The effect of the concentration and feeding duration of spray-dried plasma protein on growth performance, digestive enzyme activities, nutrient digestibility and intestinal mucosal development of broiler chickens

Abstract

This study was undertaken to investigate the effect of the supplementation level and feeding duration of spray-dried porcine plasma (SDPP) on performance and digestive physiology of broiler chickens. Three inclusion levels of SDPP (0, 10 or 20 g/kg) were used in lieu of meat meal and fed from hatch to 5 or 10 days of age. At Day 10, there was an interaction (P < 0.05) between the inclusion level and feeding duration of SDPP, improving bodyweight (BW) in birds that received SDPP at the highest concentration over the longer feeding duration. Inclusion of SDPP resulted in lower (P < 0.01) feed intake, higher (P < 0.01) BW and improved (P < 0.05) feed conversion ratio (FCR). Furthermore, FCR was improved (P < 0.001) in birds that were offered SDPP over the longer feeding duration than in those that received SDPP for a shorter duration. The pancreas was heavier (P < 0.05) in the birds that received SDPP at the highest concentration over the long feeding duration. At 24 days of age, there was an interaction (P < 0.05) between the inclusion level and feeding duration of SDPP, indicating the lowest amino acid, protein, gross energy and dry matter digestibility in the birds that received SDPP at the highest concentration over the longer feeding duration. Villus height was increased (P < 0.001) by the experimental factors and their interaction, revealing longer villi in the birds that received SDPP at the low level over the short feeding duration. Apparent villus surface area was higher (P < 0.001) in birds that were offered diets that contained the highest concentration of SDPP. There was an interaction (P < 0.01) between experimental factors with regards to the apparent villus surface area. Up to Day 35, the level of SDPP tended to increase (P = 0.06) BW. Level (P < 0.001) and feeding duration (P < 0.01) improved FCR in the birds that received SDPP for the long feeding duration. It would be more economical to use a low inclusion level of SDPP over a longer period of time to achieve the same benefits.