An abattoir survey of diseases of feral goats

Three cases of paresis due to vertebral abscess in Shiba goats in Japan

Three Shiba goats aged 1 to 7 years kept in Ibaraki prefecture in Japan were presented with chief complaint of lumbar paralysis or gait abnormalities. As cerebrospinal setariasis were suspected in all cases at the first stage, ivermectin was administered to treat, but the response was insufficient. Necropsy revealed abscess formation on the ventral side of the spine at T5 in Case 1, T5-6 in Case 2, and C7-T1 in Case 3, causing compression of the spinal cord in all three cases. In addition to cerebrospinal setariasis, vertebral abscess should be considered as a cause of paresis or gait abnormalities in goats in Japan. Computed tomography was a useful for diagnosing vertebral abscess.

A review of coxiellosis (Q fever) and brucellosis in goats and humans: Implications for disease control in smallholder farming systems in Southeast Asia

Coxiella burnetii and Brucella spp. are pathogenic bacteria that can cause large-scale outbreaks in livestock. Furthermore, these infectious agents are capable of causing zoonotic infections and therefore pose a risk to the close relationship between farm households and their livestock, especially goats. A review of seroprevalence studies of Coxiella burnetii and Brucella spp. in domestic goats demonstrated large differences in the total number of samples tested in different regions and countries. This review aims to provide information on coxiellosis (Q fever in humans) and brucellosis in goats concerning the characteristics of the causative agent, surveillance, and available prevention and control measures at a global level. Implications for Coxiella burnetii and Brucella spp. infections in domesticated goats in Southeast Asia are discussed.

Are feral goats intermediate hosts for Linguatula (Pentastomida) in Australia?

Feral goats, Capra hircus (Bovidae), currently occur across 28% of Australia, and are found in all states and territories as well as some offshore islands. Feral goats are harvested for live export or processed as game meat, with feral goats making up approximately 90% of goats sent to slaughter in Australia. Nymphs of the pentastomid parasite, Linguatula serrata, are common parasites of goats elsewhere in the world, where they cause Halzoun or Marrara disease in humans through the consumption of nymphs in raw or semi-cooked edible offal. Despite being commonly encountered in cattle at slaughter in Australia, L. serrata nymphs have never been reported from feral goats in Australia. Goats at slaughter, however, commonly show infections of lymph nodes, the majority of which are diagnosed as caseous lymphadenitis caused by bacteria, although a small number have no known aetiology. Examination of 33 feral goats from locations in New South Wales and South Australia found a Linguatula sp. nymph encased in the mesenteric lymph node of one goat from the Cooma region of New South Wales. The potential risk of transmission of Linguatula sp. to humans and other domestic animals is discussed. This study has highlighted the importance of continued surveys of feral animals for infection with parasites, especially as their distribution changes.

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An infective nymphal Linguatula sp. was collected from the lymph nodes of a feral goat in Australia.

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This is the first report of the feral goat as an intermediate host for Linguatula in Australia.

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Linguatula poses a zoonotic risk.

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The importance of continued surveys of parasites of feral animals is highlighted.

New insights on the epidemiology of Coxiella burnetii in pet dogs and cats from New South Wales, Australia

Q fever is considered one of the most important zoonoses in Australia. Whilst ruminants are the primary reservoirs for Coxiella burnetii, and the major source of human infection, human cases have also been reported following contact with pet dogs and cats. This study aimed to estimate the prevalence of seropositivity to, and bacterial shedding of, C. burnetii by pet dogs and cats in a region with a high human Q fever incidence and explore risk factors for C. burnetii exposure. Samples (serum, whole blood, reproductive tissue, reproductive swabs) and questionnaires (completed by the pet's owner) were collected from dogs and cats from eight communities across remote New South Wales (NSW), Australia. Overall 86/330 dogs (26.1%, 95% CI 21.3-30.8%) and 19/145 cats (13.1%, 95% CI 7.6-18.6%) were seropositive to C. burnetii. Seroprevalence varied significantly between communities and was highest in communities within 150 km of a 2015 human Q fever outbreak. Feeding raw kangaroo was identified as a risk factor for seropositivity (adjusted OR 3.37, 95% CI 1.21-9.43). Coxiella burnetii DNA was not detected from any dog or cat whole blood, reproductive tissue or vaginal/preputial swab using qPCR targeting the IS1111 and com1 genes. Our findings suggest that companion animals are frequently exposed to C. burnetii in western NSW. Geographical variation in C. burnetii seroprevalence amongst companion animals - which corresponds with a human Q fever outbreak - suggests a shared environmental source of infection is likely with important consequences for public and animal health. The lack of detection of C. burnetii DNA from healthy companion animals suggests that pet dogs and cats are not an important reservoir for human Q fever infection outside a narrow periparturient window.

