Date of Award

1996

Document Type

Thesis

Degree Name

Master of Science (MS)

Department

Environmental Science

First Advisor

Nawal A. Ahmed

Second Advisor

Mohamed B . Abo ul-Ela .

Third Advisor

Mohamed K. Yousef

Abstract

The aim of the study was to compare some physiological and biochemical responses in camels, sheep and goats when subjected to various periods of food and water deprivation. Another purpose of the study was to examine the feeding and drinking behaviour of dehydrated and starved animals when provided with food and water simultaneously. The study was performed at the Faculty of Agricultural Sciences Farm, University of United Arab Emirates, Al-Ain.

Animals were deprived of water and food for various periods; feed and water were withheld 2, 4 or 6 days in camels and 1, 2 or 3 days for sheep and goats.

Measurements were made during the deprivation periods as well as after refeeding for 4 days. These measurements included: body weight, food and water consumption post starvation and dehydration, blood cell count, packed cell volume value and plasma biochemistry (Total protein, Albumin, Globulin, Blood urea nitrogen, Sodium, Potassium, Chloride and Index of osmotic pressure).

Results indicated that body weight decreased progressively with\ prolongation of the deprivation period in all three species. Preference for first eating or drinking after the various periods of fasting was influenced primarily by the duration of fasting. As the duration increased all species tended to drink first, when both feed and water were made freely available simultaneously. Also, it was observed that, the length of time spent in drinking within the first 15 min. of refeeding increased with prolongation of the fasting period for all species due to high level of dehydration, and thus increased osmotic pressure of blood.

After the deprivation period, all examined species consumed a higher amount of water than that consumed on the control day. Consumption, however, was increased progressively with the prolongation of the deprivation period. Roughage intake on the first refeeding day decreased as the period of fasting increased in all species.

Rectal temperature, percent changes in plasma volume and glucose concentration were lower during the fasting period in all species than during control or refeeding days, while no particular trend was found for white blood cells and potassium. However, in the three species studied there was a general trend of increased packed cell volume, total protein, albumin, globulin, blood urea nitrogen, sodium, Na/K ratio, chloride and index of osmotic pressure during the deprivation period compared to the respective pre-fasting (control) values, and these values decreased again after refeeding. Marked changes in RBCs shape and size were observed with fasting, particularly in goats.

Within four days after refeeding and rehydration animals of the three species regained their body weight losses and retained normal levels of most of their blood biochemical parameters.

In general, the data indicate that camels tolerate greater levels of dehydration and starvation than sheep and goats.

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