Aortic valve insufficiency caused by a hypoplastic aortic valve in a calf.

A 1-month-old crossbred calf was referred for examination due to marked systolic heart murmurs and poor growth. The heart murmur was most audible on the right side of the cranial thorax. Cardiomegaly was evident on chest radiography, and echocardiography demonstrated aortic regurgitation and decreased fractional shortening. Cardiomegaly, aortic root dilation and cardiac displacement were confirmed by computed tomography. At necropsy, the heart was enlarged, and all three aortic valve leaflets were irregularly shaped. In calves with chronic aortic insufficiency, remodeling displacement of the heart and aorta causes changes in the location and timing of heart murmurs. Therefore, aortic insufficiency cannot be ruled out when a systolic heart murmur can be observed in the right chest wall.

Changes in serum concentration and activity of diamine oxidase during the first month of life in calves.

The serum concentration and activity of diamine oxidase (DAO) in calves with or without diarrhea during the first month of life were examined. The serum DAO concentration was highest on day 0 after birth, and gradually decreased. No differences in serum DAO concentrations were observed between calves with diarrhea and control calves. In contrast, serum DAO activity was lowest on day 0 after birth, and gradually increased. Serum DAO activity in calves with diarrhea was lower than that in the control calves from day 20 after birth. These findings suggest that serum DAO activity and concentration are not correlated, and serum DAO activity is useful for assessing damage to the small intestinal mucosa in calves.

Subtype analysis and prevalence of mixed subtype infection of Blastocystis in farmed pigs from Chiba Prefecture, Japan.

Blastocystis is an intestinal eukaryote found globally in humans and a wide range of animals. Blastocystis has been reported in domestic pigs, with subtype (ST) 5 being the most dominant, followed by ST1 and ST3. PCR-sequencing is commonly used for ST identification in pigs, but it often results in an underestimation of the prevalence of mixed infections. Here, we aimed to investigate the ST distribution and prevalence of mixed ST infections of Blastocystis in pigs from Chiba Prefecture in eastern Japan. A total of 82 fecal samples positive for Blastocystis were collected from two different farms, A and B. PCR was performed using ST-specific primers for ST1, ST2, ST3, and ST5. The prevalence of single ST5 infections was 37.8% (31/82), whereas that of mixed infections with ST5 and other STs was 57.3% (47/82) . A high percentage of single ST5 infections was observed in sows, piglets, and weaners from farm A (13/15, 86.7%), whereas mixed infections of ST5 and other STs (ST1 and ST3) were observed in 3- to 5-month-old grower pigs (15/18, 83.3%). Similarly, in farm B, most sows and piglets under 1 month of age showed a single ST5 infections (12/17, 70.6%), whereas weaner, grower, and finisher pigs showed mixed infections with ST5 and other STs, including ST1, ST2, and ST3 (27/28, 96.4%). In domestic pigs, diet and rearing environments change dramatically over the course of the animal's lifetime, which may have caused this difference in the prevalence of mixed ST infections among different age groups.

Cleaning procedures and cleanliness assessments of bucket milkers and suckling buckets on Japanese dairy farms.

Cleanliness of milking equipment is known to be important for the safety of dairy products and to prevent the spread of diseases among cows. We investigated the cleaning procedures of milking equipment and suckling equipment on Japanese dairy farms, and the cleanliness of bucket milkers, suckling buckets, milk receivers, and bulk tanks, using adenosine triphosphate (ATP) bioluminescence test. Bulk tanks (except one bulk tank) and milk receivers were washed by automated cleaning, but all bucket milkers and suckling buckets were washed by manual cleaning. Detergents were often not used to clean bucket milkers and suckling buckets. The log10 transformed relative luminescence units (LRLU) of equipment washed by manual cleaning was higher than equipment washed by automated cleaning. Clean surfaces (≤2.2 LRLU) were only observed on the bulk tank and the milk receiver. More than 50% of the LRLU of the mouthpiece, the rubber packing of claw, and the nipple of the suckling bucket were determined dirty. These results suggest that the cleanliness of the bucket milkers and the suckling buckets washed by manual cleaning was lower than that of the equipment washed by automated cleaning, and may be due to insufficient cleaning procedures.

Effect of high-concentrate corn grain diet-induced elevated ruminal lipopolysaccharide levels on dairy cow liver function.

