Nitrogen flow on an organically managed beef farm in Hokkaido,Japan

Nutrient recycling should be effective at balancing nutrient flows in Japanese animal production. This means replacing imported feed with self-produced feed. The Yakumo Experimental Farm of Kitasato University has produced commercial beef under ‘organic’ management, without the use of agricultural chemicals or imported feed, since 2005. Using a data set obtained from 220 ha of grassland and 250 head of cattle over the 5 years from 2008 to 2012, we estimated nitrogen (N) flow. During 2011 and 2012, we measured grass production, cattle production (selling out), soil parameters and atmospheric deposition (from precipitation and atmospheric ammonia concentrations). To determine N fixation by clover (white clover, Trifolium repens L.), we compared grass + clover plots with grass-only plots. Averaged over the period, N components on the 220 ha of grassland comprised 1952 Mg soil N stock, 3.2 Mg N yr^?1 in living livestock, 14.3 Mg N yr^?1 uptake by grass growth (including 8.6 Mg yr^?1 of N fixed by clover), 15.7 Mg N yr^?1 applied in composted manure, 1.7 Mg N yr^?1 in imported bedding material, 2.8 Mg N yr^?1 in deposition and 1.41 Mg N yr^?1 in meat production. N in composted manure equaled about 0.8% of the huge soil N stock; N in grass production equaled about 0.7%, of which clover fixation supplied 60%; N deposition was not negligible; and N export by meat production was minor. These results show that on this organically managed farm, soil N stock increased gradually (by 8.6 Mg N yr^?1 [220 ha]^?1 = 39 kg N ha^?1 yr^?1 = 0.02% of the soil N stock) and N export was small. Our findings show that it is possible to balance N inputs with N outputs in a beef cattle enterprise without the need for feed or fertilizer imports.     

Effects of continuous low-dose infusion of lipopolysaccharide on expression of E-selectin and intercellular adhesion molecule-1 messenger RNA and neutrophil accumulation in specific organs in dogs

OBJECTIVE: To determine the effects of continuous low-dose infusion of lipopolysaccharide (LPS) on the expression of E-selectin and intercellular adhesion molecule-1 (ICAM-1) mRNA and neutrophil accumulation in the lungs, liver, spleen, small intestine, and pancreas in dogs. ANIMALS: 11 healthy adult Beagles. PROCEDURE: Dogs received a continuous infusion of a low dose (10 microg/kg/h, i.v.) of LPS (Escherichia coli 055:B5) or saline (0.9% NaCI) solution (20 mL/kg/h, i.v.) for 8 hours. Activity levels of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and interleukin-6 (1L-6) and the number of WBCs in circulation were examined before and 1, 2, 4, and 8 hours after the onset of LPS infusion. Expression of E-selectin and ICAM-1 mRNA and the number of neutrophils in each tissue were examined. RESULTS: After the onset of LPS infusion, serum TNF-alpha and IL-1beta activities transiently increased. Thereafter, IL-6 activity increased, and high IL-6 activity was maintained throughout the experiment. In dogs in the LPS group, expression of E-selectin mRNA increased only in the lungs, and expression of ICAM-1 mRNA increased in the lungs and liver; the number of neutrophils in the tissue increased in the lungs and liver. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that expression of E-selectin and ICAM-1 mRNA increased during sepsis, particularly in the lungs and liver, and that this increase was associated with neutrophil accumulation. Hence, inhibiting the activation of endothelial cells in the lung and liver may decrease organ damage caused by accumulated neutrophils and help regulate multiple-organ dysfunction.     

Seroprevalence of Toxoplasma gondii in American free-ranging or captive pumas (Felis concolor) and bobcats (Lynx rufus)

