ResearchPad - wildlife-science https://www.researchpad.co Default RSS Feed en-us © 2020 Newgen KnowledgeWorks <![CDATA[Examining multiple paternity in the raccoon dog (<i>Nyctereutes procyonoides</i>) in Japan using microsatellite analysis]]> https://www.researchpad.co/article/Nb2d4311e-dd92-4083-85c5-7e9ee0f2d7f9 We analyzed the genotypes of three pregnant females and their litters to investigate the phenomenon of multiple paternity in wild raccoon dogs (Nyctereutes procyonoides) using 17 microsatellite markers. If a female has mated with only one male during estrus, then the maximum number of paternal alleles will not exceed two among littermates with the same father. The results revealed two out of three litters had three or four paternal alleles at one or five microsatellite loci. Therefore, the female had mated with more than one male during estrus. To the best of our knowledge, the present study is the first to report the possibility of multiple paternity in wild raccoon dogs.

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<![CDATA[Endoscopy gender determination and reproductive hormone profiles of Painted Terrapins (<i>Batagur borneoensis</i>) subjected to <i>ex situ</i> incubation]]> https://www.researchpad.co/article/Naef324a9-2efa-436a-a008-fe6479cb2528 Chelonian exhibit temperature dependent sex determination, and ex situ incubation of eggs in conservation hatcheries may render a gender bias. The gender of juvenile Painted terrapins (Batagur borneoensis) produced at a conservation hatchery in Malaysia was determined by endoscopy of the gonads. Circulating reproductive hormones (testosterone, progesterone and estradiol) were profiled for 31 juveniles and nine captive-reared non-breeding adult terrapins. Endoscopy revealed a gender bias of 96.8% (30/31) females. Testosterone levels in the juvenile females (2.49 ± 1.29) were significantly lower than that of the adult females (12.20 ± 4.29), and lower than values in the juvenile male (9.36) and adult males (27.60, 35.62). The progesterone levels in the juvenile females (107.12 ± 68.68) were significantly higher than that of the adult females (51.13 ± 24.67), but lower than values in the juvenile male (33.27) and adult males (3.43, 8.51). Estrogen levels were significantly lower in the juvenile females (1.57 ± 1.35) compared to the adult females (77.46 ± 53.45). Negative correlations were observed between levels of progesterone and testosterone, and progesterone and estrogen. A positive correlation was noted between estrogen and testosterone. The present study constitutes the first attempt to determine the gender and reproductive hormone profiles of juvenile Painted terrapins produced by ex situ incubation, and captive non-breeding adults. Endoscopy of the gonads is a useful techniques for gender determination among juvenile turtles, while the use of testosterone as a gender biomarker warrants further investigation.

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<![CDATA[Decreased genetic diversity in Kiso horses revealed through annual microsatellite genotyping]]> https://www.researchpad.co/article/N1baf5188-2f3e-4004-b5b3-70d58714f232 The Kiso horse is native to Japan and is on the verge of extinction. Here, we used microsatellites to characterize changes in their genetic diversity over time. We divided a population of Kiso horses that genotyped during 2007–2017 into three groups based on birth year: Group 1, 1980–1998 (70 horses); Group 2, 1999–2007 (61 horses); and Group 3, 2008–2017 (42 horses). We genotyped 31 microsatellites to calculate average number of alleles, observed heterozygosity, and expected heterozygosity. All indicators decreased across age groups. The results indicate that Kiso horses have been experiencing a drop in genetic diversity, and the population is expected to experience further decline unless appropriate measures are implemented.