Comparison of postmortem inspection procedures for detecting caseous lymphadenitis of Australian sheep and goats

Alternative postmortem inspection procedures for the detection of gross abnormalities due to Caseous Lymphadenitis (CLA) of sheep and goats were compared quantitatively against the current Australian Standard (AS4696). Studies on sheep and goats in Australia during 2016 addressed data gaps regarding current prevalence, combinations of multiple lesions within affected carcases and sensitivity of inspection procedures enabling a comparison of alternative with current procedures. Using these contemporary inspection data from 54 915 sheep and 48 577 goats a desktop study estimated the effect of implementing alternative procedures of reduced palpation from eleven carcase sites to the four sites most commonly affected. Under current procedures it was estimated that 86 sheep and 34 goat carcases with CLA lesions are missed per 10,000 carcases. Under alternative procedures it is estimated that an additional 48.4 sheep and 10.5 goat carcases with CLA lesions would be missed per 10 000 carcases. Of these, 38.2 sheep and 5.6 goat per 10 000 carcases would contain CLA only in routinely discarded, non-edible tissue sites. Hence, only an additional 10.2 sheep and 4.9 goat carcases per 10 000 inspected, with CLA in edible tissue sites are estimated to be missed. These alternative procedures have now been officially implemented in the Australian domestic standard.

Evaluation of the risk factors influencing the spread of caseous lymphadenitis in goat herds

Epidemiological studies on caseous lymphadenitis were carried out in Poland in 1996 and 2002 among goat herds covered by a milk recording program. Between-herd seroprevalence was 13.2% in 1996 and increased to 62.5% in 2002. The average size of seropositive herds was statistically significantly higher than that of seronegative ones, however there was no statistically significant difference in the age between the herds. A statistically significant prevalence ratio (PR) was identified and relevant attributable risk for exposed animals (AR(exp)) was calculated for the following risk factors: presence of seropositive males in a herd (PR = 8.350; AR(exp) = 0.651), presence of superficial abscesses in animals (PR = 6.142; AR(exp) = 0.620), presence of respiratory signs (PR = 2.900; AR(exp) = 0.393), presence of animals in poor condition in a herd (PR = 2.774; AR(exp) = 0.390) and occurrence of reproductive failures in a herd (PR = 1.798; AR(exp) = 0.230). Purchase of animals from abroad, mastitis and husbandry conditions (housing system, grazing system, hygienic conditions) were not shown to be statistically significant risk factors.

A qualitative assessment of Toxoplasma gondii risk in ready-to-eat smallgoods processing

Toxoplasma gondii is one of the most common parasitic infections of humans and other warm-blooded animals. In most adults, it does not cause serious illness, but severe disease may result from infection in fetuses and immunocompromised people. Consumption of raw or undercooked meats has consistently been identified as an important source of exposure to T. gondii. Several studies indicate the potential failure to inactivate T. gondii in the processes of cured meat products, This article presents a qualitative risk-based assessment of the processing of ready-to-eat smallgoods, which include cooked or uncooked fermented meat, pâté, dried meat, slow cured meat, luncheon meat, and cooked muscle meat including ham and roast beef. The raw meat ingredients are rated with respect to their likelihood of containing T. gondii cysts and an adjustment is made based on whether all the meat from a particular source is frozen. Next, the effectiveness of common processing steps to inactivate T. gondii cysts is assessed, including addition of spices, nitrates, nitrites and salt, use of fermentation, smoking and heat treatment, and the time and temperature during maturation. It is concluded that processing steps that may be effective in the inactivation of T. gondii cysts include freezing, heat treatment, and cooking, and the interaction between salt concentration, maturation time, and temperature. The assessment is illustrated using a Microsoft Excel-based software tool that was developed to facilitate the easy assessment of four hypothetical smallgoods products.

