Effects of dehydration, rehydration, and hyperhydration in the lactating and non-lactating black Moroccan goat.
The effects of water deprivation, rehydration and hyperhydration were investigated in the black Moroccan goat (Capra hircus). Mean daily water intake was 46 +/- 5 ml/kg in lactating and 36 +/- 4 ml/kg in non-lactating black Moroccan goats, and milk production 21 +/- 1 ml/kg. Mean urine excretion was 8 +/- 2 ml/kg body weight in both groups, and the daily water losses via evaporation and feces were estimated at 23 +/- 3 ml/kg during lactation and 28 +/- 4 ml/kg during non-lactation. Forty-eight hours of water deprivation caused a body weight loss of 9% and 6% in lactating and non-lactating goats, respectively, and a drop of 28% in milk production with only a slight decrease in food intake. After rehydration, the elevated plasma osmolality as well as Na and total protein concentrations returned to basal values within 2-3 hr, indicating a rapid absorption of the ingested water, but urine excretion did not increase. After hyperhydration (10% of body weight), 46% of the load was excreted by the kidneys within 6 hr. In conclusion, black Moroccan goats have a low water turnover, and they can retain water upon rehydration but not store excess water after hyperhydration.
Hossaini-Hilali
J
J
Department of Physiology and Therapeutics, Hassan II Agronomic and Veterinary Institute, Rabat, Morocco.
Benlamlih
S
S
Dahlborn
K
K
D000450:Aldosterone / Q000097:blood; D000818:Animals; D001798:Blood Proteins / Q000032:analysis; D001835:Body Weight; D003681:Dehydration / Q000503:physiopathology*; D004231:Diuresis; D004326:Drinking; D004435:Eating; D004573:Electrolytes / Q000097:blood; D005260:Female; D006041:Goats / Q000502:physiology*; D007774:Lactation; D008892:Milk / Q000737:chemistry; D009994:Osmolar Concentration; D012417:Rumen; D014556:Urine / Q000737:chemistry; D014867:Water / Q000008:administration & dosage; D014868:Water Deprivation / Q000502:physiology*
D001798:Blood Proteins; D004573:Electrolytes; D014867:Water; D000450:Aldosterone