Live weight changes during lactation and its relationship with milk off-take and yield in West African Dwarf and Red Sokoto goats intensively managed within the humid zone of Nigeria
This study focused on changes in doe live weight during lactation in West African dwarf (WAD) and Red Sokoto (RS) goats intensively managed within the humid zone of South-western Nigeria. The data analysed was based on 202 weekly records. from 17 lactations of 8 WAD and 9 RS goats from year 2000-2002. Mean live weight for RS does (21.16+0.34 kg) was higher (P<0.001) than the estimate (18.15+0.34 kg) for WAD does. Live weight decreased (P>0.05) from parturition up to fourth week and increased (P> 0.05) thereafter till the 12th week of lactation. There was no significant interaction between breed and week of lactation. Cumulative mean weight changes of 0.16+4119 kg for WAD and 0.38+0.22 kg for RS were not significantly different, Does had higher (P<0.001) body weights during the late- wet and early-dry seasons than during late-thy and early-wet seasons.. Live weight increased .significantly (P<0.001) with parity of doe, the trend being maintained with regards to cumulative weight change. Does that suckled male kids were less superior in body weights. This was reflected by a negative cumulative weight change. Live weight was positively con-elated with milk yield (rp = 0.24; P<0.05,4 estimated at 270.61+13.48 ml and 281.98+ 13. 17 ml respectively for RS and WAD goats (P>0.05). Corresponding values for milk off-take were (.14.09+3.64 and 16,45+3.56 ml; P>0.05), Milk off-take was lowly correlated with live weight (rp= 0_06; P>0.05) while its relationship with milk yield was positive and significant (rp= 0.40: P<0.001).