The exploitation of industrial strains of chickens in the Sahelian climate of Niger is characterized by a decline in performance and significant costs associated with their maintenance. In contrast, local chickens are...The exploitation of industrial strains of chickens in the Sahelian climate of Niger is characterized by a decline in performance and significant costs associated with their maintenance. In contrast, local chickens are well adapted to these environmental conditions but with poor production performance. Genetic selection of these local chickens could improve their productivity. The first step is to determine if the genetic parameters of their growth are high enough to ensure a successful selection strategy. To do so, weekly weights of 69 parents and 119 offspring were followed for 20 weeks. The heritability and genetic correlations of these weights were estimated through the Bayesian approach using the MCMCglmm package on R software. At hatching, weights ranged from 23 to 25 g. At 20 weeks, these weights ranged from 1031 to 1052 g for females and 1308 to 1445 g for males. Heritabilities for hatch weights at 4, 8, 12, 16, and 20 weeks of age were estimated to be 0.56, 0.31, 0.52, 0.53, 0.52 and 0.48 respectively and all genetic correlations were positive. In particular, weight at 8 weeks of age showed both good heritability (h<sup>2</sup> = 0.52) and strong, positive genetic correlations with weights at older ages. These results indicate that genetic selection to improve weight at 8 weeks of age would be a good strategy to improve the overall growth performance of these chickens.展开更多
In poultry,feed based on maggots,like larvae of black soldier fly(Hermetia illucens) is an attractive option to substitute current ingredients which are expensive and often in direct or indirect competition with human...In poultry,feed based on maggots,like larvae of black soldier fly(Hermetia illucens) is an attractive option to substitute current ingredients which are expensive and often in direct or indirect competition with human food.Little information is currently available on the utility of these larvae in poultry feed,so goals of this study were to determine whether larvae could be reared on horse manure under traditional farming conditions and to evaluate the growth performances of a local poultry fed these larvae and the fatty acids profiles of their meat.After freezing and thawing,larvae were introduced in the feed of Ardennaise chickens between 30 and 80 days of age.Birds in the control group received a commercial standard feed,while those in the treatment group received the same commercial feed in which 8% was substituted with whole fresh larvae corresponding to 2% on a dry matter basis.Means ± standard errors of larval length and weight were 20.67 ± 2.21 mm and 0.14 ± 0.02 g,respectively.Mean larval percentages of dry matter and of substances extractable in diethyl ether were 24.6% and 23.1%,respectively.Larval fatty acids profiles were predominantly composed of lauric acid(28.1%) and palmitic acid(22.0%).Least squares means of weekly weights of chicken,adjusted for the effects of sex,replication and initial weights,were significantly higher(P < 0.05) by 77.03 ± 53.37 g in larvae-fed than in control chickens.All other measurements were not statistically different between larvae-fed and control chicken,including fatty acid profiles,protein content and w6/w3 ratio.展开更多
文摘The exploitation of industrial strains of chickens in the Sahelian climate of Niger is characterized by a decline in performance and significant costs associated with their maintenance. In contrast, local chickens are well adapted to these environmental conditions but with poor production performance. Genetic selection of these local chickens could improve their productivity. The first step is to determine if the genetic parameters of their growth are high enough to ensure a successful selection strategy. To do so, weekly weights of 69 parents and 119 offspring were followed for 20 weeks. The heritability and genetic correlations of these weights were estimated through the Bayesian approach using the MCMCglmm package on R software. At hatching, weights ranged from 23 to 25 g. At 20 weeks, these weights ranged from 1031 to 1052 g for females and 1308 to 1445 g for males. Heritabilities for hatch weights at 4, 8, 12, 16, and 20 weeks of age were estimated to be 0.56, 0.31, 0.52, 0.53, 0.52 and 0.48 respectively and all genetic correlations were positive. In particular, weight at 8 weeks of age showed both good heritability (h<sup>2</sup> = 0.52) and strong, positive genetic correlations with weights at older ages. These results indicate that genetic selection to improve weight at 8 weeks of age would be a good strategy to improve the overall growth performance of these chickens.
文摘In poultry,feed based on maggots,like larvae of black soldier fly(Hermetia illucens) is an attractive option to substitute current ingredients which are expensive and often in direct or indirect competition with human food.Little information is currently available on the utility of these larvae in poultry feed,so goals of this study were to determine whether larvae could be reared on horse manure under traditional farming conditions and to evaluate the growth performances of a local poultry fed these larvae and the fatty acids profiles of their meat.After freezing and thawing,larvae were introduced in the feed of Ardennaise chickens between 30 and 80 days of age.Birds in the control group received a commercial standard feed,while those in the treatment group received the same commercial feed in which 8% was substituted with whole fresh larvae corresponding to 2% on a dry matter basis.Means ± standard errors of larval length and weight were 20.67 ± 2.21 mm and 0.14 ± 0.02 g,respectively.Mean larval percentages of dry matter and of substances extractable in diethyl ether were 24.6% and 23.1%,respectively.Larval fatty acids profiles were predominantly composed of lauric acid(28.1%) and palmitic acid(22.0%).Least squares means of weekly weights of chicken,adjusted for the effects of sex,replication and initial weights,were significantly higher(P < 0.05) by 77.03 ± 53.37 g in larvae-fed than in control chickens.All other measurements were not statistically different between larvae-fed and control chicken,including fatty acid profiles,protein content and w6/w3 ratio.