Corynebacterium pseudotuberculosis and its role in ovine caseous lymphadenitis

Caseous lymphadenitis (CLA) of sheep, caused by Corynebacterium pseudotuberculosis, has been a significant disease in the majority of sheep-rearing regions for over a century. Because of the chronic and often sub-clinical nature of the infection, it has proved difficult to control and prevalence is high in many parts of the world, which in turn leads to significant economic losses for farmers. This review describes the important characteristics of C. pseudotuberculosis and examines the pathogenesis and epidemiology of the infection in sheep. The review also discusses the immune response to infection and describes the methods that have been developed to control CLA, with particular emphasis on the use of vaccination and serological testing.

Corynebacterium pseudotuberculosis infection in goats. IX. The effect of vaccination against natural infection

A vaccination trial was carried out in 10 infected herds. The trial included 247 female kids, the number of animals in each herd varying from 15 to 38. About half of the animals in each herd were vaccinated twice at 3 to 4 week intervals, the first vaccination being carried out before the age of 4 months. A combination of a crude filtrate of C. pseudotuberculosis toxoid with whole organisms, was used. Overall, the prevalence of animals with superficial swellings was higher in the unvaccinated than in the vaccinated group during the first 1-2 years following immunization. However, in some herds superficial swellings were as common in vaccinated as in unvaccinated animals. An antibody response following vaccination was demonstrated in the hemolysis inhibition test, but not in the bacterial agglutination test. Superficial swellings were more common in vaccinated animals which were negative than in animals which were positive in the hemolysis inhibition test at 1 1/2 months after vaccination. The vaccine used in the present study, was not sufficiently efficacious to be recommended as the only protective measure against caseous lymphadenitis in Norwegian goat herds.

Prevalence and distribution of caseous lymphadenitis in feral goats

A total of 2,920 feral goats from pastoral areas of Western Australia were examined and the prevalence of caseous lymphadenitis was estimated to be 7.8 +/- 0.9% in goats presented for slaughter. Head, body and visceral lesions were present in 49.3%, 46.7% and 12.3% of affected goats, respectively. A comparison with previously reported data from sheep has been made and significant differences are discussed. Lung lesions were relatively uncommon in goats, whereas the distribution of carcase lesions was similar between the species. Multiple lesions appear to be less common in goats than in sheep.

The prevalence and pathogenicity of Chorioptes bovis (Hering, 1845) and Psoroptes cuniculi (Delafond, 1859) (Acari: Psoroptidae) infestations in feral goats in New Zealand

Between October 1976 and January 1980 a total of 368 feral goats was examined in New Zealand for the presence of Chorioptes bovis and 434 for the presence of Psoroptes cuniculi. The seasonal pattern of C. bovis infestation in feral goats was similar to that seen in sheep and cattle. The prevalence of infestation reached 100% in July and August (winter) and declined to 27% in February and March (summer). Fewer goats were infested with P. cuniculi and prevalence of infestation reached a maximum of 41% in July. No goats were found infested in the December and January samples. Chorioptes bovis infestation was independent of the age and sex of hosts. Infestation with P. cuniculi was independent of the sex of the hosts, but older goats were more frequently infested (16%) than younger goats (8.6%). Unilateral infestation with P. cuniculi was more common (74.5%) than bilateral infestation. No severe lesions were associated with C. bovis, but 21.3% of goats with P. cuniculi had the external auditory meatus blocked by waxy material and 12.8% had scabby encrustations on the ears. The importance of goats as a possible source of infestation to domestic animals is discussed.