Significance of Feeding Induced Hypovolemia in Feed Intake Control of Goats Fed on Alfalfa Hay

Sunagawa, Katsunori; Prasetiyono, Bambang Waluyo Hadi Eko; Nagamine, Itsuki

doi:10.5713/ajas.2002.366

Cited by 3 publications

(1 citation statement)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These results indicate that central receptors for plasma osmolality did not completely determine thirst levels in response to feeding because animals intraruminally infused with parotid saliva did not drink more water despite having a higher plasma osmolality than that in the noninfusion treatment. Sunagawa et al (2001Sunagawa et al ( , 2002a intravenously infused in goats fed alfalfa hay cubes twice a day with an iso-osmotic mannitol solution. The infusions were conducted from 1 h prior to feeding and continued until 1 h of a 2 h feeding period had elapsed.…”

Section: Discussionmentioning

confidence: 99%

Effect of Parotid Saliva Secretion on Dry Forage Intake in Goats

Sunagawa¹,

Nakatsu²,

Nishikubo³

et al. 2003

Asian Australas. J. Anim. Sci

Self Cite

View full text Add to dashboard Cite

Research was carried out to clarify whether a suppression of dry forage intake during the early stages of feeding in ruminants is caused by feeding induced hypovolemia which is produced by the accelerated secretion of parotid saliva. Goats with a parotid fistula were fed roughly crushed alfalfa hay cubes, commercial ground concentrate feed and NaHCO 3 twice daily (10:00-12:00, 16:00-18:00). The animals were free access to drinking water all day prior to, during and after experiments. The animals were intraruminally infused every day prior to the morning feeding period with parotid saliva collected from the parotid fistula over a 24 h period. The present experiment consisted of two treatments, non-infusion (RNI) and intraruminal infusion of parotid saliva (RSF). In the RSF treatment, 4-5 kg of parotid saliva (280-290 mOsm/l) collected over a 24 h period was intraruminally infused 1 h prior to the commencement of the morning feeding. During feeding, eating and parotid saliva secretion rates were measured. Blood samples were also periodically collected from the jugular vein. During and after 2 h feeding, water intakes were measured, respectively. These measurements were used to define thirst levels. It is thought that rumen fill in the RSF treatment was higher than the RNI treatment. Plasma osmolality in the RSF treatment increased in the first half of the 2 h feeding period due to the intraruminal infusion of parotid saliva. Therefore, parotid saliva secretion rates in the RSF treatment were lower than the RNI treatment for 30 min period from 30 to 60 min after the commencement of feeding. On the other hand, plasma total protein concentration and hematocrit in the RSF treatment decreased by 3.2 and 3.3% prior to the commencement of feeding due to the intraruminal infusion of parotid saliva. In the first half of the 2 h feeding period, plasma total protein concentration and hematocrit in the RSF treatment showed a tendency to decrease compared to the RNI treatment. Thirst level in the RSF treatment during feeding was approximately 31.3% less than the RNI treatment. Upon the completion of the 2 h feeding period, cumulative feed intake in the RSF treatment was significantly larger (19.7%) than the RNI treatment. The results suggest that a suppression of dry forage intake during the early stages of feeding in goats is partly caused by feeding induced hypovolemia, which is produced by the accelerated secretion of parotid saliva.

show abstract

Section: Discussionmentioning

confidence: 99%