vitamin A in diet on the reproductive performance of broiler breeder hens. However, it is worth remembering that the mentioned previous studies used longer periods of supplementation covering the entire laying period, whilst in the current study were used hens at the end of the production phase.…”

“…Nevertheless, the nutritional requirement for vitamins proposed for commercial flocks may not support the actual needs of broiler breeders. Moreover, the improvement of genetic, management and environment of breeder flocks lead to changes in breeders vitamins requirements [19], which draw the attention of researchers into the role of vitamins on the reproductive performance of broiler breeders [13,[20][21][22][23][24][25][26][27][28]. However, additional research on some vitamins may contribute to clarify the optimum vitamin allowance needed for particular strains of parent stock or to maintain a high production level.…”