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Reproductive
and fitness indicators among Boer, Kiko, and Spanish does managed on
pasture in central Tennessee (Year 1)
R.
Browning, Jr., T. Payton, B. Donnelly, P. Pandya,
M. L. Leite-Browning, W. Hendrixson, M. Byars
Institute of Agricultural and Environmental Research
Seminar Series
Tennessee State University, Nashville, TN
November 30, 2005
Boer (B), Kiko (K), and Spanish (S) straightbred does
representing a broad base of within-breed genetic lines were mated in a
complete 3-breed diallel in the first year of a four-year breeding
project. For Year 1, 234 kids were tagged at birth during the spring of
2004. Litter size and litter weight at birth were affected by sire breed
x dam breed interactions (P < 0.01). Litter 90-d adjusted weaning
weights were affected (P < 0.01) by dam breed. Litters weaning
weights from B dams were lower (23 kg) than for K or S (31 and 29 kg,
respectively). The ratio of litter weight weaned to doe weight at
weaning was greater (P < 0.01) for S compared to B dams (71 vs 58
± 3%), KK were intermediate (66%). Breeds differed (P < 0.01) for
lameness cases treated during the year. Boer required more (P <
0.01) treatments for lameness (1.77 cases/doe) than S (0.60 cases/doe)
or K (0.47 cases/doe). A higher (P < 0.01) frequency of B (52.3%)
required multiple hoof treatments per year compared with S (19.2%) or K
(10.5%). Breeds differed (P < 0.01) for unscheduled anthelmintic
treatment. Extra dewormings were more numerous for B (0.53 cases/doe)
than for S (0.11 cases/doe) or K (0.07 cases/doe). A higher (P <
0.01) frequency of B (40.5%) received extra dewormings during the year
compared to S (6.4%) or K (2.6%). Fecal egg counts (FEC) were determined
on a random subset of does across kidding groups as kids approached 3 mo
of age (June and August). Breed affected (P = 0.04) log
transformed FEC with values higher (P < 0.04) for B than for S.
Geometric mean FEC for B, K and S were 606, 307, and 237 eggs/g,
respectively. Kid attrition rate was higher (P < 0.01) for B dams (38%)
compared with K and S dams (8% each). As measures of whole herd
performance, B does weaned a lower (P < 0.01) kid crop percent
and adjusted litter weight per doe exposed (138%, 22.33 kg) compared to
K (183%, 32.09 kg), S does were intermediate (191%, 27.51 kg). Lower
frequencies (P < 0.01) of BR does weaned kids at 3 mo (76%) and
survived though the production year (79%) compared with SP (96%, 98%)
and KK does (100%, 100%). Preliminary results from the first production
year suggest that significant differences exist among meat goat breeds
for reproductive and general fitness traits under southeastern US
conditions.
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