A high-concentrate diet destroys gram-negative bacteria in the cattle rumen, leading to elevated ruminal lipopolysaccharide (LPS) levels. LPS causes liver inflammation through the hepatic portal vein but little is known about the effects of rumen-derived LPS on liver function and the reproductive organs. In this study, we determined the effect of increasing rumen fluid LPS levels on liver function and genital LPS levels. Cows were assigned to control (CON; n=5) and high-concentrate diet (HC; n=7) groups. We observed that the ruminal LPS and haptoglobin (Hp) levels were significantly higher and albumin levels were lower in the HC group than in the CON group. In the HC group, The Hp levels and aspartate transaminase (AST) activity were significantly higher and the total cholesterol levels were significantly lower after high-concentrate diet feeding than before feeding. No differences were observed in LPS levels in the peripheral veins, hepatic veins, hepatic portal vein, uterine perfusate, and follicular fluids between the groups. In all samples, the LPS level in the hepatic portal vein blood positively correlated with the AST activity and serum amyloid A level. In conclusion, our results indicate that high-concentrate diets do not have a direct effect on the reproductive organs upon a moderate ruminal LPS level increase. However, an increased ruminal LPS influx into the liver might affect negatively liver function.

Survey of bovine foamy virus infection among cattle in Japan and comparison with bovine leukemia virus infection.

The prevalence of bovine foamy virus (BFV) infections in cattle on farms in the Kanto region of Japan was determined using agar gel immunodiffusion (AGID) test and polymerase chain reaction (PCR). Six out of 20 farms contained BFV-positive cattle. Furthermore, 16.7% (91/545) of all cattle tested positive for BFV. This suggested that BFV-infected cattle are widely prevalent in Japan. Positive results for BFV infection were consistent between AGID and PCR tests. Additionally, we tested for bovine leukemia virus (BLV) infections at nine farms, primarily those containing BFV-infected cows. At each farm, the infection rate of BFV was lower than that of BLV. Further, cattle that were PCR-positive but antibody-negative, indicating immune tolerance to BFV, were not detected.

Transient elastography: a novel, non-invasive method for the evaluation of liver stiffness and controlled attenuation parameter in cows.

This study investigated the use of transient elastography (TE) as a tool for the non-invasive evaluation of liver stiffness and controlled attenuation parameter (CAP) in cows. A total of 85 cows were used for this study. After the liver was located and subcutaneous tissue thickness was checked by means of ultrasonography, liver stiffness and CAP were measured using TE. At least 10 measurements were taken per individual cow. In addition, intraclass correlation coefficients were calculated for intra-rater and two-rater inter-rater reliability of liver stiffness and CAP measurement, and were evaluated. Of the 85 cows, 61 (71.8%) were measurable owing to their significantly less body weight and subcutaneous tissue thickness compared with those of unmeasurable cows. Liver stiffness showed no significant differences among sexes, ages, or breeds. CAP showed no significant differences among sexes and breeds. Intra- and inter-rater reliabilities for liver stiffness and CAP were almost perfect. Both liver stiffness and CAP could be quantitatively evaluated with good reproducibility in cows using TE, and CAP increased with the growth of the cows. However, evaluation was not possible in obese cows or cows with high values for subcutaneous tissue thickness or body weight.

Isolation of bovine foamy virus in Japan.

Bovine foamy virus (BFV) is endemic in many countries, but has not been reported in Japan. A syncytium-forming virus was isolated from peripheral blood leukocytes of clinically healthy cattle on a farm in Kanagawa prefecture during a periodic epidemiological survey of viral diseases. The isolate was propagated in primary fetal bovine muscle cells and subsequently passaged in Madin-Darby bovine kidney cells. Since the isolate appeared to be distinct from the viruses with syncytium-forming ability previously isolated in Japan, we attempted to identify it using genomic analyses and electron microscopy. A phylogenetic analysis revealed that the isolate belongs to the bovine foamy virus cluster and is highly similar to a BFV strain isolated in China. A sero-epidemiological survey was performed using agar gel immunodiffusion test with the isolated virus as the antigen, and five of the 57 cattle tested were found to be seropositive.

Eversion and ligation of a diverticulum: report of an inspirational case and subsequent animal study.

