Digestibility Coefficients, Some Blood and Rumen Metabolites and Physiological Responses in Sudan Nubian Goats Subjected to Varying Levels of Feed and Water Restrictions

Abstract

Three yearling uncastrated males of Sudan Nubian goats
ranging in weight between 14 and 20 kg were used in a 3x3 latin square
design experiment with the objective of studying the effects of feed and
water restriction on dry matter intake (DMI), water intake, digestibility of
nutrients, rumen components, blood urea-N (BUN), rectal temperature
and respiration rate. The experiment consisted of three treatments:
Adlibitum feed and water, feed restricted to 50% of adlibitum level with
adlibitum water, water restricted to 50% of adlibitum level with adlibitum
feed. The results revealed no significant treatment effects on water intake,
urine volume, rectal temperature and respiration rate. However, DMI
differed significantly between treatments. The adlibitum provision of
water resulted in insignificant higher water intake compared with the
other two treatments. Rectal temperature was higher in water restricted
goats than in feed restricted goats, whereas respiration rate decreased
insignificantly with both feed and water restrictions. Feed and water
restrictions had no effect on the digestibility coefficients of the various
nutrients. Water restricted goats showed, however, different trends except
for ether extract digestibility which tended to decrease. Treatment had no
significant effect on the total digestible nutrients (TDN) values. The TDN
tended to be higher with water restriction. There was no significant
treatment effect on rumen pH, ammonia-N (NH3 -N) and BUN. Feed and
water shortage did not significantly affect digestibility of the proximate
components but tended to slightly affect rumen metabolites, BUN,
respiration rate and rectal temperature.