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<![CDATA[Serologic survey of Brucella infection in cetaceans inhabiting along the coast of Japan]]> https://www.researchpad.co/article/Ned14dd3b-4ab2-430c-9b0b-fa26e93d9270

A serologic investigation of Brucella infection was performed in 7 species of cetaceans inhabiting along the coast of Japan. A total of 32 serum samples were examined by enzyme-linked immunosorbent assay (ELISA) using Brucella abortus and B. canis antigens. One serum sample from five melon-headed whales (Peponocephala electra) was positive for B. abortus. No serum sample showed positive for B. canis. The ELISA-positive melon-headed whale serum demonstrated a strong band appearance only against B. abortus antigens in Western blot analysis. Many detected bands were discrete, while some of them had a smeared appearance. The present results indicate that Brucella infection occurred in melon-headed whale population and the bacterial antigenicity is more similar to that of B. abortus than B. canis.

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<![CDATA[Evaluation of somatotype in the reticulated giraffe (<i>Giraffa camelopardalis reticulata</i>) using three-dimensional laser measurement]]> https://www.researchpad.co/article/5c11fc4dd5eed0c48483c0ba

The giraffe (Giraffa camelopardalis) is a difficult animal to keep in captivity as it has high mortality due to nutrition-related disorders, perhaps because the giraffe’s condition is difficult to evaluate. Image analysis techniques have recently become popular and may be useful for evaluating the giraffe’s somatotype. The present study aimed to evaluate the giraffe somatotype using a three-dimensional laser measurement device, and to examine the usefulness of this method. First, ten zoo staff members visually evaluated the somatotypes of three giraffes housed at Kanazawa Zoological Gardens, Japan. Next, three-dimensional point cloud datasets were obtained from these giraffes using the device. The point cloud datasets indicated that the cross-sectional area and width of the largest giraffe’s body were large in the abdominal region in the transverse sections. However, by visual examination, the ten zoo staff members deemed a different giraffe to be the largest. These results indicated that the three-dimensional laser measurement device could be used to evaluate giraffe somatotype in detail, and that this method may be an alternative to visual evaluation.

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<![CDATA[Population structure of the raccoon dog (<i>Nyctereutes procyonoides</i>) using microsatellite loci analysis in South Korea: Implications for disease management]]> https://www.researchpad.co/article/5c11fc4fd5eed0c48483c0cb

The prevention and control of infectious diseases transmitted by wildlife are gaining importance. To establish effective management strategies, it is essential to understand the population structure of animals. Raccoon dogs (Nyctereutes procyonoides) in South Korea play a key role in the maintenance of food web stability and possess genetic compositions that are unique compared to those in other areas. However, wild raccoon dogs play another role as the main host of various infectious diseases. To establish long-term strategies for disease management, we investigated the genetic structure and possible geographic barriers that influence the raccoon dog population in South Korea by analyzing 16 microsatellite loci. The present study showed that mountains were the major factors responsible for genetic structuring, along with distance. We proposed potential management units (MUs) for raccoon dogs based on the genetic structuring and gene-flow barrier data obtained in this study. Four MUs were suggested for the Korean raccoon dog population (Northern, Central, Southwestern, and Southeastern). The Korean raccoon dog population structure determined in this study and the proposed MUs will be helpful to establish pragmatic strategies for managing Korean raccoon dog population and for preventing the transmission of infectious diseases.

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<![CDATA[Ultrasonographic evaluation of the renal dimensions in captive tigers]]> https://www.researchpad.co/article/5bd406bfd5eed0c48477d34e

Ultrasonographic measurements of kidney size are useful in the practical diagnosis of kidney diseases in animals. In tigers, there is a lack of information regarding the ultrasonography methods used to measure the kidney size of the tiger. Thirty-three healthy captive tigers (Panthera tigris) were placed in lateral recumbency for ultrasonography. The measurements obtained from the ultrasonography were computed, and the results showed that there was a statistically significant difference between genders in terms of body weight and renal length. The length of the right kidney was significantly different from that of the left kidney (10.23 ± 0.76 cm in males versus 9.94 ± 0.80 cm in females; P<0.05). Interestingly, this study demonstrated that kidney length was statistically significantly associated with the body weight, and it also had a positive linear relationship with the body weight. Therefore, ultrasonographic renal dimensions could prove to be beneficial and modality for use in the evaluation of kidneys in unconscious tigers. However, kidney size evaluation must be performed using not only ultrasound but other clinical forms of technology and parameters.