Although most patients with colonic diverticula have no symptoms, perforation or bleeding can be troublesome. Recently, we treated an elderly patient with a diverticular perforation of the sigmoid colon who required a loop colostomy and later resection of the diseased colon. Between the operations, the colostomy resembled a sea slug with horns, which represented eversions of the diverticula. This interesting phenomenon suggests that diverticula may be everted as pseudopolyps and ligated endoscopically. Therefore, the procedure was tested on a Landrace pig, of which the large bowel wall was pulled with an endoscope at 9 different sites using forceps (n=6) or suction (n=3) and ligated. Four days later, reexamination revealed total necrosis at 8 sites and ulceration at 1. The animal was well. The bowel removed 2 weeks later showed mucosal fold convergences without perforations. Our procedure can be used for prophylactic or therapeutic treatment of patients with colonic diverticula.

Loss of milk yield due to Akabane disease in dairy cows.

Akabane disease is an infection with clinical signs of congenital malformation and abortion in ruminants. Abnormal parturitions caused by Akabane disease result in great economic loss. The purpose of this study is to estimate the reduction in the milk yield from abnormal parturition due to Akabane disease. The data were collected from 33 Holstein cows on 11 farms. The animals had abnormal parturitions during the period from September 1998 to March 1999, and were diagnosed as having Akabane disease. The mean and standard deviation of the rate of reduction in the milk yield of 33 cows after abnormal parturition caused by Akabane disease was -11.4 +/- 14.9%. The means and standard deviations of the rate of reduction of four cows calving abnormally at 220-239 days of gestation, nine cows calving abnormally at 240-270 days of gestation, and 20 cows calving abnormally at 271-300 days of gestation were -26.6 +/- 24.7%, -14.7 +/- 11.0%, and -6.9 +/- 12.3%, respectively. In this study, we demonstrated that the rate of reduction in the milk yield in cows affected by Akabane disease was -11.4 +/- 14.9%, but values as high as -26.6 +/- 24.7% were reached in the comparison with the milk yield obtained after normal parturition.

Yersinia enterocolitica serovar O:8 infection in breeding monkeys in Japan.

In the period from December 2002 to January 2003, 5 of 50 squirrel monkeys (Saimiri sciureus) housed at a Zoological Garden in the Kanto region of Japan died following a few days' history of diarrhea. After this outbreak had ended in the squirrel monkeys, 1 of 2 dark-handed gibbons (Hylobates agilis) died in April of 2003, showing similar clinical signs. We examined the organs of 3 of the dead squirrel monkeys and of the dark-handed gibbon, and Yersinia enterocolitica serovar O:8, which is the most pathogenic serovar of Y. enterocolitica, was isolated. In order to determine the source and the transmission route of infection, 98 fecal samples (45 from squirrel monkeys, 20 from other monkeys of 18 different species, and 33 from black rats captured around the monkey houses) and 7 water samples were collected in the Zoological Garden, and were examined for the prevalence of Y. enterocolitica serovar O:8. Serovar O:8 was isolated from 21 of 65 monkeys (32.3%) and 5 of 33 (15.2%) black rats (Rattus rattus). Furthermore, we examined the 30 isolates using molecular typing methods, pulsed field gel electrophoresis (PFGE), ribotyping using the RiboPrinter system, and restriction endonuclease analysis of virulence plasmid DNA (REAP), and compared the isolates in this outbreak with Japanese O:8 isolates previously identified. Genotyping showed that almost all the isolates were identical, and the genotype of the isolates was highly similar to that from wild rodents captured in Niigata Prefecture. This is the first report of fatal cases of Y. enterocolitica serovar O:8 infection in monkeys anywhere in the world.

Sensitive and specific detection of Yersinia pseudotuberculosis by loop-mediated isothermal amplification.

We developed a loop-mediated isothermal amplification method able to detect Yersinia pseudotuberculosis strains in 30 min by using six primers designed by targeting the inv gene. This method is more sensitive than PCR and might be a useful tool for detecting and identifying Y. pseudotuberculosis.

Automated ribotyping, a rapid typing method for analysis of Erysipelothrix spp. strains.

Automated ribotyping classified 70 Erysipelothrix species strains, previously classified into 14 RAPD patterns and into 63 PFGE patterns, into 27 ribogroups. Twenty-three strains of the 70 analyzed and classified into 13 ribogroups were previously classified into six ribotypes by the traditional ribotyping method. Moreover, automated ribotyping differentiated seven strains that were not differentiated by PFGE. Therefore, automated ribotyping was more sensitive than RAPD and traditional ribotyping, and it might be a useful method for a rapid screening in epidemiological study of strains of this genus, and more accurate results can be obtained when this method is used together with PFGE.