Fertility and whelping
The whelping rates and fertility of a number of breeds, including Dachshunds, are discussed in Biology of Reproduction and Modern Reproductive Technology in the Dog by Catharina Linde Forsberg and Karine Renaud and The Genetics of the Dog by Ostrander and Ruvinsky.
Among the figures quoted are:
91% of Dachshunds mated (in a 12 year period) whelped and this is among the highest fertility quoted.
13.3% of Dachshund bitches needed veterinary assistance during whelping (compared with 9.1% in Golden Retrievers – lowest – and 87.5% in Pekingese – highest). In our Dachs-Life 2012 survey it was reported that 6.5% of bitches that had been bred from suffered from Dystocia (difficulty whelping). The Dystocia rate was 4.6% in Miniatures and 10.8% in Standards.
13.3% of Dachshund bitches required a caesarian section (compared with Swedish Lapphunds 1.6% and Bulldogs 43%).
In a study of 10,810 litters (224 breeds), the size of the breed and the age of the bitch were the main factors determining litter size by natural matings. Litter size is smaller in bitches aged 1-2, increases up to the age of 3-4 and decreases sharply after 5-6 years.
Influence of inbreeding on litter size and the proportion of stillborn puppies in dachshunds:
In a different study, factors influencing the litter size of puppies and the number and the proportion of stillborn puppies per litter were analysed in normal-sized German dachshunds. Data was available for litters registered from 1987 to 2002 in the German dachshund kennel club. The records studied here contained 42,855 litters. The mean litter size was 5.22 +/- 2.01 puppies. The proportion of puppies born dead per litter was 6.6%. The age of dam, the puppy's year and month of birth, the hair type and the inbreeding coefficients of the puppies, the sire, and the dam were significant on the litter size and the number and the proportion of puppies born dead.
The litter size decreased and the percentage of puppies born dead increased with increasing inbreeding coefficients of the puppies, dams, and sires. The increase of the inbreeding coefficient of the puppies by 1% led to a 0.06% higher percentage of puppies born dead per litter. The increase of the inbreeding coefficients of the dam and the sire by 1% resulted in 0.02% and 0.007% higher percentages of puppies born dead.
Young and older dams had smaller litter sizes than middle-aged dams. The percentage of puppies born dead per litter increased with increasing age of the dam. In the recent birth years, the litter size and the percentage of puppies born dead increased in German dachshunds.