Survey on Mite Infestations in Small Ruminants in Kindo Didaye District, Wolaita zone, Southern Ethiopia

BACKGROUND

Mange is a parasitic skin disease caused by microscopic mites that feed on the skin of small ruminants and affect animal productivity.

METHODS

A study was carried out to determine the prevalence and possible risk factors for mite infestation in small ruminants in Kindo Didaye district, Wolaita zone, southern Ethiopia. Skin scraping samples were collected from 384 small ruminants (196 goats and 188 sheep) for the identification of mite species following the standard parasitological protocol.

RESULTS

Of the 384 examined animals, 6.25% of sheep and goats were infested with different mite species, namely, Sarcoptes (3.67%), Demodex (1.54%), and mixed infestation of Sarcoptes and Demodex (1.04%). A relatively higher prevalence of mite infestation occurred in goats (7.14%) than in sheep (5.3%), and the highest prevalence of lesions of mange mites was recorded in the neck region (3.13%). The multivariate analysis of factors revealed that only BCS and herd size have a significant role in mite infestation of small ruminants. In addition, the correlation analysis of mite infestation with factors revealed that herd size (r = .106), sex (.0434), and body condition score (r = .104) had a positive correlation with mite infestation.

CONCLUSION

Mites are among the most important health constraints of sheep and goats in the study area, requiring immediate attention and control interventions. Moreover, further epidemiological investigations that consider agroecology and other nonhost-related risk factors should be carried out for the appropriate control of mange mites.

Evaluation of Traits for the Selection of Apis Mellifera for Resistance against Varroa Destructor

Infestation with Varroa destructor is a serious cause of bee colony (Apis mellifera) losses on a global level. However, the presence of untreated survivor populations in many different regions supports the idea that selection for resistance can be successful. As colony survival is difficult or impossible to measure, differences in mite infestation levels and tests for specific behavioral traits are used for selective breeding for Varroa resistance. In this paper we looked into different definitions of mite infestation and linked these with brood hygiene (pin test), brood recapping and suppressed mite reproduction. We based our analyses on datasets of Apis mellifera carnica from three countries: Austria (147 records), Croatia (135) and Germany (207). We concluded that bee infestation in summer, adjusted for the level of natural mite fall in spring, is a suitable trait in the breeding objective, and also suggested including brood infestation rate and the increase rate of bee infestation in summer. Repeatability for bee infestation rate was about 0.55, for cells opened in pin test about 0.33, for recapping 0.35 and for suppressed mite reproduction (SMR) virtually zero. Although in most cases we observed correlations with the expected sign between infestation parameters and behavioral traits, the values were generally low (<0.2) and often not significantly different from zero.

Treatment of naturally acquired demodectic mange with amitraz in two harbour seals (Phoca vitulina)

Two male harbour seals (Phoca vitulina; 33 and 35 years old, respectively), housed since 2002 at a zoo for exhibition purposes, developed severe, multifocal and diffuse skin lesions. Skin scrapings and microscopy for parasites as well as pure cultures for bacteria and dermatophytes were carried out to identify the aetiological agent. Skin scrapings showed that lesions appearing on the seals were caused by an infestation of Demodex mites, which is uncommon in marine mammals, and were not due to other causative agents (parasites, bacteria or dermatophytes). Treatment with amitraz (0.01%) once a week for three weeks and with ampicillin (10 mg/kg SID per os) for six days eliminated the mites and resolved the clinical signs of demodectic mange in the harbour seals. The purpose of this report is to describe the successful treatment of naturally acquired demodectic mange with amitraz in harbour seals.

The first outbreak of Chorioptes texanus (Acari: Psoroptidae) infestation in a cattle farm in Korea

Mites in the genus Chorioptes cause a mild form of skin disease in both domestic and wild ruminants. In July 2006, dermatitis characterized by alopecia, marked lichenification, accumulation of crust, and fissuring was recognized in 14 out of 200 Holstein dairy cattle raised in the cattle farm of the National Institute of Animal Science in Cheonan, Republic of Korea. Skin lesions were distributed mainly over the tail base, and sacral and perineal regions. Microscopic examinations of skin scraping samples from severely affected areas revealed numerous mites of all developmental stages. Morphologically, pedicels of the mites were short and unjointed. The tarsal suckers occurred on the pedicels of all the legs in the male worm and on the first, second, and fourth pair of legs in the adult female worm. A single long seta at the tarsus of legs III and the length of legs II being about twice as long as legs IV in adult male mites were observed. Arising anterior to the inner-most spatulate seta was a short seta with an average of 26.4 +/- 5.8 microm in length. Also, the length of setae #4 on the opisthosomal lobes was relatively short. Based on these observations, the mites were identified as Choriptes texanus. Although the chorioptic mange may not influence the mortality rate in the affected farm, reports indicate that a decline in milk production can be observed. This is the first report of chorioptic infestation in a cattle farm from Korea.