SEASONAL CHANGES IN SOME COAT TRAITS OF GROWING DROMEDARY CAMELS UNDER EGYPTIAN SEMI-ARID CONDITIONS

Abstract

solar radiation (W/m 2 ) were recorded daily and the seasonal averages of these parameters were calculated. The lowest fiber diameter was observed in winter (48.5±0.5 µm), while the highest was in summer (63.7±0.5 µm). Medullation index followed the same seasonal trend (13.6±0.9 vs. 19.2±0.9, in winter and summer seasons, respectively). In contrast, staple length and coat depth were more in winter (2.80 ± 0.05 cm and 2.38±0.04 cm, respectively) than in summer (2.11±0.053 cm and 1.86±0.045 cm, respectively). There was a gradual increase in the percentage of the outer coat fibers from winter (16.03 ± 4.28 %) to summer (37.50 ± 4.28 %) versus a gradual decrease in the percentage of inner coat fibers (83.97 ± 4.28 to 62.50 ± 4.28 % in winter and summer, respectively). Ambient temperature correlated (p<0.01) with fiber diameter (r=0.71), coarse fiber percentage (r=0.47) and medullation index (r=0.54). Correlation coefficient between solar radiation and fiber diameter was (r= 0.45, p<0.01) while that between relative humidity and fiber diameter was (r= -0.40, p<0.01). These results indicate to the conformity between the seasonal climatic changes and camel coat traits to ensure the best adaptation the surrounding environmental condition