Epidemiology of abomasal nematodes of dairy cattle in Hokkaido, northern Japan

The prevalence and intensity of infection with abomasal nematodiasis was studied in dairy cattle of Hokkaido, northern Japan, for successive two years. During the period of March in 1985 to September in 1987, a total number of 393 abomasa of Holstein-Friesian cows was examined for nematode parasites. Nematodes were detected from 75% of the cows. The prevalence of nematode species detected was Ostertagia ostertagi 250 (63.6%), Mecistocirrus digitatus 181 (46.1%), Trichostrongylus axei 85 (21.6%) and Haemonchus sp. 1 (0.3%). The prevalence and population composition of each growth stage varied seasonally in O. ostertagi and M. digitatus. The large percentage of arrested larvae, early L4 O. ostertagi and immature L5 M. digitatus, detected during the mid-winter and the increasing percentage of matured adult populations of both species in early spring revealed the occurrence of the autumn associated arrested development (hypobiosis) phenomenon in bovine abomasum nematodes of Japan.     

Efficacy of febantel against abomasal nematodes and lungworms in cattle

The efficacy of febantel at a dosage of 5 mg/kg (45.5% paste formulation) against inhibited early 4th-stage larvae (EL4) of Ostertagia ostertagi, other nematodes of the abomasum, and Dictyocaulus viviparus was investigated in 4- to 6-month-old Holstein calves that grazed on pasture heavily contaminated with parasites from February 24 to April 1, 1986 (36 days). In Louisiana, this is the first month of a 3-month period in which increasing numbers of inhibition-prone O ostertagi larvae are acquired, and infection risk with D viviparus may remain high. Three of 4 calves that died of lungworm infection during the pasture-exposure period were necropsied. Large numbers of abomasal nematodes, including inhibited O ostertagi larvae, and large numbers of D viviparus were recovered. Twenty-five calves were randomly allotted by equal distribution of body weight to 2 groups and treated on April 4: placebo-treated calves (n = 13) and febantel-treated calves (n = 12). Equal numbers of treated and control calves were killed at 6 and 7 days, respectively, after treatment. Mean numbers of O ostertagi in control cattle were: adults, 4,931; developing 4th-stage larvae (DL4), 1,119; and inhibited EL4, 3,410. Ostertagia lyrata, Trichostrongylus axei, Haemonchus sp, and D viviparus were well distributed in nearly all control calves. Percentage reduction of O ostertagi in treated calves, when compared with controls, was: adults, 83.6%; DL4, 57.8%; and inhibited EL4, 34.8%. Percentage reductions of other species were: O lyrata, 92.6%; T axei adults, 99.3% and 4th-stage larvae (L4), 100%; Haemonchus sp adults, 66.7%, and L4, 64%; D viviparus adults 90.6%, and immature forms, 97.1%.(ABSTRACT TRUNCATED AT 250 WORDS)     

Molecular detection of Mycoplasma wenyonii and 'Candidatus Mycoplasma haemobos' in cattle in Hokkaido, Japan

Blood samples from 78 cattle were tested for hemoplasma infection using molecular methods. PCR and sequence analysis revealed that 17 cattle were infected with Mycoplasma wenyonii, while 13 were infected with 'Candidatus Mycoplasma haemobos'. Four animals were infected with both species. This is the first study to report hemoplasma species infection among cattle in Japan.     

Epizootiological survey of Trichinella spp. infection in carnivores, rodents and insectivores in Hokkaido, Japan

In order to evaluate the present epidemiological situation of Trichinella infection in wild animals in Hokkaido, Japan, red foxes (Vulpes vulpes), raccoon dogs (Nyctereutes procyonoides) , brown bears (Ursus arctos) , martens (Martes melampus), rodents and insectivores captured in Hokkaido were examined for muscle larvae by the artificial digestion method from 2000 to 2006. Foxes (44/319, 13.8%), raccoon dogs (6/77, 7.8%) and brown bears (4/126, 3.2%) were found to be infected with Trichinella larvae and all other animal species evaluated were negative. Multiplex PCR and DNA sequencing revealed that larvae from a fox captured in Otofuke, in south-eastern Hokkaido, were T. nativa, and larvae from 27 animals including 21 foxes, 2 raccoon dogs and 4 brown bears captured in western Hokkaido were Trichinella T9.     

A survey of abomasal ulceration in veal calves

Abomasal ulceration was found in 264 of 304 commercially reared veal calves at slaughter. The incidence and severity of lesions were greatest in loose housed calves with access to straw and fed milk substitute ad libitum. The majority of lesions were located in the distal pylorus. There was no evidence that the abomasal erosions and ulcers found in the majority of veal calves affected their growth rate or were deleterious to their welfare. It is suggested that pyloric ulceration may be related to the diet of veal calves.     

Risk factors for abomasal volvulus and left abomasal displacement in cattle.

