Parental care in free-ranging dogs, Canis familiaris

Parental care in free-ranging dogs was investigated in Katwa town, India. Six lactating bitches, 4 were monogamous. The gestation period varied from 62 to 65 days. Mean ( +/-S.D.) litter size of 5.83 (+/-1.57) with a sex ratio of 1.69:1 in favour of male was recorded in this study. High mortality (63%) of pups occurred by the age of 3 months. Mothers were in contact with the litters for 13 weeks of the litters' life. There was a negative correlation between the duration of mother-litter contact in any observation session and the age of the pups. Milk feeding by the mothers was continued for 10-11 weeks of the litters' life. The duration of milk feeding in any 30-min observation session reached a maximum of 27.54 min during the 1st week and a minimum of 2.22 min during the 11th week of the litters' life. All the mothers in this study were observed to feed the pups by regurgitation. For the first 2 weeks immediately after parturition. the lactating females were observed to be more aggressive to protect the pups. The four males (male parents) were in contact with the litters as 'guard' dogs for the first 6-8 weeks of litters' life. In absence of the mothers, they were observed to prevent the approach of strangers by vocalizations or even by physical attacks. Moreover, one male fed the litter by regurgitation showing the existence of paternal care in free-roaming domestic dogs. (C) 2004 Elsevier B.V. All rights reserved.