Seasonal Variations in Blood Constituents and Milk Composition of One-Humped Camel

Abstract

The present study has been conducted in order to investigate the seasonal variation as well as the effect of age and sex on certain blood constituents in the one-humped camels (Camelus dromedarius). Furthermore, the seasonal variation in the milk composition and the botanical and chemical composition of plant parts consumed by camels were investigated. The study has been conducted on 210 indigenous Arabian camel of different age (1-18 years) and sex, and kept under natural range in Southern Darfur. The data analysis revealed that the season had significant effects on some of the haematological indices, metabolites and mineral concentrations. These parameters showed slight variations related to age and sex. The red blood cells count, lymphocytes and basophils percentages increased significantly during the dry season, while the osmotic resistance, MCV, MCH and neutrophils percentage increased significantly during the green season. The serum levels of total protein, globulins and triglycerides increased significantly during the dry season, while the levels of plasma glucose, serum urea, creatinine, phosphorus (P) and calcium (Ca) increased significantly during the green season. The PCV, neutrophils percentage, serum total protein and serum Ca concentration increased significantly with age, while the lymphocytes percentage, serum P and serum sodium (Na) concentration decreased significantly with age. The red blood cells count and PCV level were the only investigated parameters that showed significant intersex differences. The levels of red blood cells count and PCV were significantly higher in males. The study showed that seasonal variation has a marked effect on milk composition. The percentages of milk moisture and fat increased significantly during the dry season, while lactose percentage increased significantly during the green season. The findings of the present study indicate that camels are selective browser rather than grazer. Furthermore, they are selective feeder to the parts of pasture plants they consume. The percentages of crude protein (CP), crude fibre (CF) and nitrogen free extract (NFE) of pasture plants selected by camels were significantly higher, while ash percentage was significantly lower during the dry season. The results obtained in the present study indicate that the nutritional state could induce significant changes in the physiological responses of the dromedary camel; the available forage during the green season improved the body condition, the blood metabolites and mineral profile of camels and the milk composition. The results indicate that despite camel’s selectivity and unique adaptation to arid conditions, glucose, urea, P and Ca levels were lower during the dry season. Therefore, it could be beneficial to provide concentrate feed to camels kept under dry tropical conditions.