title: The influence of breed and sex on the incidence of mortalities and skin tears in broiler carcasses.
abstract: The effects of nutrition, breed and sex on the incidence of mortalities and of skin tears on broiler carcasses were studied. Both sexes of 2 breeds, Hubbard and Ross, were given 4 dietary treatments consisting of a normal level of vitamin and mineral premix plus 300 ppm furazolidone, twice normal premix inclusion level plus 300 ppm furazolidone, a normal level of vitamin and mineral premix, and twice normal mineral premix inclusion level. A coccidiostat containing the active ingredient halofuginone was included at 6 ppm, twice the recommended dosage. Starter, grower and finisher diets were fed respectively up to Day 20, Day 30 and Day 48. Group growth performances, mortalities and the incidence of torn skin were monitored on both the live birds and carcasses. The effect of the different nutritional treatments on skin tears was not significant (P = 0.9533), as was the breed effect (P = 0.0547). However, the effect of sex was significant (P = 0.0044), the incidence in hens being higher. Mortalities among the Hubbard were significantly greater than among the Ross (P = 0.0001). Hens showed a slightly higher mortality rate than roosters, tending towards significance at the 5% level (P = 0.0554).
authors.affiliation: Department of Livestock Science, Faculty of Agriculture, University of Pretoria, Republic of South Africa.
authors.forename: N H
authors.initials: NH
authors.lastname: Casey
authors.forename: G A
authors.initials: GA
authors.lastname: Smith
authors.forename: R I
authors.initials: RI
authors.lastname: Crosley
mesh_terms: D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001947:Breeding; D002645:Chickens; D011201:Poultry Diseases / Q000401:mortality*; D012737:Sex Factors; D012867:Skin / Q000293:injuries*