A hospital-based case-control study was conducted to evaluate and compare risk factors for abomasal volvulus (AV) and left displaced abomasum (LDA) in cattle. Medical record abstracts were derived from 17 North American veterinary schools by the Veterinary Medical Data Program for all cattle admitted between Jan 1, 1977 and Dec 31, 1986, and for those with a diagnosis of AV or LDA. From a total of 108,956 individual cattle records, 1,036 cases of AV and 7,695 cases of LDA were identified, with a ratio of LDA to AV cases of 7.4 to 1. In-hospital mortality was 23.5% for AV and 5.6% for LDA. Age, breed, gender, and season each had significant (P less than 0.05) effects on risk for AV and LDA. Risk for AV and LDA increased with increasing age, with greater risk in cattle aged 4 to 7 years. Dairy cattle were at higher risk of developing AV (adjusted odds ratio, 36.4) and LDA (adjusted odds ratio, 95.2) than were beef cattle. The odds of AV in Brown Swiss cattle were significantly (P less than 0.0001) lower, and the odds of LDA in Guernsey cattle were significantly (P less than 0.0001) higher than those in Holstein cattle. Female cattle were also at higher risk of developing AV (adjusted odds ratio, 3.3) and LDA (adjusted odds ratio, 29.1) than were male cattle. The odds of AV and LDA varied considerably throughout the year, with the lowest number of cases observed in autumn. Seasonal development of AV differed significantly (P less than 0.0001) from that of LDA, with the odds of AV and LDA being highest in January and March, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Interpretation of abomasal worm burdens in cattle

The significance of the worm burden in the diagnosis of parasitic gastroenteritis is examined. It is emphasised that the worm population is in a dynamic state with the calf constantly losing part of its worm burden while picking up new infective larvae. The numbers and proportion of late fourth stage Ostertagia ostertagi larvae gives an indication of the success of the animal in controlling its worm burden. During an examination of the worm population it is also necessary to look at the condition and degree of development of adult female worms to assess the efficiency of the calf's acquired resistance to infection.     

Genetic and antigenic characterization of bovine viral diarrhea viruses isolated from cattle in Hokkaido,Japan

In our previous study, we genetically analyzed bovine viral diarrhea viruses (BVDVs) isolated from 2000 to 2006 in Japan and reported that subgenotype 1b viruses were predominant. In the present study, 766 BVDVs isolated from 2006 to 2014 in Hokkaido, Japan, were genetically analyzed to understand recent epidemics. Phylogenetic analysis based on nucleotide sequences of the 5′-untranslated region of viral genome revealed that 766 isolates were classified as genotype 1 (BVDV-1; 544 isolates) and genotype 2 (BVDV-2; 222). BVDV-1 isolates were further divided into BVDV-1a (93), 1b (371) and 1c (80) subgenotypes, and all BVDV-2 isolates were grouped into BVDV-2a subgenotype (222). Further comparative analysis was performed with BVDV-1a, 1b and 2a viruses isolated from 2001 to 2014. Phylogenetic analysis based on nucleotide sequences of the viral glycoprotein E2 gene, a major target of neutralizing antibodies, revealed that BVDV-1a, 1b and 2a isolates were further classified into several clusters. Cross-neutralization tests showed that BVDV-1b isolates were antigenically different from BVDV-1a isolates, and almost BVDV-1a, 1b and 2a isolates were antigenically similar among each subgenotype and each E2 cluster. Taken together, BVDV-1b viruses are still predominant, and BVDV-2a viruses have increased recently in Hokkaido, Japan. Field isolates of BVDV-1a, 1b and 2a show genetic diversity on the E2 gene with antigenic conservation among each subgenotype during the last 14 years.     

Bleeding abomasal ulcers in adult dairy cattle

Case records of abomasal ulcers in adult dairy cattle admitted to the University of Pennsylvania during a 12-year period were reviewed. The only records retrieved were those for cases in which the clinical signs were directly associated with gastrointestinal bleeding. Of 6,385 adult cows admitted during the study period, 69 had clinical ulceration. Twenty-four were bleeding ulcers: 12 nontumor-associated bleeding ulcers and 12 lymphosarcoma-associated bleeding ulcers. Nontumor-associated bleeding ulcers were commonly found in young cows (7 cows less than or equal to 4 years old) that often had concurrent postparturient disease conditions. Lymphosarcoma-associated bleeding ulcers were found more commonly in older cows (10 cows greater than or equal to 6 years old) during all stages of lactation, often without concurrent diseases (8 cows).     

