Effects of vitamin A on growth performance and tissue retinol of starter White Pekin ducks

Performance and bone characteristics of broilers fed diets supplemented with vitamin A at different concentrations

This work evaluated the influence of vitamin A on performance, organ weight, and bone and skin characteristics in broilers (Cobb 500) at 21 and 42 days of age. A total of 1920 chickens were distributed in a randomised design, considering six vitamin A supplementation levels (0, 6000, 16,000, 26,000, 36,000, and 46,000 IU kg-1 ), with 16 replicates and 20 chickens per experimental unit, established due to rising the range of vitamin levels observed in the literature to evaluate the effect of vitamin A on broilers. At 22 days, half of the replicates from each treatment continued receiving the initial diet, and the other eight repetitions received diets without vitamin A (0 IU kg-1 ) until 42 days. The level of vitamin A influenced feed intake (FI) and body weight gain (BWG) until 21 days for all treatments. Broilers at 21 days of age had a more significant BWG at a vitamin A supplementation level of 28,209 IU kg-1 . At 42 days, vitamin A influenced the BWG and FI of broilers at treatments that were not supplemented after 21 days. Treatments supplemented up to 42 days showed quadratic responses to vitamin A for BWG, FI, and feed conversion. The vitamin A levels influenced the relative weights of the small intestine, pancreas, gizzard, abdominal fat, Seedor index, and breaking strength at 42 days, where the adequate supplementation of vitamin A improved these characteristics in broilers. Vitamin A supplementation from 22 to 42 days old did not affect broiler performance. An increased BWG was obtained when vitamin A supplementation occurred until 42 days, with supplementation of 29,375 IU kg-1 and a lower response of feed conversion with the addition of 27,775 IU kg-1 .

Pros and Cons of Dietary Vitamin A and Its Precursors in Poultry Health and Production: A Comprehensive Review

Vitamin A is a fat-soluble vitamin that cannot be synthesized in the body and must be obtained through diet. Despite being one of the earliest vitamins identified, a complete range of biological actions is still unknown. Carotenoids are a category of roughly 600 chemicals that are structurally related to vitamin A. Vitamin A can be present in the body in the form of retinol, retinal, and retinoic acid. Vitamins are required in minute amounts, yet they are critical for health, maintenance, and performing key biological functions in the body, such as growth, embryo development, epithelial cell differentiation, and immune function. Vitamin A deficiency induces a variety of problems, including lack of appetite, decreased development and immunity, and susceptibility to many diseases. Dietary preformed vitamin A, provitamin A, and several classes of carotenoids can be used to meet vitamin A requirements. The aim of this review is to compile the available scientific literature regarding the sources and important functions, such as growth, immunity, antioxidant, and other biological activities of vitamin A in poultry.

Non-targeted metabonomics to investigate the differences in the properties of ginseng and American ginseng based on rapid resolution liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry

The basic properties of herbal medicines are cold, hot, warm, and cool. The differentiation of these properties is important for the diagnosis and treatment of diseases. Ginseng and American ginseng possess opposite properties of warm and cool, respectively. At present, the mechanisms and the influence of steaming leading to the differences in their properties are not clear and require further investigation. Therefore, nontargeted metabonomics based on liquid chromatography-mass spectrometry was applied to investigate the effects of ginseng, American ginseng, and their variants on the changes in endogenous metabolites in rat urine. A total of 19 potential biomarkers were screened out and identified, of which 17, 7, and 5, were respectively related to warm, cool, and both warm and cool properties with opposite effects. The metabolic pathways corresponded to fatty acids, lipids, glycolysis, and energy metabolisms. The warm and tonic effects of red ginseng are stronger than those of ginseng and consistent with the theory of traditional Chinese medicine. The red American ginseng has cool property; however, the degree of coolness is less than that of American ginseng. This study provides a reference methodology to understand the effects of processing and mechanisms associated with the differences in the properties of herbal medicines.