Reproduction Responses of Broiler-Breeders to Anticoccidial Agents

Abstract

Two experiments were conducted to determine the effects of anticoccidial agents on production and reproduction of broiler breeders. In Experiment 1, nicarbazin (NCZ) was fed at 20, 50, and 100 ppm. There was no depression in egg production, egg weight, or fertility from feeding these levels. As level of NCZ increased, there was a linear decrease in hatchability. The amount of 4,4'-dinitrocarbanilide (DNC) in the egg yolks increased linearly as the levels of NCZ went up; the degree of egg-shell depigmentation was directly related to the level of NCZ fed starting at 50 ppm. Experiment 2 utilized a different strain of broiler breeders. Halofuginone (3 ppm), maduramicin (5 ppm), monensin (100 ppm), narasin (70 ppm), NCZ (125 ppm), robenidine (33 ppm), and salinomycin (60 ppm) were fed to broiler breeders at the levels listed. Only NCZ reduced egg production. Narasin induced a reduction in egg weight. Both narasin and salinomycin caused a significant drop in hatchability. Feeding NCZ also induced a rapid and more severe decrease in hatchability. Monensin was the only anticoccidial agent that reduced fertility. Halofuginone, maduramicin, and robenidine had no biologically significant effect on henday production, egg weight, hatch of fertile eggs, or shell depigmentation. Feeding NCZ at 125 ppm caused a complete bleaching of brown-shell eggs by the 3rd consecutive day of treatment; but 7 days after NCZ was withdrawn from the feed, pigmentation returned to the pretreatment level.

Forty years of monensin for the control of coccidiosis in poultry

“…In the United States, monensin is not approved for use in laying chickens or birds more than 16 wk of age. Monensin reduced fertility when given at 100 mg/kg to broiler breeders but had no effect on egg production, egg weight, or egg hatch (Jones et al, 1990).…”

Opinion of the Scientific Panel on additives and products or substances used in animal feed (FEEDAP) on the efficacy and safety of the coccidiostat Koffogran

“…It prevents maturation of the follicles which also leads to hypercholesterolemia and hypercalcaemia. At 125 mg kg -1 feed nicarbazin reduced egg production by 65 % and inhibited completely the hatchability (Jones et al, 1990). In another experiment pigmentation was impaired at 25 mg kg -1 feed and hatchability at 50 mg kg -1 feed (Hughes et al, 1991).…”

Cross-contamination of non-target feedingstuffs by nicarbazin authorised for use as a feed additive - Scientific opinion of the Panel on Contaminants in the Food Chain

“…At 125 mg/kg reduction of egg production, egg weight, egg yolk mottling were observed but egg quality as measured by Haugh Units was unaffected by the treatment (Jones et al, 1990b).…”

“…In another study, nicarbazin was fed to White Leghorns layers at 0, 20, 50,100 and 125 mg/kg feed for ten days and hatchability and egg shell pigmentation was decreased at dietary concentrations of 50 and 100 mg/kg feed, and but fertility, egg production and egg weight fertility were not affected (Jones et al, 1990b). At 125 mg/kg reduction of egg production, egg weight, egg yolk mottling were observed but egg quality as measured by Haugh Units was unaffected by the treatment (Jones et al, 1990b).…”