Efeito da adição de butirato de sódio encapsulado e arginina em dietas para frangos de corte submetidos a um modelo de desafio entérico e térmico

Abstract

The objective of this work was to supplement commercial broiler diets with microencapsulated sodium butyrate (BSE) and arginine (Arg) on productive performance, bone quality and integrity, skin and intestine resistance and elasticity, intestinal mucosa morphometry and blood parameters of broilers developing the two challenge models. Two experiments were carried out, the first from 1 to 22 days of age, in which the birds were submitted or not to an enteric challenge model and a second experiment, from 1 to 35 days of age, in which the birds were submitted or not to a thermal challenge model. A total of 768 male broiler chicks were used, randomly distributed in a completely randomized design in a 4 x 2 factorial scheme (4 diets vs with and without experimental challenge), in the first experiment, as diets used were: Arginine: Lysine 1:13; Arginine: Lysine 1:13 + butyrate; Arginine: Lysine 1:30 and Arginine: Lysine 1:30 + butyrate and no second experiment in a 2x2x2 factorial arrangement, being without and with arginine (1:13 and 1:30), without and with encapsulated sodium butyrate (0 and 1kg / ton) and without and with thermal challenge, obtaining 8 treatments and 6 repetitions each, totaling 48 experimental units, with 16 birds each. For the first experiment, the results presented that in the period from 1 to 14 and 1 to 21 days as birds greater weight gain and feed consumption when they received the association of Arg + BSE, respectively. The bone measures of the tibias presented greater (P<0.05) thickness and weight for the birds that received the BSE supplementation. The challenged birds, regardless of diet, resulted in smaller (P<0.05) tibia diameter. For broilers subjected to heat stress, the results show that in the first week of age of the birds the diet without Arg and the challenged birds had higher (P<0.05) feed intake. In the performance from 8 to 14 days, the treatment containing sodium butyrate showed greater weight gain (P<0.05) while the challenged birds had the opposite effect. In the splitting of the triple interaction from 28 to 35 days for feed conversion, live weight and weight gain, the birds in the control group and those that received the supplementation of sodium butyrate and arginine showed better results. There was an interaction (P<0.05) for bone measurements at 14 days of age between the addition of BSE and the experimental challenge for tibial weight and Seedor index. When unfolding the interaction, the birds in the control group and those that received BSE supplementation showed better results. Birds receiving sodium butyrate had better (p>0.05) skin elasticity at 35 days of age. For morphometry, the challenged birds showed greater crypt depth and shorter villi length and width. Challenged birds had lower (p<0.05) drip loss. The birds in the control group resulted in a higher pH (p<0.05) when compared to the birds in the challenged group. It is concluded that the tested enteric challenge did not change the productive performance, however, it affected the morphometry of the ileum mucosa. In the first experiment, Arg and BSE supplementation was effective in improving performance in the from 1 to 14 days of age and BSE improved bone measurements. In the second experiment, the association of BSE and Arg, even in a situation of thermal challenge, showed positive effects on performance in the last week of the experiment.