Exposure of experimental or wild animals to dioxins affects their thyroid function and morphology. In the present study, we studied the effect of dioxins on the thyroid gland of the wild Japanese monkey (Macaca fuscata). These monkeys live around human habitats and are taxonomically close to humans. Concentrations of dioxins and related compounds, such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (Co-PCBs), were measured in the adipose tissues, liver, and skeletal muscles. Thyroid glands of the same specimens were used for histopathologic analysis and quantitative evaluation of follicular cell hypertrophy by digital image analysis. Each concentration of PCDDs, PCDFs, and Co-PCBs ranged from 0.2 to 26pgTEQ/g-fat. There was no relationship between histopathological changes in thyroid gland and TEQ levels. Moreover, no significant alterations were found in the number of follicles or the size of follicular epithelial cells associated with TEQ levels. We concluded that though wild Japanese monkeys were exposed to dioxins and related compounds in the environment, the observed levels might not affect the morphology and function of the thyroid glands.

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Two hundred and fifty-four injured and diseased wild birds of 30 species were pathologically examined at the Shiga Prefectural Livestock Hygiene Service Center between February and April, 2004. The most common findings were trauma (138 ; 54.30%), followed by nontraumatic hemorrhage of internal organ (35 ; 13.8%), infection (26 ; 10.2%), nutritional disorder (24 ; 9.4%) and disorder of lymphoid tissue (1 ; 0.4%). Another 30 (11.8%) had no significant lesions and 46 (18.1%) were unfit for examination because of deterioration. The causes of death which were determined for 143 (56.3%) birds consisted of traumatic accident (135 ; 53.1%), infectious disease (5 ; 2.0%), and nutritional disorder (3 ; 1.2%). Pathogens in 26 birds were parasites (13 ; 50.0%), bacteria (9 ; 34.6%), mixture of parasites and bacteria (3 ; 11.5%) and fungi (1 ; 3.8%). Five birds were confirmed have died from the infectious diseases and these were tuberculosis-like granuloma, gizzard ulcer with a number of nematodes in submucosa, necrotic enteritis, purulent inflammation in the air spaces of the cranial bones, and deep mycosis caused by Aspergillus-like-fungi. Neither avian influenza virus nor Newcastle disease virus were isolated from 184 birds. This survey suggest that most of injured and diseased wild birds occurr when they encounter human habitatition, and they have infectious pathogens with high rate. For further study, the monitoring on a routine basis is important.

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The purpose of the present study was to determine patterns of fecal immunoreactive progestins (progesterone, iP_4 and pregnanediol-glucuronide, iPdG) and estrogens (estradiol-17β, iE_2 and estrone, iE_1), and to investigate the reproductive status and ovarian cycle of female Sumatran orangutans, Pongo abelii (n=2). In two females, menstruation lasted for 3.0±0.3 days (mean±SEM, n=17), and the menstrual cycle was 27.3±0.4 days (n=15 cycles). The ovarian cycle based on fecal iPdG profiles was 27.1±1.3 days (n=15 cycles), and based on fecal iE_2 profiles it was 26.8±2.4 days (n=17 cycles). Fecal iP_4 and iE_1 did not show cyclic changes during the non-pregnant stage. In the pregnant female, fecal levels of iP_4, iPdG, iE_2 and iE_1 during second half of pregnancy were significantly higher than those during non-pregnancy. These results suggest that fecal iPdG and iE_2 analyses are useful to demonstrate the ovarian cycle in Sumatran orangutans and their pregnancy could be diagnosed by any one of fecal iP_4, iPdG, iE_2 and iE_1 analyses.

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The Japanese serow (Capricornis crispus) is designated as a special natural treasure in Japan, but its genetic information has not been known in detail. In this study, we collected blood samples from Japanese serows in the Morioka City outskirts, and analyzed the serum protein polymorphism (albumin and transferrin) by polyacrylamide gel electrophoresis (PAGE) using commercial ready-made gel. As a result, we found that the albumin and transferrin domain had two types (Type A and B) and six types (Type I〜VI), respectively. Therefore, it was suggested that this method is efficient and useful for genetic analysis of Japanese serows.

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Fecal concentrations of progesterone (P_4), estradiol-17β (E_2) and testosterone (T) were measured and daily behaviors were recorded in a pair of Sumatran tigers. The fecal P_4 profile of the female indicated cyclic changes, and the cycle length was 58.3±2.7 days. The copulation interval was 58.0±4.0 days. When fecal P_4 contents were low and began to increase, the female's flehmen and exhibiting the tail area to the male were observed. Fecal E_2 contents in the female and T contents in the male tended to be high around the time when copulation was seen, but not always ; however, the male responded to the female estrous signs by vocalization, flehmen, chasing, mounting and copulation. It is possible to assess non-invasively reproductive activities by monitoring fecal P_4 concentrations in the female and the sexual behaviors of male and female Sumatran tigers.

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A multicentric squamous cell carcinoma was found in the oral cavity of an adult female Franc ois's leaf-monkey (Trachypithecus francoisi francoisi). The monkey showed apparent swelling of the facial region, and physical examinations revealed gingival swelling and osteolysis of both the mandible and maxillary region. Incisor regions of the maxillary and mandibular bones were replaced by neoplastic tissue, and a white nodule was found on the right cervical lymph node. Histopathological examinations revealed that the neoplasm was composed of multiple variably-sized islands of malignant neoplastic squamous epithelial cells with metastasis to the right cervical lymph node. This is the first report of oral squamous cell carcinoma in a leaf-monkey reared at a Japanese zoo.

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Invasive carcinoma of the mammary gland with systemic metastases was found in a captive nulliparous female California sea lion, over 17 years old. Numerous yellowish white masses of various sizes were discovered in the mammary region and many organs. Microscopically, all the masses consisted of epithelial tumor cells that were irregular in size and shape. Epithelial tumor cells had often invaded adjacent tissues and vessels, especially lymphatics. The tumor cells were arranged mainly in tubular to papillary formations with some solid sheets in the mammary region, whereas principally solid formations were found in the metastatic regions. We diagnosed this as a case of simple tubulopapillary to solid carcinoma of mammary gland with systemic metastases.

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