Sheep - AgRIS

month post-weaning individual feedlot trial ranged from 13.97 to 19.78%, the highest (19.78 ±
2.56) being in Nali and so also the dressing percentage ( 44.32 to 48.3%) on live weight basis
(5 months), the highest (48.25 ± 3.29) for Nali. In Magra, 6 months age was the most
profitable age for slaughter. Dressing percentage on empty weight basis varied from 50.07 to
53.95 and the total boneless meat percentage from 38.40 to 42.32 in Magra lambs slaughtered
at 6 to 9 months of age. Results of the All India Co-ordinated Research Project on Sheep
Breeding indicated that of the native breeds included in the crossbreeding programme at the
Central Sheep & Wool Research Institute, Avikanagar (semi-arid), Malpura lambs were
superior to Sonadi in terms of efficiency of feed conversion and dressing percentage. They
were also they were better convertor of milk to body tissues than the Sonadi lambs. The meat
bone ratio was somewhat higher in Malpura as compared to the high and low energy feeds.
The heritability estimates of body weight from birth to one year of age varied from 0.11 ± 0.3
to 0.45 ± 0.66 but those for body weights other than of 6 and 12 months were small and they
did not have so much genetic and phenotypic correlations (especially the weaning weight)
between body weight of 9 and 12 months as at 6 months. The pooled heritability estimates of 6
month body weight were high and almost equal to that of 9 and 12 months. Furthermore the 6
month body weight bore high genetic and phenotypic correlations (o.664 & 0.785 respectively)
with the yearling body weights. These genetic parameters indicated that the body weight at 6
months of age should be a best selection criterion for improving market weight and adult body
size and in turn the productivity.
Crossing among indigenous breeds
Some exploratory trials on crossing indigenous breeds for mutton production have also
been undertaken. Grading up with indigenous breed (Bikaneri) was undertaken in Andhra
Pradesh, Karnataka, Tamil Nadu and Uttar Pradesh. The results of this experiment were not
very encouraging in the southern states, as the Bikaneri did not survive long because of their
poor adaptation to hot and humid climate. Crossbreeding of North Indian carpet wool breeds
(Nali and Lohi) with South Indian mutton type breeds (Nellore and Mandya) at the Haryana
Agricultural University did not markedly improve the body weight gains, efficiency of feed
conversion and dressing percentage in the crosses compared to the North Indian Carpet wool
breeds. The efficiency of feed conversion ranged from 13.97 to 19.78% and the dressing
percentage on live weight basis from 44.32 to 48.3%, both being higher in purebred Nalis. The
results of crossbreeding of indigenous Bihar sheep with Bikaneri indicated that crossbred lambs
grew significantly faster than the Bikaneri and Bihar lambs and that the average live weight of
Bikaneri and Bihar sheep and their grades differed significantly at one, two and three months of
age.
Crossing among indigenous breeds
Some exploratory trials on crossing indigenous breeds for mutton production have also
been undertaken. Grading up with indigenous breed (Bikaneri) was undertaken in Andhra
Pradesh, Karnataka, Tamil Nadu and Uttar Pradesh. The results of this experiment were not
very encouraging in the southern states, as the Bikaneri did not survive long because of their
poor adaptation to hot and humid climate. Crossbreeding of North Indian carpet wool breeds
(Nali and Lohi) with South Indian mutton type breeds (Nellore and Mandya) at the Haryana
Agricultural University did not markedly improve the body weight gains, efficiency of feed
conversion and dressing percentage in the crosses compared to the North Indian Carpet wool
breeds. The efficiency of feed conversion ranged from 13.97 to 19.78% and the dressing
percentage on live weight basis from 44.32 to 48.3%, both being higher in pure bred Nalis. The
results of crossbreeding of indigenous Bihar sheep with Bikaneri indicated that crossbred lambs
grew significantly faster than the Bikaneri and Bihar lambs and that the average live weight of
Bikaneri and Bihar sheep and their grades differed significantly at one, two and three months of
age.
The dressing percentage on live and empty body weight bases was higher in F 1 s arising
from Dorset and Suffolk crosses with Malpura and Sonadi. There was comparatively a higher
increase in Dorset crosses than the Suffolk ones. Mandya and Nellore crosses with Dorset, and
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