Aspersão de Lactiplantibacillus plantarum durante a incubação de ovos e uso de butirato de sódio na dieta de frangos de corte

Abstract

The objective of this study was to evaluate the effects of spraying a solution containing Lactiplantibacillus plantarum onto eggs during incubation, combined with dietary sodium butyrate supplementation, on performance, carcass traits, and intestinal and bursa of Fabricius histology in broiler chickens from 1 to 35 days of age. A total of 576 fertile Ross 708 eggs from 32-week-old breeders were assigned to two groups: spraying with sterile phosphate solution or L. plantarum (10⁹ CFU/mL) diluted in sterile phosphate solution. Solutions were individually sprayed onto the eggs on days 1, 3, 7, 10, 14, and 18 of incubation. After hatch, birds received diets with or without sodium butyrate (1.0 kg/t from 0 to 8 days and 0.5 kg/t thereafter until 35 days). The experimental design was completely randomized in a 2 × 2 factorial arrangement, with six replicates of 10 birds. Spraying L. plantarum increased body weight gain at 21 (P=0.01) and 35 days (P=0.05), whereas butyrate reduced body weight gain at 21 days (P<0.01), with no effect at 35 days. An interaction (P<0.05) between spraying and butyrate was observed for feed intake and feed conversion ratio at 21 and 35 days. In birds from sprayed eggs, butyrate increased feed intake (P=0.01) and worsened feed conversion ratio (P=0.02) at 21 days, with no effects at 35 days. In birds from non-sprayed eggs, butyrate reduced feed intake at 21 and 35 days (P=0.01) and improved feed conversion ratio at 35 days (P=0.05). In males, spraying increased carcass yield (P=0.05) and reduced relative liver and bursa weights (P=0.05), whereas butyrate reduced carcass yield (P=0.01), reduced relative liver weight, and increased breast, thigh, and drumstick yields (P<0.01). In females, butyrate reduced carcass yield and relative spleen and liver weights (P<0.05), while increasing breast, thigh, and drumstick yields (P<0.01); spraying reduced the relative viscera weight (P<0.01). An interaction was observed for thigh yield and relative bursa weight (P<0.05). Butyrate reduced the duodenal villus-to-crypt ratio (P<0.05), with no effects on jejunal or ileal histomorphometry. Bursa follicular area was unaffected, but an interaction was observed for medullary area percentage (P<0.01), with a higher percentage in birds from sprayed eggs receiving butyrate. In conclusion, the combination of L. plantarum spraying and dietary sodium butyrate did not provide a consistent productive advantage over the individual strategies. Spraying primarily favored performance, whereas butyrate showed more evident effects on commercial cut yields.