Submitted to: Latin American Association of Animal Production Seminar Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 11/1/2002
Publication Date: 11/1/2002
Citation: Interpretive Summary:
Technical Abstract: The impact of hair type on rectal temperature (RT), skin temperature (ST), respiration rate (RR), and feed intake under confinement in 3/4 Holstein 1/4 Senepol crossbred cattle was studied during summer of 2000 in Gainesville, Florida. The hair type was classified subjectively as 1) ("slick") very short, sleek and shiny and, 2) normal, similar to that of purebred Holstein cattle of the same age. The visual differences in hair coat were quantified using clipped samples. The samples were weighed, and slick animals averaged 0.55 mg/cm2 as opposed to 1.55 mg/cm2 for normal haired animals. The RT of animals classified as slick was 0.34 C (P<.05) lower than that from normal-haired animals. The ST of slick animals was 0.49 C (P<.05) lower than that of normal haired animals while the respiration rate of slick animals was 12.4 (P<.05) breaths per minute less than that of animals with normal hair. The impact of hair type on feed intake was not significant, perhaps because the animals where not fed under a high level of heat stress. The lower rectal temperatures of slick animals seem to be more evident under grazing conditions without shade or where the heat load levels are higher than those at the site of the experiment.