Litter Size and Neonatal Survival
| Parameter . | Genotype . | |||
|---|---|---|---|---|
| . | Wild-Type . | G−/− . | GM−/− . | G−/−GM−/− . |
| No. of mating pairs active | 29 | 9 | 20 | 10 |
| Total no. of litters born | 96 | 25 | 45 | 25 |
| No. of pups born per litter (mean ± SD)† | 8.6 ± 3.0 | 8.0 ± 2.9 | 7.3 ± 3.5* | 7.0 ± 2.5* |
| No. of pups weaned per litter (mean ± SD)† | 6.5 ± 3.9 | 7.0 ± 3.0 | 5.6 ± 3.3 | 4.3 ± 3.3* |
| Crude neonatal mortality rate (%) | 24 | 12* | 23 | 39* |
| Percentage of male pups at weaning (mean ± SD) | 49 ± 20 | 43 ± 17 | 55 ± 23 | 43 ± 22 |
| Parameter . | Genotype . | |||
|---|---|---|---|---|
| . | Wild-Type . | G−/− . | GM−/− . | G−/−GM−/− . |
| No. of mating pairs active | 29 | 9 | 20 | 10 |
| Total no. of litters born | 96 | 25 | 45 | 25 |
| No. of pups born per litter (mean ± SD)† | 8.6 ± 3.0 | 8.0 ± 2.9 | 7.3 ± 3.5* | 7.0 ± 2.5* |
| No. of pups weaned per litter (mean ± SD)† | 6.5 ± 3.9 | 7.0 ± 3.0 | 5.6 ± 3.3 | 4.3 ± 3.3* |
| Crude neonatal mortality rate (%) | 24 | 12* | 23 | 39* |
| Percentage of male pups at weaning (mean ± SD) | 49 ± 20 | 43 ± 17 | 55 ± 23 | 43 ± 22 |
Data collected for all mating pairs of the given genotypes active over a continuous 6-month period in the same conventional animal house environment. Mating pairs were all crosses between pairs of the genotype shown in the respective column.
P < .05 v wild-type.
P < .05 for heterogeneity across all genotypes.