Nutritional aspects and reproductive management of roosters in Brazil

Abstract

Although fertility rates are dependent on both sexes, this characteristic is most often associated with males. For example, the practice of spiking, in which males with undesirable characteristics are replaced with younger males, is often used to improve fertility rates. Dietary restrictions may offset genetic shortcomings to some extent, but nutritional deficiencies due to dietary restrictions may themselves reduce the efficiency of breeding systems. Thus, the challenge is to maintain rooster fertility even when they are receiving diets that meet the nutritional requirements for females. Subjective visual selection is often used for diagnosis of roosters as being unfit for reproduction, with those deemed as overweight or underweight, or those with too small a comb and/or too slightly pigmented, among other phenotypic parameters, being removed. Diagnosis of infertility may only be confirmed after sperm quality evaluation, with reliance on visual diagnosis often resulting in discarding of roosters suitable for reproduction but with unfavourable visual characters. This review aims to characterise reproductive management of roosters in Brazil, highlight aspects of their physiological and sperm quality parameters, and explore nutritional strategies that might contribute to extending their reproductive life.

Keywords:

• broiler breeders
• seminal quality
• nutrition
• Brazil