The inheritance and effect on production of polledness in four crossbred lines of beef cattle

Abstract

Changes in the frequency of the poll gene and the effect of polledness on production were measured from 1970 to 1979 in four closed lines of crossbred cattle. The lines were Africander cross (AX), Braham cross (BX) and two Hereford × Shorthorn (HS lines, one selected for production (HSS) and one a control line (HSR).Calves were classified as horned, polled or scurred. Except in the HSS line, horned males were more common than horned females. Horned HS bulls sired only horned calves when mated to horned cows but corresponding matings of AX and BX breeds produced some polled progeny. The incidence of scurs was highest in the AX line, lowest in the HS lines and higher in males than females. These observations are discussed in relation to existing models of inheritance of horn-type.Prior to 1970 the frequencies of the poll gene declined from their initial values in the BX and HS lines and increased in the AX line. These changes were ascribed to random genetic drift. After 1970 the frequency of the poll gene remained stable in all lines.No significant differences were observed between horned and polled cattle in live weight, fertility or mortality rates indicating that polledness had no detrimental effect on production in these lines.

A study of growth and carcass traits in dehorned and polled composite bulls

“…Research data from Frisch et al (1980), Lange et al (1990), Stookey and Goonewardene (1996) and Goonewardene et al (1999), and this study suggest that the phenotypic differences influencing production traits between genetically horned and polled cattle are small and insignificant. As such, breeding for polledness can be recommended as a non-invasive means of progressively eliminating the need to dehorn feeder-slaughter cattle.…”

A comparison of reproductive and growth traits of horned and polled cattle in three synthetic beef lines

“…Despite some evidence in the literature suggesting that there is little or no difference between horned and polled genotypes of some cattle breeds (Frisch et al 1980;Lange 1989;Stookey and Goonewardene 1996), horned and polled cattle breeders tend to breed within horn status groups. Blockey and Taylor (1984) reported reduced fertility among polled Hereford bulls due to a genetic, premature spiral deviation of the penis, which may discourage the use of polled Hereford bulls in some circumstances.…”

A comparison of production traits and welfare implications between horned and polled beef bulls

“…A study by Koots and Crow (1989) (Long and Gregory 1978). In another study, the frequency of scruring ranged from 3 to ll%io in males and from I to 7%o in females (Frisch et al 1980) and was dependent on the type of cross. Although scurs would tend to inflict some bruising of carcasses, more bruising could be expected due to horns, which are usually larger and longer.…”

“…1996 (Estes 1991 (Lange 1989). Work done in Australia using various beef breeds (Frisch et al 1980) showed no differences between horned and polled crossbred lines in live weight, fertility and mortality rates indicating that polledness caused no detrimental effect on production. (Meischke et al 1974;Grandin 1980 (Goonewardene and Hand 1991).…”

“…(Meischke et al 1974;Grandin 1980 (Goonewardene and Hand 1991). Although dehorning is recommended either shortly after birth (Grandin 1980) or within 2 mo (Battaglia and Mayrose 1981) The adjustment factor of 0.032 cm d-l was used for both breeds (Lunstra et al 1988 However, some research has shown that the differences in pre-weaning gain and carcass traits between polled and horned cattle are small and not significant (Marlowe et al 1962;Frisch et al 1980;Lange 1989; Lange et al 1990). Calf mortality has been reported to be similar between polled and horned cattle (Frisch et al 1980) and no differences in fertility were observed (Frisch et al 1980;Lange 1989).…”