Toxoplasma gondii is a major zoonotic agent infecting a wide range of mammals, including wild felids. Like domestic cats, wild felids are involved in the complete infective cycle of T. gondii, as they can host in their gastrointestinal tract sexually mature parasites and shed infective oocysts in their feces. In order to evaluate the importance of this wildlife reservoir, 438 serum samples collected between 1984 and 1999 from 438 pumas (Felis concolor) and from 58 bobcats (Lynx rufus) from North America, Central America and South America were screened for antibodies to T. gondii. The overall prevalence of T. gondii antibodies was 22.4% in pumas and 51.7% in bobcats, with regional variations. Adults were more likely to be seropositive than juveniles and kittens (prevalence ratio (PR) = 2.61; confidence interval (CI) = 1.15, 4.04). In the US, pumas from the southwestern states (Arizona, California and New Mexico) were more likely to be seropositive for T. gondii ( PR = 2.61; 95% CI = 1.32-5.18 ) than pumas from the northwestern and mountain states (Colorado, Idaho, Oregon, Utah and Wyoming). Male pumas from the US were more likely to be seropositive than females (PR = 2.08; 95% CI = 1.11-3.92), whereas female pumas from Mexico, Central America and South America were more likely to be seropositive than female pumas from Canada and the US (PR = 2.49; 95% CI = 1.09-5.69). Captive pumas were also more likely to be seropositive (21.7%, 29/92) for T. gondii than free-ranging animals (19.9%, 69/346) (PR = 1.85; 95% CI = 1.06, 3.17).     

Surgical correction of congenital lobar emphysema in a dog

Massive lobar emphysema in the middle lobe of the right lung was observed in a dog brought to our clinic with sudden onset of tension pneumothorax, and lobectomy was performed to excise it. Pathological examination resulted in a diagnosis of congenital bronchiectasis associated with bronchial cartilage hypoplasia. Two cases of diagnosis and successful treatment of congenital lobar emphysema have been reported in dogs.     

Ovarian teratoma with a formed lens and nonsuppurative inflammation in an old dog

A 9-year, 7-month-old female German shepherd weighing 26.6 kg was admitted to the hospital for pica and diarrhea. A large mass was found in the right ovary and removed, and cross section of the mass revealed a multilobular tumor consisting of several cystic cavities which contained tufts of dark hair in thick creamy-white sebaceous fluid. Histologically, the tumor consisted of adipose tissue, central nervous tissue, crystalline lens, cartilage and bone. In the central nervous tissue, lens and lesions like nonsuppurative inflammation comprizing of accumulation of glial cells and lymphocytic perivascular cuffing were observed. The tumor was diagnosed as a mature cystic teratoma.     

Phylogenetic analysis of the hemagglutinin (H) gene of canine distemper viruses isolated from wild masked palm civets (Paguma larvata)

Hemagglutinin (H) gene of two CDV isolates, the Haku93 and Haku00 strains, from masked palm civets was molecularly analyzed. H genes of both two CDVs contained one open reading frame encoding 607 amino acids. Nucleotide and predicted amino acid sequences of H gene of the CDV Haku93 and Haku00 revealed high similarity to those of recent field isolates such as the Yanaka and Tanu96, while they showed limited identity to those of old vaccine strains. Potential N-linked glycosylation sites in both Haku93 and Haku00 were identical to other recent CDV isolates. Phylogenetic analysis revealed that the CDV strains derived from masked palm civets were classified into the group of recent Japanese CDV isolates.     

Cryopreservation of bovine somatic cell nuclear-transferred blastocysts: effect of developmental stage

The effect of developmental stage on the survival of bovine somatic cell nuclear-transferred blastocysts after freezing and thawing was evaluated. We also investigated how freezing affects nuclear-transferred (NT) embryos and in vitro fertilized (IVF) bovine embryos. Advanced-stage bovine NT blastocysts survived freezing better than early-stage NT blastocysts (86 vs 14%). The trend was similar with IVF embryos (87 vs 30%). At the stages tested, there was no significant difference in the survivability of NT and IVF embryos from advanced (86 vs 87%) or early-stage blastocysts (14 vs 30%). The average survival rate did not differ between NT and IVF bovine embryos (50 vs 51%). The higher survival rate of advanced-stage blastocysts compared to early-stage blastocysts in NT and IVF bovine embryos might be due to their higher cell number. In NT (128 +/- 25 vs 53 +/- 20) and IVF (128 +/- 29 vs 75 +/- 22) groups, advanced-stage blastocysts contained a significantly higher total cell number than early-stage blastocysts. There was no difference in total cell number between advanced-stage NT and IVF blastocysts (128 +/- 25 vs 128 +/- 29), however, early-stage NT and IVF blastocysts (53 +/- 20 vs 75 +/- 22) differed significantly.     

