Effect of fibrous diet and vitamin C inclusion on uniformity, carcass traits, skeletal strength, and behavior of broiler breeder pullets.

This experiment studied the effect of broiler breeder nutritional strategies on uniformity, carcass traits, tibia parameters, and behavior during rearing and prebreeder periods (up to 22 wk of age). One-day-old pullets (n = 384) were randomly assigned to 4 treatments arranged as a 2 × 2 factorial, with 2 fiber levels (control vs. fibrous diet, 15% diluted in AMEn and nutrient content) and 2 vitamin C feed inclusions (0 vs. 200 mg/kg). At 6, 15, and 22 wk, blood sampling was carried out (4 birds/replicate) to determine serum alkaline phosphatase (ALP) levels, and behavior was observed by visual scan sampling. At 22 wk, carcass traits, tibia parameters, and intestinal morphology were assessed (2 birds/replicate), and tail- and wing-feather integrity of all birds were scored. Fibrous diet did not modify BW uniformity, mortality, or tibia growth when compared with control diet. Pullets fed the fibrous diet had lower tibia breaking strength, elastic modulus, and ash content values (P < 0.05). They also had lower ALP serum level at 6 and 22 wk (P < 0.05), their breast muscle was less developed (18.5 vs. 19.8%, P < 0.05), and their abdominal fat deposition was higher (1.14 vs. 0.87%, P < 0.05). At 15 and 22 wk, they performed, on average, 97% less grasping feather pecking and 45% less non-food object pecking behaviors, and their wing-feather score was lower (P < 0.05) at 22 wk. Tail- and wing-feather scores of the control treatments were reduced by vitamin C inclusion (tail: 0.30 vs. 1.15, P < 0.05; wing: 0.98 vs. 1.26, P < 0.05) at 22 wk. In conclusion, fibrous diet improves carcass traits (reduces breast muscle and increases abdominal fat deposition), deteriorates bone mineral deposition and thus skeletal strength, and reduces stereotypic behaviors, improving wing-feather integrity. Vitamin C inclusion improves tail- and wing-feather integrity of lower in feed allowance.

Effect of medium- and long-chain triglyceride supplementation on small newborn-pig survival.

The pre-weaning survival of 508 piglets was studied with a categorical survival analysis, evaluating the effect of medium-long-chain triglyceride (MCT-LCT) supplementation on small newborn pigs, and determining additional risk factors. Half of the 98 piglets born with birth weight (BW)<1250 g received 1.95 g of MCT-LCT each 24 h during the first 3 days of life, and their death hazard was reduced 1.9-fold in relation with small unsupplemented siblings. The death hazard ratio (HR) of supplemented animals compared to 410 heavier littermates was not different. However, the HR for newborn pigs that were small in relation with their siblings was 2.8, and the HR for litters with >12 piglets born alive was 4.5. There was variation across months, and also piglets from primiparous sows had increased hazard of death (HR=4.0).