Prediction of the Fertility Potential of Broiler Breeder Males

Abstract

Semen Quality Characteristics and FertilityThe selection of males for breeder flocks is usually based on such characteristics as posture, body conformation, maturity, body size, ~~~~ ~ ~ ~ *Ha. Agr. Exp. Sta. Journal Series No. 1062. 95 96condition of the legs and feet, appearance of the head, general health and vigour, and appearance of eyes. Although these characteristics are useful in selecting males they do not assure that high fertility will be obtained. Several attempts have been made to relate various semen quality characteristics to fertility. There is much disagreement in the literature, however, regarding the importance and reliability of semen traits in predicting fertility. Differences can, of course, be expected between the results obtained from natural mating and artificial insemination. Although measurements of semen traits have been succcssful in detecting sterile birds, the prediction of fertilizing capacity appears to be complex and influenced by numerous factors other semen quality.In order to make fertility predictions or male breeding worth predictions based on semen evaluation, high correlations between semen characteristics and fertility must be found. Then a statistical model may be fitted using the semen quality values as independent variables to define the dependent variable, fertility. In addition, when attempting to obtain an estimate of fertility or breeding potential, one must keep in mind that it is influenced by genetical, physiological and social factors.Semen quality characteristics are generally believed to be inherited (Lake, 1971; Marini and Goodman, 1969) and differences in semen characteristics and fertility have been reported between breeds (Parker et al., 1942;Allen and Champion, 1955; Taneja and Gowe, 1961 a and b;McDaniel and Craig, 1962), between inbred lines (Williams and McGibbon, 1956; De-Silva, 1963) and between families (Boone, 1968).Heritability values for such traits as semen quantity, concentration and motility were found to be high (Soller et al. 1965b) as were the repeatabilities of such measurements. Nestor and Brown (1976a) reported that measurements of semen quality made early in the reproductive life of the male were not closely correlated with subsequent evaluations and did not permit accurate prediction of future semen production. Nestor (1976) successfully selected turkeys for increased semen yield, however, there were no consistent changes in percent fertility, percent hatchability of fertile eggs or number of poults per hen associated with the increases in semen yield. Some success also has been reported for the selection for fertility when using frozen chicken semen (Scott et al., 1977).Concentration of spermatozoa in semen has been claimed to be significantly related to fertility (following AI), having a correlation coefficient of 321 (Kamar, 1960) and .481 (Boone, 1968). Others have presented data indicating that it is not significantly related to fertility (

The effect of cooling rate before freezing and the temperature of the semen upon addition of DMSO on the fertilizing capacity of chicken semen stored at —196 °C

“…The correlation between motility and fertilizing capacity of poultry semen has generally been reported to be poor (Lake, 1962 ;Wilson et al, 1979) and this generalization was confirmed in the present study. For example, the addition of DMSO reduced motility immediately by 5 to 15 p. 100 but had no effect on fertility (tables 1 and 2).…”

Influência da idade dos reprodutores de codornas de postura na reprodução, na qualidade de ovos e na morfologia dos órgãos genitais

“…Já em outros trabalhos, comparando galos com 35 e 68 semanas de idade, Rocha Júnior e Baião (2001) concluíram que não houve diferença nas características espermáticas entre as idades. Nos galos, a redução na fertilidade está associada a redução no número de espermatozóides no ejaculado e na redução do volume de sêmen produzido (LAKE, 1989), apresentam também libido diminuída e menor número de cópulas férteis (WILSON et al, 1979). Nas codornas analisadas não foram avaliados os parâmetros seminais dos machos, porém, o numero de espermatozóides fornece uma visão indireta da quantidade de espermatozóides que as fêmeas receberam naquele período.…”

Avaliação de Programas de Alimentação para Matrizes de Corte na Fase de Produção

“…Considerando que os machos tiveram o mesmo manejo sanitário e nutricional, não era esperado efeito deste trabalho sobre a fertilidade dos ovos, ANSAH et al (1977), WILSON et al (1979), HARRIS et al (1984), WILSON et al (1987), HOCKING (1989), HOCKING e DUFF (1989).…”