Mitochondrial DNA variation in the Japanese marten Martes melampus and Japanese sable, Martes zibellina

Genetic relationship among Japanese sables, Martes zibellina and the introduced Japanese martens, Martes melampus in northern Japan was revealed by analyzing a 521-524bp DNA sequence from the cytochrome b (112bp)/transfer RNA-threonine (67bp)/tRNA-proline (65bp) and control region (277-280bp) of the mitochondrial genome. Intraspecific differences in sequences of M. zibellina and M. melampus (3.8-15.0% and 1.9-16.4%, respectively) were similar to interspecific differences between these two species (5.8-16.6%). Comparison of sequence data exhibited five haplotypes of M. melampus and four haplotypes of M. zibellina, which clustered into two groups (clusters-A and-B). Cluster-A included two haplotypes of M. melampus and two haplotypes of M. zibellina, whereas cluster-B included three haplotypes of M. melampus and two haplotypes of M. zibellina. Results of this study lead three possible explanations. Firstly, past hybridization between M. zibellina and M. melampus might have occurred. Secondary, these two species might have similar heteroplasmy of mtDNA. Thirdly, these haplotypes might have come from nuclear genome. Although further intensive studies are needed to make a conclusion, detection of hybridization with the Japanese marten are occurred or not is quite important to conserve the Japanese sable.     

Focal fatty liver in a heifer: utility of ultrasonography in diagnosis

A 30-month-old Holstein heifer presented with a history of decreased appetite and respiratory signs. Sonographic examination of the liver incidentally revealed an area of increased echogenicity between the portal vein and the gallbladder. The lesion was nonspherical and had no mass effect or displacement of the adjacent vessels. Its boundaries, to the liver, were geographic. The liver specimen was histologically compatible with a diagnosis of focal fatty liver change (FFLC). The sonographic features of focal fatty infiltration of the liver are characteristic. Recognition of the ultrasonographic data is important to differentiate FFLC from other lesions.     

Immunohistochemical evaluation of canine ovarian cysts

To clarify the immunohistochemical characteristics of canine ovarian cysts, 109 canine ovarian cysts (57 cysts of subsurface epithelial structures: SES, 26 graafian follicle cysts, 12 cystic rete ovarii and 14 cysts difficult to classify morphologically) were examined regarding their lining cells immunohistochemically using antibodies against placental alkaline phosphatase (PLAP), S100, inhibin alpha, desmin and AE1/AE3. Both cysts of SES and cystic rete ovarii had a positive immunoreaction to desmin and AE1/AE3, whereas all cysts all but graafian follicle cysts were negative for inhibin alpha. PLAP-positive immunoreaction was observed only in cysts of SES. Graafian follicle cysts had a positive immunoreaction to inhibin alpha, but were negative for PLAP, desmin and AE1/AE3. Fourteen cysts were difficult to classify morphologically because these cysts had single-squamous lining cells and lacked other morphological characteristics. However, these unclassified cysts were immunohistochemically divided into two groups, including positive and negative cysts, by the reactivity of PLAP. The PLAP-positive cysts were considered large cysts of SES. These results suggest that PLAP was a useful marker for classification of cysts of SES, although cysts originating from SES are not always positive for this antigen.     

Systemic Mycobacteriosis in an Aborted Thoroughbred Fetus in Japan

A male Thoroughbred fetus was aborted on day 251 of pregnancy. Gross and histological examinations detected systemic granulomatous lesions in many superficial and visceral lymph nodes and organs including the liver, tonsils, lungs, thymus, spleen, right thyroid gland and gastrointestinal tract, and suppurative placentitis, pyogranulomatous amnionitis and intralesional acid-fast bacilli were also detected. An examination of the DNA base sequence of the β subunit of RNA polymerase demonstrated that Mycobacterium avium strain 104 had infected several organs. To the best of our knowledge, this is the first report of equine fetal mycobacterial infection in Japan.     

Expressions of protein oxidation markers, dityrosine and advanced oxidation protein products in Cisplatin-induced nephrotoxicity in rats

The purpose of this study was to evaluate whether dityrosine and advanced oxidation protein products (AOPP) reflect the severity of cisplatin-induced nephrotoxicity. Immunoexpression of dityrosine in kidneys and plasma AOPP concentration were examined up to day 4 post-cisplatin injection in rats. Cisplatin injection induced tubular injury on days 2-4 after injection and increased serum creatinine and BUN on days 3 and 4. On days 2-4, dityrosine was immunostained in the cytoplasm of damaged tubular cells, and their immunostaining intensity increased time-dependently. Plasma AOPP levels were significantly increased on days 3 and 4. These results suggest that expressions of dityrosine and AOPP were associated with the severity of renal injury and may be useful markers for the development of cisplatin-induced nephrotoxicity.     

Effects of bacterial strains on the development of the ripening flavor of cured pork loins

To determine the effect of bacteria on the development of the ripening flavor of cured meat, pork loins were cured with pickles containing 8 or 16% sodium chloride at 0 and 8°C. The bacterial flora, total free amino acid content and total free fatty acid content in the cured loins, sensory properties of cooked pork loins and the relationships between the proteolytic and lipolytic activities of isolates and curing conditions were investigated. Desirable bacteria, including salt‐tolerant bacteria and lactic acid bacteria, were predominant under the condition of 8% sodium chloride in the pickles and a curing temperature of 8°C. The total free amino acid content and total free fatty acid content at a curing temperature of 8°C were higher than those at 0°C. Cooked pork loins cured in pickles containing 8% sodium chloride at a temperature of 8°C for more than 7 days were preferred in terms of color, flavor and taste. Before the curing procedure, gram‐negative bacteria (Vibrio, Acinetobacter, Pseudomonas and Enterobacteriaceae) were predominant in the pork loins. During the curing period, the numbers of viable gram‐positive bacteria (Micrococcus, Staphylococcus and Pediococcus) increased and the numbers of viable gram‐negative bacteria decreased. Strains of Micrococcus and Staphylococcus with proteolytic and/or lipolytic activities in cured meat also increased during the curing period and were more predominant in the pork loins cured in pickles containing 8% sodium chloride and at a curing temperature of 8°C than in pork loins cured in pickles containing 16% sodium chloride and at a curing temperature of 0°C. The actions of these bacteria were thought to be important factors affecting the flavor of the cured pork. Micrococcus and Staphylococcus with proteolytic activity might contribute to the development of the ripening flavor of ham. The results of the present study together with the results of further investigations on the relationships of the enzyme activities of Micrococcus and Staphylococcus in cured meat with a preferable flavor would be useful for establishing a novel effective method for using bacteria to produce ham of a high quality.     

Estimation of nitrogen and phosphorus flows in livestock production in Dianchi Lake basin,China

We assessed the nitrogen (N) and phosphorus (P) flows in intensified livestock production systems by investigating nutrient budgets and cycling in the basin of Dianchi Lake, one of the most eutrophic lakes in China. We conducted field surveys based on feed samplings and interviews of livestock farmers. The N and P in local and external feeds, animal body retentions, animal products and excretions were calculated at the individual level for dairy cattle, fattening pigs, breeding sows, broilers and laying hens. The N and P flows in the total livestock production system in the area were estimated by multiplying the individual N and P budgets by the number of animals. For the dairy and fattening pig productions, N and P supplied from local crops or by‐products accounted for large parts of the inputs. For the other livestock categories, most of the N and P inputs depended on external resources. The N and P outputs through animal manure into the cropland were 287 and 66 kg/ha/year, respectively, which were higher than the N and P inputs into the livestock production systems from the cropland. The N and P loads from manure should be reduced for the establishment of sustainable agricultural production systems.