SOME FACTORS AFFECTING THE WEIGHT GAIN OF GRAZING SHEEP IN PALU VALLEY’S RANGELANDS

Abstract

This study, lasted for 12 weeks, was conducted at 7 villages in Palu, 4 of which
were located in sub-district of East Palu while the other 3 were in that of South Palu.
The objective of the study was to examine factors that contributed to the live weight
changes of sheep grazing on the rangelands of those villages. The sheep to be involved in this study were initially screened from all the sheep owners found in the villages having at least 20 sheep per owner. Randomization was then performed in such a way to form 15 farmer groups with a total animal number of 300 (20 sheep per group) which were proportionally distributed in all villages. The 20 animals per group were divided into 2 sub groups (10 animals each) to receive either one of the following two treatments: supplementation with rice-bran (250 g/animal/d) or control (no supplementation). All the animals were treated for possible worm infestation (2 piperazine capsules/animal) before beginning the study. The rice-bran supplement was offered to the animals daily in the morning before they were allowed to graze normally. Intake ofthe supplement was recorded daily while changes ofthe animals’ body weight were measured weekly. An analysis of variance was applied to test effects of perceived contributing factors (animal genotype, animal sex, study site and rice-bran supplement) on body weight changes of the animals. At the end of the study, there were only 292 animals available for analysis; 8 animals were dead or sold by their owners. Results showed that the body weight gain of the sheep was significantly (P<0.05) affected by all the factors considered, except for the effect of animal genotype. However, these 4 factors shared only 24.0% contribution in affecting the animal weight gain (genotype 0.12%, sex 4.68%, rice-bran fed 7.12%, and village 11.99%). Body weight gain of the local fat-tailed sheep did not differ (P>0.05) to that of the crossed fat-tailed X merbas breed indicating a need to reconsider the cross breeding program on this indigenous local breed.