Welsh G W, Bunch T D
J Wildl Dis. 1983 Oct;19(4):342-4. doi: 10.7589/0090-3558-19.4.342.
Scabies due to infestation by Psoroptes ovis was monitored from 1979 through 1981 in Nelson's desert bighorn sheep in northwestern Arizona. Visual examinations for ear lesions and evaluations of ear scrapings were used to assess the prevalence of mites in sheep that were live-captured or killed during the hunting season. The prevalence of psoroptic scabies in live-captured sheep for the years 1979, 1980, and 1981, was 25%, 25%, and 0%, respectively, and was higher in rams (1979, 65%; 1980, 100%) than in ewes (1979, 11%; 1980, 0%). The severity of ear lesions was also greater in the males. The prevalence in harvested rams was 23%, 44%, and 7%, respectively, for the years 1979-1981. The severity of the ear lesions was highest in 1980. Lesions were confined to the ears. An aerial census of bighorns in the Black Mountains during May of 1981 showed a 38% decrease in total observations from the previous year and a drop in the ewe/lamb ratio from 0.52 in 1980 to 0.29 (P less than or equal to 0.01) in 1981. In the Lake Mead area, there was a population census decline of 33% in 1981 and a non-significant decline in the ewe/lamb ratio from 0.46 to 0.40. The population decline in 1981 and the increased prevalence and severity of psoroptic scabies in the 1980 survey in both areas were believed to be related to the high bighorn population densities in 1980 and the prevailing drought.
1979年至1981年期间，对亚利桑那州西北部尼尔森沙漠大角羊中由绵羊痒螨侵扰引起的疥癣进行了监测。通过肉眼检查耳部病变以及对耳部刮片进行评估，来评估在狩猎季节活捉或捕杀的绵羊中螨虫的感染率。1979年、1980年和1981年活捉绵羊中绵羊疥癣的感染率分别为25%、25%和0%，公羊的感染率（1979年为65%；1980年为100%）高于母羊（1979年为11%；1980年为0%）。雄性耳部病变的严重程度也更高。1979 - 1981年期间，被捕杀公羊的感染率分别为23%、44%和7%。耳部病变的严重程度在1980年最高。病变仅限于耳部。1981年5月对黑山地区大角羊进行的空中普查显示，总观测数比上一年减少了38%，母羊/羔羊比例从1980年的0.52降至1981年的0.29（P≤0.01）。在米德湖地区，1981年种群普查数量下降了33%，母羊/羔羊比例从0.46降至0.40，下降不显著。1981年的种群数量下降以及1980年调查中两个地区绵羊疥癣感染率和严重程度的增加被认为与1980年大角羊的高种群密度以及当时盛行的干旱有关。
