Japanese encephalitis on Saipan: a survey of suspected mosquito vectors.

An outbreak of Japanese encephalitis (JE) occurred on Saipan, Commonwealth of Northern Mariana Islands, in October 1990. Adult and larval mosquitoes were collected during September-October 1991 to retrospectively determine the probable mosquito vector(s). Virus was not isolated from 119 mosquito pools composed of 7,250 adult specimens as follows: Aedes vexans nocturnis (14%), Culex tritaeniorhynchus (39%), Cx. sitiens group (11%), Culex (Culex) species (35%), and < 1% each of Ae. albopictus, Ae. oakleyi, Aedes saipanensis, Cx. annulirostris marianae, and Cx. fuscanus. Three additional species were collected only as larvae: Anopheles indefinitus, Ae. neopandani, and Cx. quinquefasciatus. Among the vectors of JE incriminated in other areas, Cx. tritaeniorhynchus was the predominant species in our collections and the principal species feeding on swine. This is the first published record of the occurrence of this species on Saipan. Culex tritaeniorhynchus is abundant and widely distributed on the southern half of Saipan where human JE cases occurred in 1990, and where swine seroconversions were detected. Although the identity of the mosquito vector(s) responsible for the 1990 outbreak cannot be established with certainty, our results suggest that Cx. tritaeniorhychus was probably involved.

Avaliação da produção lacrimal, pressão intraocular, retinografia e biometria ocular em bovinos das raças Nelore e Gir hígidos / Evaluation of tear production, intraocular pressure, retinography and ocular biometry in bovine Nelore and Gir breeds

No presente estudo, foram avaliados parâmetros oftalmológicos de 38 bovinos das raças Nelore (n= 19; grupo GN) e Gir (n= 19; grupo GG), machos, com idade média de 15 meses. Os exames oftalmológicos realizados foram teste lacrimal de Schirmer 1 (TLS-1), tonometria de aplanação, retinografia e biometria por ultrassonografia em modo B. Os resultados do TLS-1, tonometria de aplanação e biometria ocular foram avaliados por meio da análise de variância (ANOVA), e as médias comparadas pelo teste de Tukey. Para o exame de retinografia, foi realizada a análise descritiva das estruturas anatômicas. O TLS-1 e a tonometria não diferiram (P≥0,05) nas comparações entre os olhos e entre os grupos raciais. A retinografia permitiu a visualização do disco óptico, dos vasos retinianos, do fundo tapetal e não tapetal, sem constatação de diferenças anatômicas entre as raças. Por meio da biometria ocular, foram observados valores maiores nos animais da raça Gir para as medidas do comprimento axial (CAx), da espessura da lente (EL) e da profundidade da câmara vítrea (CV), em ambos os eixos, horizontal (CAH) e vertical (CAV). Os exames oftalmológicos realizados podem ser executados a campo sem comprometer o bem-estar dos animais. Somente na ultrassonografia em modo B foram identificadas diferenças entre os bovinos das raças Nelore e Gir.(AU)

The ophthalmological parameters were evaluated of 38 male Nelore bovine (n= 19, GN group) and Gir (n= 19, GG group), with 15 months age. The ophthalmological examinations by Schirmer 1 (TLS-1), aplanation tonometry, retinography and B-mode ultrasonography were done. The results of the TLS-1, aplanation tonometry and ocular biometry were evaluated by analysis of variance and means compared by the Tukey test. A descriptive analysis of the anatomical structures was performed for the retinography examination. TLS-1 and tonometry did not differ (P≥ 0.05) in the comparisons between the eyes and between the groups. Retinography allowed the visualization of the optic disc, retinal vessels, tapetal and non-tapetal fundus, without any anatomical differences between the breed. In the ocular biometry, higher values were observed in Gir animals for measurements of axial length (CAx), lens thickness (EL) and depth of the vitreous chamber (CV), both horizontal (CAH) and vertical (CAV) imaging planes. Ophthalmologic examinations can be performed on the field without compromising animal welfare. Differences between Nelore and Gir bovines were identified only by B-mode ultrasonography.(AU)