ENVIRONMENT AND HEALTH Behavioral Correlates of Male Mating Success in a Multisire Hock as Determined by DNA Fingerprinting1 MEJ. JONES2 and J. A. MENCH3 Department of Poultry Science, University of Maryland, College Park, Maryland 20742 (Received for publication September 13, 1990)
1991 Poultry Science 70:1493-1498
the use of an indicator such as observed Historically, correlations between behavior completed matings permits the study of social and fertility have been important considera- dominance effects in such flocks (Justice et al, tions in poultry breeding programs. If higher 1962; Siegel, 1965; Cheng et al, 1985), the male fertility could be associated with particu- reliability of this method in determining the lar behavioral traits, birds showing or not number of offspring sired by an individual showing those traits could be retained or male is uncertain because hens can store live culled, thus improving fertility rates in breed- spermatozoa from different males for several ing flocks. Several behavioral factors appear to weeks (Van Drimmelen, 1946). There may be important in influencing male breeding also be multiple paternity within a clutch due success (Ottinger and Mench, 1989), particu- to factors other than mating frequency, such as larly position in the social dominance hierar- the time of day when mating occurs (Parker, 1945) and each male's place in the sequence of chy. males mating with a given female (Compton et The association between male social domi- al, 1978). nance and fertility has been investigated in To overcome the problems associated with several studies (Guhl et al, 1945; Guhl and Warren, 1946; McDaniel and Craig, 1959). using witnessed matings as an indicator of Accurate determination of the fertility of fertility, the correlation of dominance with individual males within a multisire flock, fertility has also been studied using hereditary however, has proven problematicaL Although characteristics, such as plumage color or comb shape, to verify paternity (Guhl and Warren, 1946). However, in this type of study, sample sizes are of necessity small due to the limited Scientific Article Number A6143, Contribution Num- number of distinguishable traits. It is also ber 8310, of the Maryland Agricultural Experiment Station. difficult to control for breed effects on mating 2 Current address: Department of Poultry Science, Virsuccess when using morphology to determine ginia Polytechnic Institute, Blacksburg, VA 24061. paternity. ^To whom correspondence should be addressed. INTRODUCTION
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Downloaded from http://ps.oxfordjournals.org/ at UNIVERSIDAD DE SEVILLA on April 14, 2015
ABSTRACT The fertility of an individual rooster within a multi-sire flock may be influenced by a number of behavioral considerations, including frequency and tuning of matings and the male's position in the social dominance hierarchy. The relationship between behavior and fertility has proven difficult to assess, however, because there are a limited number of heritable morphological traits that can be used to determine paternity. The objectives of the present study were to use DNA fingerprinting to determine paternity in domestic fowl and to assess some behavioral and physiological correlates of mating success. Sixty day-old chicks from each of two commercial breeds, DeKalb White Leghorn (L) and Warren Color-Sexed (W), were reared in either same-breed or mixed-breed groups. At 43 wk of age, all females and six randomly selected males were mixed into one large pen. Male aggressive and mating behaviors were recorded over a 4-mo period. Fertility of individual sires was determined by DNA fingerprinting and pedigree analysis of chicks. Dominance rank and the frequencies of both completed matings and mating attempts were positively correlated with fertility (P
1991 Poultry Science 70:1493-1498
the use of an indicator such as observed Historically, correlations between behavior completed matings permits the study of social and fertility have been important considera- dominance effects in such flocks (Justice et al, tions in poultry breeding programs. If higher 1962; Siegel, 1965; Cheng et al, 1985), the male fertility could be associated with particu- reliability of this method in determining the lar behavioral traits, birds showing or not number of offspring sired by an individual showing those traits could be retained or male is uncertain because hens can store live culled, thus improving fertility rates in breed- spermatozoa from different males for several ing flocks. Several behavioral factors appear to weeks (Van Drimmelen, 1946). There may be important in influencing male breeding also be multiple paternity within a clutch due success (Ottinger and Mench, 1989), particu- to factors other than mating frequency, such as larly position in the social dominance hierar- the time of day when mating occurs (Parker, 1945) and each male's place in the sequence of chy. males mating with a given female (Compton et The association between male social domi- al, 1978). nance and fertility has been investigated in To overcome the problems associated with several studies (Guhl et al, 1945; Guhl and Warren, 1946; McDaniel and Craig, 1959). using witnessed matings as an indicator of Accurate determination of the fertility of fertility, the correlation of dominance with individual males within a multisire flock, fertility has also been studied using hereditary however, has proven problematicaL Although characteristics, such as plumage color or comb shape, to verify paternity (Guhl and Warren, 1946). However, in this type of study, sample sizes are of necessity small due to the limited Scientific Article Number A6143, Contribution Num- number of distinguishable traits. It is also ber 8310, of the Maryland Agricultural Experiment Station. difficult to control for breed effects on mating 2 Current address: Department of Poultry Science, Virsuccess when using morphology to determine ginia Polytechnic Institute, Blacksburg, VA 24061. paternity. ^To whom correspondence should be addressed. INTRODUCTION
1493
Downloaded from http://ps.oxfordjournals.org/ at UNIVERSIDAD DE SEVILLA on April 14, 2015
ABSTRACT The fertility of an individual rooster within a multi-sire flock may be influenced by a number of behavioral considerations, including frequency and tuning of matings and the male's position in the social dominance hierarchy. The relationship between behavior and fertility has proven difficult to assess, however, because there are a limited number of heritable morphological traits that can be used to determine paternity. The objectives of the present study were to use DNA fingerprinting to determine paternity in domestic fowl and to assess some behavioral and physiological correlates of mating success. Sixty day-old chicks from each of two commercial breeds, DeKalb White Leghorn (L) and Warren Color-Sexed (W), were reared in either same-breed or mixed-breed groups. At 43 wk of age, all females and six randomly selected males were mixed into one large pen. Male aggressive and mating behaviors were recorded over a 4-mo period. Fertility of individual sires was determined by DNA fingerprinting and pedigree analysis of chicks. Dominance rank and the frequencies of both completed matings and mating attempts were positively correlated with fertility (P
