recognize their twin-born kids. The hour post-partum and parity of does did not significantly affect Ž
. P 0.05 their kid recognition ability. q 2000 Elsevier Science B.V. All rights reserved.
Keywords: Goat maternal–filial bond; Twins; Separation response; Recognition ability
1. Introduction
Breed and litter size are two important factors that affect the abilities of ewes and Ž
. their lambs to recognize each other. For instance, Stevens et al. 1982 reported that
many fined wooled Merinos with twins became permanently separated from one twin on the first day of birth due to the ewe moving away and leaving the lamb behind. The
ewes appeared to be unconcerned if followed by only one lamb. This problem, however, does not seem to occur in other types of Merino sheep and in British breeds, which
Ž .
appear to be aware of both twins Arnold, 1985 . Studies have also shown that 12-h-old Border Leicester = Merino crosses are able to recognize their mothers more readily than
pure-bred Merino lambs of the same age when they are close together, regardless of Ž
whether they are born as singles or as twins Nowak et al., 1987; Nowak and Lindsay, .
Ž .
1990 . Nowak 1989 reported that single- and twin-born Merino lambs had striking differences in their ability to recognize their mothers. While it took up to only 24 h for
single-born lambs to recognize their mothers, it took twin-born lambs 2–3 days to do so. Ž
. Nowak 1989 further reported that single-born lambs were significantly more attracted
to an ewe at 18 and 24 h post-partum than were multiple lambs in a two-choice situation. The single-born lambs were also better at recognizing their mothers and spent
more time with them than multiple-born lambs. In another study, 24 h single-born lambs were found to be better at discriminating between their mothers and alien dams at a
Ž .
distance of less than 50 m Nowak et al., 1990 . Contrary to these findings, Oppong- Ž
. Anane 1991 did not find any significant difference in the dam recognition response
between 18-h-old single- and twin-born Merino lambs. There is a paucity of information on the effect of litter size on the dam recognition ability of newborn goats. Information
on tropical breeds of goats is even more scarce. In our previous study, we reported poor
Ž .
dam recognition ability of single-born West African dwarf goats Addae et al., in press . Ž
. At 36 h of age, nine out of 14 single-born kids i.e. 64 could recognise their dams
while at 48 h, 75 of the kids was able to recognize their dams. It is not clear whether the dam recognition ability of twins would be different from that of single-borns because
goats, as ‘hiders’, leave their young ones for periods to graze during the first few days after parturition. Thus, for both single- and twin-born kids, the periods of separation
from their dams are the same. The objective of this study, therefore, was to investigate Ž .
i the response of twin-bearing West African dwarf goats and their kids to separation Ž .
and ii the existence of mutual recognition between dams and their twin-born kids.
2. Animals, materials and methods