Absence of hypobiosis in abomasal nematodes of sheep and goats in Egypt

A total of 96 abomasa from sheep and goats at the Zagazig abattoir, Sharkia Province, Egypt, were examined, during the four climatic seasons from April 1986 to March 1987, for the presence of adult and larval nematodes. Adults of Trichostrongylus axei were most numerous followed by adult Haemonchus contortus. Adult Ostertagia sp. and Parabronema skrjabini were less prevalent. There was no significant difference between sheep and goats in infection rates, but worm burdens of the nematodes other than Ostertagia sp. were significantly higher (P less than 0.05) in sheep than in goats. The animals were uniformly infected with these parasites throughout the year as there were no significant differences in the incidence or intensity of infections between the four seasons. The numbers of larvae recovered from the wall of the abomasa were small in relation to the total adult worm population throughout the year with a slight increase during the summer. Hypobiosis, therefore, seems not to be important in the life cycle of abomasal nematodes of sheep and goats in Sharkia Province, Egypt.     

奶牛真胃积食的诊疗

1　发病情况病奶牛 4岁 ,体重约 60 0 kg。平时饲喂铡碎的地瓜秧及少量精料。第 1次出诊时 ,该奶牛已发病 7天。初步诊断为不完全肠套叠 ,需手术治疗。在拉往动物保健医院的途中 ,患牛排出一些粪便 ,畜主认为好转不想手术 ,带药回家采取保守治疗。发病第 1 1天 ,仍然无食欲 ,不     

Host specificity of abomasal nematodes in free ranging alpine ruminants

Abomasums from 641 alpine wild ruminants representing five different species (Cervus elaphus, Capreolus capreolus, Rupicapra rupicapra, Capra ibex, Ovis musimon) and from 19 domestic sheep (Ovis aries) from alpine areas were examined in order to investigate the host-specificity of abomasal helminths. Nine out of 20 helminth species were found in at least five different host species. A discriminant analysis was able to significantly discriminate the hosts on the basis of their helminth community composition with the exception of O. musimon and O. aries. Based on the correlation between each variable represented by helminth species with the most explanatory discriminant axis, it was possible to classify helminths into specialists and generalists. Specialists are represented by the dominant species in a community of an host species or family while generalists appear in the communities of many different hosts as intermediate species. Due to the pathogenic potential of some of these generalist species (i.e. Haemonchus contortus, Trichostrongylus axei) and their ability to adapt easily to the conditions found in several different hosts, they appear to be the most important from a sanitary point of view.     

Cryptosporidium infection of cattle in the Tokachi district,Hokkaido

The prevalence of Cryptosporidium infection was examined in 480 healthy cattle (0-39 months old) in the Tokachi district in Hokkaido during the period from June to September in 2000 and from June to July in 2001. C. parvum oocysts were detected in 6 of 50 cattle (0-2 months old) in 2001; while C. muris was detected in 2 of 56 cattle (6-8 months old) in 2001, in 1 of 15 cattle (9-11 months old) in 2001, in 1 of 88 cattle (15-17 months old) in 2000, in 4 of 89 cattle (18-21 months old) in 2000 and in 2 of 53 cattle (21-23 months old) in 2000.     

Filarioid nematodes in cattle,sheep and horses in Finland

Background

In autumn 2006, Finnish meat inspection data revealed lesions in tendons, muscles and ligaments of bovine hind legs leading to partial condemnation of carcasses. In gross pathological examination at Finnish Food Safety Authority Evira, Oulu (now Fish and Wildlife Health) Research Unit, Onchocerca sp. (Filarioidea; Onchocercidae) nematodes were detected in lesions. Due to this, a pilot study was made in order to find out what filarioid nematodes do occur in cattle, horses and sheep in Finland.

Methods

Ventral skin biopsies from 209 dairy cattle and 42 horses, as well as blood samples from 209 cattle, 146 horses and 193 sheep, were collected from different parts of Finland and examined for microfilariae. Visceral organs and other tissues from 33 cattle with parasitic lesions were studied histopathologically.

Results

Onchocerca sp. microfilariae (mf), 240 μm long, range 225–260 μm, 5.4 μm thick, were found in 37% of the skin biopsies of cattle. All blood samples from cattle, horses and sheep and skin biopsies from horses were negative for mf. Ventral skin microfilaria prevalence in cattle was higher in southern Finland than in the North (p = 0.001). Animal age and sampling time was not associated with mf prevalence. The infection was evenly distributed among young and older animals. Macroscopic lesions on tissues included greenish-grey discolouration and often oedema. In most of the lesions, small pale nodules were seen on the fasciae. Histopathologic examination of the samples revealed mild to intense infiltration with eosinophilic granulocytes and multifocal nodular lymphoplasmacytic aggregations were seen. In some samples, there were granulomatotic lesions with central necrotic tissue and cell detritus, surrounded by eosinophilic granulocytes, lympho-, plasma- and histiocytes and some multinucleated giant cells. Around living nematodes no or only weak inflammatory changes were observed.

Conclusion

Onchocerca sp. infection in cattle was found to be common in Finland, but the amount of pathological changes leading to condemnation of infected parts is low compared to the mf prevalence. Pronounced pathological changes are distinct but rare and mild changes are difficult to distinguish. No other filarioid nematodes were observed from the animals and it appears that horses and sheep may be free from filarioid nematodes in Finland.