Amino acid and calcium digestibility in hatchery byproducts fed to nursery pigs

Abstract

The objective of this study was to determine amino acid (AA) and calcium (Ca) digestibility of hatchery byproducts in nursery pigs. In experiment 1, the coefficients of standardized ileal digestibility (CSID) of AA in hatchery byproducts were measured using 10 barrows surgically fitted with T-cannulas at the distal ileum (initial body weight = 11.3 ± 1.3 kg). Four diets were prepared to contain 30 % of infertile eggs, unhatched eggs, culled chicks, and a mixture (20 % dried infertile eggs + 20 % dried unhatched eggs + 60 % dried culled chicks) as the sole source of nitrogen and a nitrogen-free diet was additionally prepared to measure basal endogenous losses of AA. In experiment 2, ten nursery barrows (initial body weight = 10.2 ± 0.7 kg) were used to measure the coefficient of standardized total tract digestibility (CSTTD) of Ca in hatchery byproducts. Four experimental diets contained 10, 10, 25, and 15 % of infertile eggs, unhatched eggs, culled chicks, and the mixture (20 % dried infertile eggs + 20 % dried unhatched eggs + 60 % dried culled chicks) as the sole source of Ca, respectively and a Ca-free diet was additionally prepared to measure basal endogenous losses of Ca. The index method and the marker-to-marker method were employed in experiment 1 and in experiment 2, respectively. A replicated 5 × 4 Latin square design was an experimental design in both experiments. Infertile eggs had greater (P < 0.05) CSID of indispensable AA except for lysine and methionine compared with culled chicks. The CSID of indispensable AA did not differ between infertile eggs and unhatched eggs. The CSID of some AA in infertile eggs was greater (P < 0.05) than that in the mixture. The CSID of indispensable AA except for tryptophan was not different between culled chicks and the mixture. Culled chicks had the greatest (P < 0.05) CSTTD of Ca among test ingredients followed by the mixture, infertile eggs, and unhatched eggs. In conclusion, ileal digestibility of most indispensable AA in infertile eggs was greater than that in culled chicks and culled chicks had the greatest Ca digestibility among hatchery byproducts.