Breed compostition of the Irish cattle herd.

Abstract

Information was collected on cow and sire breeds in both dairy and suckler herds in the National Farm Survey (NFS) in autumn 1998. The number of farms included in the analysis was 1030 with farms containing less than 2 economic size units (equivalent to 3 to 4 dairy cows) excluded from the sample. The main findings of the survey were as follows: • Ninety-eight percent of dairy cows and 96% of dairy herd replacements were Friesian/Holstein • The suckler cow herd contained 46% early-maturing breed crosses (Hereford 31%, Aberdeen Angus 12% and Shorthorn 3%) 2% Friesians, 48% of the three main continental breed crosses (Charolais 17%, Simmental 16%, Limousin 15%) and 4% other (mainly continental crosses). Compared to the adult cows herd replacements had less early-maturing breed crosses and Friesians (total 42%) and more (55%) of the three main continental breed crosses (Charolais 20%, Simmental 15%, Limousin 20%). • Overall, in 1998, it was estimated that the national cow herd consisted of 52% Friesian/Holstein, 23% early maturing breed crosses and 26% late maturing breed crosses. • Forty-seven percent of dairy cows were bred to Friesian/Holstein sires, 26% were bred to early maturing sire breeds and 27% were bred to continental sire breeds. The corresponding figure for dairy herd replacements were 40%, 46% and 13%. • Seventeen percent of suckler cows were bred to early maturing sire breeds, 46% were bred to Charolais, 16% were bred to Simmental, 17% were bred to Limousin and the remaining 6% were bred to mainly other continental breed sires. The sires used on suckler herd replacements were 43% early maturing breeds, 16% Charolais, 10% Simmental, 25% Limousin and 5% other. • Based on the sire breeds used in 1998, the breed composition of the 1999 calf crop was estimated to be 24% Friesian/Holstein, 24% early maturing breeds, 24% Charolais cross, 10% Simmental cross, 12% Limousin cross and 6% other (mainly other continental crosses). • Although the proportion of continental breed crosses in the calf crop continues to increase (48% in 1993 to 52% in 1999), the use of continental sire breeds is declining in the dairy herd (from 33% in 1992 to 27% in 1998), particularly where AI is the method of breeding. However, this trend may be at an end as the 1999 AI figures to date (September 30) show substantial decreases in Hereford and Aberdeen Angus inseminations with increases in Belgian Blue, Limousin and Friesian/Holstein. • The dairy herd is a relatively unimportant source of the better quality animals accounting for only 25% of total continental breed crosses which have a lower proportion of continental breed genes than those from the suckler herd. • It was estimated that the 1999 calf crop from the suckler herd consisted of 18% early maturing breeds, 29% of half to threequarters continental breed genes and 53% containing at least three-quarters continental breed genes. • A total of 48,200 herds used bulls. The proportion of bulls of each breed used were 9% Frieisan/Holstein, 17% Hereford, 11% Aberdeen Angus, 1% Shorthorn, 29% Charolais, 12% Simmental, 16% Limousin and 5% other. Continental breeds accounted for 38% and 84% of bulls on dairy and suckler farm, respectively. • In the present study the number of animals (cows plus replacements) bred to continental sire breeds was 1.22 million of which 40% were by AI. • National AI figures show that the total number of inseminations (excluding DIY) have declined from 1.03 million in 1992 to 0.79 million in 1998. • Assuming that the suckler cow should be at least half continental breeding and that Belgian Blue crosses are unsuitable if increases in calving problems are to be avoided then the dair y herd may provide as little as 25% of suitable suckler herd replacements. Thus, the main source of replacements would be from within the suckler herd. Factors to be considered include hybrid vigour which involves crossbreeding, milk production potential of the cow and the fact that the most widely used terminal sire is Charolais. In these circumstances one suitable crossbred cow would be obtained from alternate crossing with Limousin and Simmental sires. • Heat synchronisation was used on 3% of herds. The figures for dairy and suckler herds was 6.8% and 0.5%, respectively. • Vaccination for leptospirosis was used on 29% of dairy farms and 4% of suckler farms.