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<![CDATA[Annual ovarian activity monitored by the noninvasive measurement of fecal concentrations of progesterone and 17β-estradiol metabolites in rusa deer (Rusa timorensis)]]> https://www.researchpad.co/article/5bd406c7d5eed0c48477d73c

To clarify the reproductive cycle of female Rusa deer (Rusa timorensis), the fecal concentrations of progesterone and 17β-estradiol metabolites were measured. Fecal samples were collected on a weekly basis for one year (between October, 2012 and September, 2013) from five healthy adult hinds in Thailand. At the beginning of the study, three hinds were pregnant. Two hinds delivered one healthy offspring, and one hind delivered a stillborn calf. The mating period of Rusa hinds in Thailand is from November to April. In pregnant hinds, fecal progesterone metabolite concentration was high in late pregnancy and abruptly declined to the baseline around parturition, suggesting that the placenta secretes a large amount of progesterone. Fecal 17β-estradiol metabolite concentration remained elevated around the day of parturition. Both concentrations of fecal progesterone and 17β-estradiol metabolites in non-lactating hinds were significantly higher than those in lactating hinds, indicating that ovarian activity of lactating hinds is suppressed by the suckling stimulus of fawn during lactation. The present study demonstrated that monitoring of fecal steroid hormones is useful method for assessing ovarian function in this species.

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<![CDATA[Histopathological findings in wild Nutrias (Myocastor coypus) with Capillaria hepatica infection]]> https://www.researchpad.co/article/5bd406e0d5eed0c48477e36c

Capillaria hepatica is a zoonotic nematode that uses rodents and other mammals as hosts, especially rats and mice, and causes hepatic granuloma and eventually fibrosis/cirrhosis. However, C. hepatica infection in nutria, a large semiaquatic rodent, has rarely been reported, and histopathologic features of the infection have not been described in detail. We conducted necropsy on 36 wild nutrias. Some animals were found to have milky spots, parasitic eggs and worms within hepatic microgranuloma involving central calcification with cell debris, macrophages, eosinophils and multinucleated giant cells (MGCs). Interestingly, the eggs were closely surrounded by MGCs and appeared to be destroyed without inducing further chronic changes. Based on microscopical examination, C. hepatica infection was diagnosed, and we describe its histopathological characteristics in wild nutrias.

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<![CDATA[Establishment of an on-site diagnostic procedure for detection of orf virus from oral lesions of Japanese serows (Capricornis crispus) by loop-mediated isothermal amplification]]> https://www.researchpad.co/article/5bd406d6d5eed0c48477dec6

Orf virus infection has been prevalent continuously in the population of wild Japanese serows (Capricornis crispus), goat-like grazing cloven-hoofed mammal species that live mainly in mountainous areas of Japan. Currently, definitive diagnosis of infection requires time-consuming laboratory work. To diagnose rapidly on-site, we developed a field-friendly procedure for the detection of orf virus from oral cavity lesions. DNA was extracted from goat saliva spiked with orf virus as a proxy for Japanese serows by a commercial kit without the use of electricity, and the quality of the extracted DNA was evaluated by conventional polymerase chain reaction (PCR). Extracted DNA was amenable to DNA amplification, the same as when extracted in a laboratory. Next, to find optimal conditions for DNA amplification by loop-mediated isothermal amplification (LAMP), Bst and Csa DNA polymerases and 3 colorimetric indicators for visual diagnosis, hydroxy naphthol blue (HNB), malachite green and D-QUICK, were compared using a portable cordless incubator. The combination of Bst or Csa DNA polymerase with HNB was found to be easiest for visual diagnosis by the naked eye, and viral DNA was successfully amplified from all orf virus strains used. These results suggest that the procedure established here can work completely on-site and can be useful for definitive diagnosis and differentiation of orf virus infection in Japanese serows in remote mountainous areas.

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