Prevalence and intensity of Echinococcus multilocularis in red foxes (Vulpes vulpes schrencki) and raccoon dogs (Nyctereutes procyonoides albus) in Otaru City, Hokkaido, Japan

A survey was done in an attempt to investigate the epidemiological status of Echinococcus multilocularis in red foxes and raccoon dogs in Otaru city from June to September 1999. Sixty-seven red foxes (Vulpes vulpes schrencki) and 13 raccoon dogs (Nyctereutes procyonoides albus) were captured, and postmortem examinations were conducted with them. Thirty-eight red foxes (56.7%) and 3 raccoon dogs (23.1%) were found to be infected with E. multilocularis. The total biomass of E. multilocularis in all infected red foxes and raccoon dogs were 2,817,000 and 1,515 worms, respectively. Nine of the infected red foxes harboring more than 100,000 worms accounted for 90.6% of the total biomass. No significant differences in the prevalence were observed between male and female, and juvenile and adult. However, the worm burden was higher in juvenile than in adult foxes. In one of the infected raccoon dogs, mature worms and eggs of E. multilocularis were found in the intestine and fecal sample, respectively. This result suggested that the raccoon dogs are probably playing a small role in the egg contamination of the environment. The validity of coproantigen ELISA for diagnosis of foxes was confirmed by comparing the results of autopsy, egg examination and coproantigen ELISA using rectal fecal samples.     

Effects of rice conservation methods on lactation,blood metabolites,and rumen fermentation in dairy cows

We investigated the effect of rice grain conservation methods on feed intake, milk production, blood metabolites, and rumen fermentation in dairy cows. Raw rice grain was dried before crushing (DRY), ensiled after crushing (ENS‐A), or ensiled before crushing (ENS‐B). Twelve multiparous Holstein cows were used in a replicated 3 × 3 Latin square design with three dietary treatments comprising ad libitum access to one of three total mixed rations (TMRs; containing DRY, ENS‐A, or ENS‐B at 17% of dietary dry matter) plus a standard allowance of 2.0 kg/day of dairy concentrates. The dietary treatments did not affect the feed intake, milk yield, or milk composition. The selected blood constituents were not influenced by the rice conservation method. The ruminal lactic acid and total volatile fatty acid (VFA) concentrations and the VFA proportion in the cows were not influenced by the rice conservation method. These results demonstrate that the rice grain conservation method has little impact on lactation performance when cows are fed a TMR containing 17% treated rice grain (dry matter basis).     

Effects of the butyric acid‐producing strain Clostridium butyricum MIYAIRI 588 on broiler and piglet zootechnical performance and prevention of necrotic enteritis

The objective of this study was to assess the effects of a probiotic strain Clostridium butyricumMIYAIRI 588 (CBM588) on broiler and weaned piglet health and zootechnical performance. Five field studies were carried out in broilers and five in weaned piglets under European feed additive guidelines. Each study followed a randomized blocked design with two treatments: Control (basal diet) and CBM588 supplemented groups. The zootechnical performance parameters selected were body weight, daily gain, feed intake and feed efficiency (feed:gain). Broilers fed diets with CBM588 gained significantly more weight (+2%, p < .001) and exhibited significantly better feed efficiency (?1.6%, p < .001) in comparison with Controls. Similarly, analysis of pooled data of weaned piglet trials showed that CBM588‐fed piglets were significantly heavier than Controls (+2.6%, p = .014), exhibited significantly higher mean daily gain (+4.7%; p = .004), and significantly improved feed efficiency (?4.2%, p = .001). In addition to the zootechnical efficacy studies, the preventive effect of CBM588 on necrotic enteritis (NE) was assessed in a natural challenge model in broilers where CBM588 reduced the incidence and severity of NE lesions. These data indicate the potential of CBM588 to improve broiler and weaned piglet zootechnical performance, and to make a positive contribution to animal health.     

Gene organization and polymorphism of the swine major histocompatibility complex

The recent availability of the full‐length sequence of one haplotype of the swine leukocyte antigen (SLA) complex, the swine major histocompatibility complex (MHC), and significant progress in the studies on gene expression and polymorphisms led to major advances in deciphering its role in resistance to diseases in animals. The present status of the genomic organization and polymorphism of the SLA complex is presented in this Review. Additionally, a comparative analysis with mammalian MHC has also been provided. The sequenced SLA‐H01 haplotype harbors 152 loci including genuine SLA genes, non‐MHC genes and pseudogenes. Although the numbers of expressed SLA genes could vary across haplotypes, three SLA class Ia, three SLA class Ib, four SLA class IIa and four SLA class IIb genes are currently expressed. Except for the class I genes, which have no clear orthologs, the gene organization of the loci was highly conserved between humans and pigs. Moreover, the human leukocyte antigen (HLA) complex lies on a single chromosomal segment, whereas a centromere at the class II and III junction splits the SLA complex into two segments, without disturbing gene organization or impeding functionality. Over 400 SLA class I and II allele sequences available in databases have been recently clustered and assigned to a specific SLA locus according to a newly defined nomenclature system.     

Localized amyloidosis in canine mammary tumors

Histopathologic and immunohistochemical examinations were performed on localized amyloidosis associated with mammary tumors in two dogs. These tumors were identified as adenoma and adenocarcinoma. An acellular, amorphous pale eosinophilic material (amyloid) was observed in the lumina of acini lined by neoplastic cells and in the stroma of the tumors. Concentrically laminated pale eosinophilic bodies (corpora amylacea) were also found in the lumina of the acini. Amyloid and corpora amylacea stained positively with Congo red with and without 5% potassium permanganate pretreatment and revealed a green birefringence under polarized light. Corpora amylacea showed an occasional Maltese-cross pattern. Immunohistochemically, amyloid and corpora amylacea usually stained positively with anti-bovine alpha-casein antibody but negatively with anti-human amyloid AA, anti-bovine kappa-light and lambda-light chains, anti-human lactoferrin, anti-human transferrin, anti-human secretory component, and anti-human polyglucosan antibodies. These findings suggested that the amyloid deposition in these canine mammary tumors was related to lactating casein.