Distribution of Arcobacter species among livestock in Japan

A survey was conducted to examine the distribution of Arcobacter species among livestock in Japan. During May 1999 and May 2000, fecal samples from cattle (n=332) and swine (n=250), chicken cloacal swabs (n=234), and vaginal swabs of cattle (n=61) and swine (n=15) were submitted for the isolation of Arcobacter species. Arcobacter species were isolated from 3.6 and 10.0% of the cattle and swine fecal samples, respectively, along with 14.5% of chicken cloacal swabs. No significant seasonal differences were observed. Species-specific polymerase chain reaction assay showed that A. butzleri was the most prevalent species (83.3, 60.0 and 47.1% of the cattle, swine and chicken isolates, respectively), followed by A. cryaerophilus 1B (16.7, 36.0 and 55.9% of the cattle, swine and chicken isolates, respectively). Of the samples from vaginal swabs, 8.1 and 13.3% were positive for Arcobacter in cattle and swine, respectively. This is the first report demonstrating the distribution of Arcobacter species among livestock in Japan.     

Development of a canine trypsin-like immunoreactivity assay system using monoclonal antibodies

The radioimmunoassay (RIA) for trypsin-like immunoreactivity (TLI) is one of the most sensitive and specific tests for detecting exocrine pancreatic insufficiency (EPI). An abnormally low serum TLI concentration (<2.5 ng/ml) indicates end-stage EPI. Although RIA methods can be used to detect canine serum TLI, these procedures are beyond the capabilities of most veterinary clinics and general laboratories. Using monoclonal antibodies (mAbs), we developed an enzyme-linked immunosorbent assay (ELISA) for canine TLI and incorporated it into an immunochromatographic test (ICT) for the diagnosis of EPI. The ELISA was linear over TLI concentrations of 1-100 ng/ml. Levels of intra-assay coefficients of variance (CVs) were 1.8-6.1%, inter-assay CVs were 5.1-9.8%, and the recovery of TLI added to two samples of canine serum ranged from 89 to 111 and 93 to 108%, respectively. Good correlation (correlation coefficient, 0.974) occurred between the TLI values obtained by the ELISA method and those by RIA from 56 clinical samples. Serum TLI values in clinically healthy dogs ranged from 7.8 to 29.2 ng/ml by ELISA, and those from dogs with EPI were 0.0-0.6 ng/ml. The values were 0.0-287.4 ng/ml for dogs with pancreatitis, and those from dogs with gastrointestinal disease were 5.5-58.9 ng/ml. The only statistically significant difference (P<0.01) occurred between the TLI level of healthy dogs and those with EPI. The ICT kit showed high reproducibility, and the TLI values yielding negative results differed significantly (P<0.01) from those returning positive results. The ICT kit yielded negative results (indicating EPI) from clinical serum samples with TLI concentrations of 0.0-4.1 ng/ml by ELISA. Both the ELISA and ICT kit are useful tools in the diagnosis of canine EPI.     

Susceptibility of liver proliferative lesions in heterozygous p53 deficient CBA mice to various carcinogens

To investigate the liver tumorigenic sensitivity to various carcinogens in heterozygous p53 deficient [p53 (+/-)] CBA mice and their wild-type littermates [p53 (+/+) mice], 71 p53 (+/-) and 74 p53 (+/+) CBA mice (male, 6-12 weeks of age) were given diet containing 4,000 or 0 ppm flumequine (FL) for 26 weeks or a single intraperitoneal injection of 5 mg/kg body weights dimethylnitrosamine (DMN) at start of the study in Exp. 1, diet containing 6,000 or 0 ppm di(2-ethylhexyl)-phthalate (DEHP) for 26 weeks in Exp. 2, or diet containing 12,000, 6,000 or 0 ppm phenolphthalein (PhP) for 26 weeks in Exp. 3. All surviving animals of these groups were killed after completion of treatment of the test substances for 26 weeks. In the FL groups, the incidences of hepatocellular altered foci in p53 (+/-) mice, the multiplicities of those in p53 (+/-) and p53 (+/+) mice were significantly increased as compared to the corresponding control groups. The incidences and multiplicities of altered foci in the DMN groups were higher than those in the corresponding control groups in p53 (+/-) and p53 (+/+) mice, but no significant differences were indicated between the groups. There were no significant differences in the incidences, multiplicities and proliferating cell nuclear antigen labeling indices of altered foci in the FL or DMN groups between p53 (+/-) and p53 (+/+) mice. There were no significant differences in the incidences and multiplicities of altered foci between the DEHP or PhP and control groups. The present results suggest that p53 gene knocked out heterozygously does not enhance the chemical hepatocarcinogenesis in CBA mice.