Utilização de vitamina D para suínos e perspectivas de uso nas diferentes fases de produção

Abstract

This thesis work was carried out to investigate vitamin D supplementation for sows. In this sense, a literature review on the subject was carried out, a systematic review with the survey of articles that evaluated vitamin D supplementation in pigs and an experiment with the use of vitamin D for sows. Vitamin D is part of the class of fat-soluble vitamins and can be supplied via the diet usually in its inactive forms, including vitamin D2, D3, or 25(OH)D3, forms that are activated by two hydroxylation steps that occur in the liver and blood vessels. kidneys. Vitamin D3 plays a role in several crucial processes in animal metabolism. It influences the composition of the intestinal microbiota, being able to mitigate intestinal damage and protect against the induced inflammatory state of challenged piglets; it can alter the proliferation of muscle-derived myoblasts, improving skeletal muscle development in the swine fetus; and is capable of inducing gene expression of the antimicrobial peptide cathelicidin, capable of fighting bacterial and viral infections. Therefore, it is understood that vitamin D concentrations greater than 45μg/kg can meet a need that goes beyond the common routes of vitamin D. The search was carried out in the Scopus, Web of Science and PubMed databases through the CAPES Portal de Periódicos collection. The resulting articles were exported to a reference management program and submitted to several selection criteria, which started from a total of 1997 articles and were filtered until reaching 57 articles. Studies were classified by year of publication, with 67.1% of searches found between 2010 and 2020. The United States represented the country with the highest number of publications (31 articles). The most used source of vitamin D was D3, followed by 25(OH)D3 with 38.6 and 17.1% respectively. The most studied rearing phase was piglets in the nursery, where 25(OH)D3 was the most present source of vitamin D. Most of the studies occur mainly in critical periods, when the demand for vitamin D may be higher; the intensification of the use of 25(OH)D3 as a more efficient source in these periods demonstrates the relevance of vitamin D in swine nutrition. The systematic review can present an overview of studies, exploring which phases were most investigated and which sources were most explored in the articles, leaving the possibility of new scientific research, serving as a starting point for studies that want to observe results that have not yet been explored. The objective of the experiment (chapter 3) was to evaluate the supplementation of high levels of 25(OH)D3 in matrices and reflex in the progeny. For this, a total of 250 primiparous and multiparous sows with an average body weight of 204.78 kg were used, arranged in five treatments with ten repetitions. All experimental diets contained a baseline amount of vitamin D3 (45μg/kg of D3) and the experimental treatments consisted of adding 25(OH)D3 at five increasing levels (0μg/kg 25(OH)D3; 25μg/kg 25(OH)D3; 50μg/kg 25(OH)D3; 75μg/kg 25(OH)D3 and 100μg/kg 25(OH)D3. The productive performance of the sows were evaluated, as well as the reflection of the maternal diet on the productive performance of the litters, the serum levels of vitamin D metabolites in the sows and piglets, serum immunoglobulins A, G and M of the sows and the fatty acid profile of the milk and colostrum. 25(OH)D3 supplementation improved the sow's vitamin D status after parturition and immunoglobulin levels at parturition and weaning. The performance of the sows was not affected, however, the development of the piglets was influenced by vitamin D supplementation in the mother's diet. The profile of fatty acids in milk can be indicative of an effect on the outcome in piglets and should be further investigated.