This work was done to assess heterosis levels generated in
meat goat kids produced in a three-breed diallel mating scheme. Heterosis
(hybrid vigor) is an increase in animal performance derived through the
practice of crossbreeding. The meat goat breeds involved were the Boer,
Kiko and Spanish.
The Boer goat (B) is a meat goat developed in South Africa
and imported to the US in the mid-1990s. The Kiko Goat (K) is a meat goat
developed in New Zealand and also imported to the US in the mid 1990s. The
Spanish goat (S) is a common US feral goat type that has evolved in the
southern and southwestern states over the last few centuries.
In the spring of 2004, the TSU meat goat breed evaluation
project produced 29 BB, 31 KK, 27 SS, 18 BK, 29 KB, 30 KS, 25 SK, 18 SB,
and 32 BS kids. (The first letter designates the paternal breed, the
second letter represents the maternal breed). Heterosis was determined on
the following economically important traits; birth weight, preweaning
average daily gain, weaning weight (3 months of age), and preweaning
survival rate.
Birth weight showed little to no heterosis among the breed
pairings. Preweaning average daily gain shows 5.52% heterosis between B
and S, 2.22% heterosis between B and K, and no heterosis was expressed
between K and S. For weaning weight, B and S generated 6.42% heterosis, B
and K expressed 3.16% heterosis and no heterosis was shown between K and
S. For preweaning survival rate, B and S had 7.43% heterosis, whereas no
heterosis was expressed between B and K or between K and S.
In summary, kids produced by crossing Boer with Spanish
experienced the highest level of heterosis for three significant
preweaning performance traits. Kiko crosses generated lower heterosis
levels. Heterosis allowed Boer-Spanish reciprocal crosses to outperform
both parental genotypes for growth traits; however, they did not
outperform the purebred KK kids. This first year of data indicates that
levels of heterosis vary among meat goat breed crosses.