Performance of 1-year-old camel calves fed a basal ration of alfalfa hay supplemented with different levels of concentrate.

Background: The use of a high-concentrate diet in fattening camels may have significant effects on growth performance and digestion as well as economic returns. This experiment was designed to study the effects of feeding different levels of concentrate in their diet on growth performance and digestion in a desert climate.

Methods: Eighteen 12-month-old male camel calves were used, and divided into three treatments of six each. The concentrate was administered based on their body weight (BW) at 0.7 (low), 1.0 (medium), and 1.3% (high), with free access to alfalfa and water. The experiment lasted for 6 months, in which digestibility trials took place at 14, 16, and 18 months of age, which corresponded to 2, 4, and 6 months of the experimental period.

Results: No significant variations were observed in final BW, BW changes, or average daily gain among feeding treatments. Increasing the concentrate level had a negative effect on roughage intake, impacting the roughage-to-concentrate ratio (P < 0.05) and neutral detergent fiber digestibility (P < 0.05). Increasing concentrate levels significantly increased total intake (P < 0.05), leading to a worse feed conversion ratio (P < 0.05). However, animal age had no negative effect on nutrient digestibility, and there were no interactions between concentrate supplement level and animal age. Significant increases in plasma total protein (P < 0.05) and urea (P < 0.05) were observed when the leve lof concentrate was increased. A similar trend was observed in rumen ammonia concentration. Camel calves fed low vs. medium or high levels of concentrate showed a greater rumen pH (P < 0.05), which was linked to a lower concentration of volatile fatty acids (P < 0.010).

Conclusions: The present study concluded that yearling camel calves receiving different levels of concentrate with ad lib alfalfa hay could cover their nutrient requirements for maintenance and growth with a daily gain of 630 g/day when the level of concentrate was limited to 0.7% of BW and the total intake was only around 1.65% of BW, or 70.6 g/kg metabolic BW.