The epizootiology of ephemeral fever in Australia from its first recognition until 1968 was reviewed. Since 1968, ephemeral fever often in a silent form has been shown to be enzootic in northern Australia, by the use of sentinel cattle. The major epizootics which occured in 1970-1971, 1972-1974 and 1974-1975 are described. These epizootics were characterised by an apparently rapid movement of disease in a general north-south direction in summer months. Ephemeral fever antibody was detected in 11% of 1009 domesticated and feral water buffaloes.
A total of 386 clinical outbreaks of anaplasmosis were confirmed In Queensland south of the 22nd parallel over the period 1967 to 1976. Seventy-eight per cent of these outbreaks occurred during autumn and winter and only 6.8% involved cattie less than 1 year of age compared with 54.8% for cattle more than 3 years old. Dairy breeds were involved in 48.1% of 258 outbreaks compared with 51.9% for beef breeds. 60s faurus beef breeds were involved in 90.7% of 118 outbreaks compared with 9.3% for Bos indicus crossbreds. Approximately 3 J F Y A M J J A s o N D fected. Month Male cattle were involved in 21.8% of 244 outbreeds were involved in 48.1070 of 258 outbreaks Figure 2 The number of confirmed clinical outbreaks of Anaplasmosts per breaks 'Ompared with 78*2'0 for Dairy month in southern Queensland from 1967 lo 1976 inclusive.
SUMMARY A severe cattle mortality in which 132 out of 340 animals died on a property in southern Queensland was investigated. Clinical signs shown by affected animals included fever, inappetance, depression, lethargy, salivation, diarrhoea, ataxia, and ulceration of the oral cavity. The most common lesions seen at autopsy of 6 affected animals were ulceration of the tongue, gums, dental pad and buccal mucosa, linear ulceration of the caudal third of the oesophagus, mild catarrhal enteritis and necrosis of lymph nodes draining areas of ulceration. Bovine herpesvirus type 1 (BHV 1) was isolated from 3 out of 5 animals from which virus isolation was attempted. BHV 1 was recovered from oesophageal ulcers, retropharyngeal lymph nodes, blood clot, and swabs from ulcers in the oral cavity but not from spleen, liver or mesenteric lymph node. Serum neutralising (SN) antibody to BHV 1 was detected in 4 out of 12 affected animals in the second of paired serum samples but not in the first. Mucosal Disease (MD) virus was not recovered from any of 17 animals from which isolation was attempted but moderate MD SN titres, without a rise on paired sera, were detected in affected animals. Fever, depression, inappetance, ulceration of the upper alimentary tract, and adrenal necrosis were produced in 2 susceptible animals following inoculation with third passage cell culture fluid containing BHV 1. A serological response to BHV 1, but not to MD virus was detected in one of the cattle infected experimentally.
This paper reports those findings concerning property management from the 1977-78 survey of tick control in Queensland, which could effect efficient tick control and also presents a profile of the cattle industry in the tick infested areas at the time of the survey. The average property size was 400 hectares and the average number of cattle on the properties was 726.4. Larger properties tended to have crossbred Zebu cattle. The average number of paddocks per property was 7.2. The most popular stabilised crossbred Zebu breed was Santa Gertrudis but the most common type of cattle was crossbred Zebu, which was on 30% of properties. There were negligible numbers of crossbreed Zebu cattle on dairy properties. Control of other external parasites may result in additional dippings in areas where they occur. Although fence maintenance appears to be carried out regularly it is clear that the effectivness of tick control measures, such as pasture spelling and dipping which depend on clean musters, could be affected by the occurrence of fire, floods and other natural disasters on half the properties in the tick infested areas. There is no evidence from results in the survey that attention to other farming activities (mainly cropping) prevents producers from paying sufficient attention to tick control. In fact cropping often provides the opportunity for producers to rotate cattle around pastures. Producers appear to consider the cost of tick control is a burden and they expect assistance from the Government to reduce these costs. They do not appear to have considered how they can reduce the costs themselves.
Serums from unvaccinated groups in 5 herds of beef-cattle in South-East Queensland were tested for antibodies to Babesia argentina at intervals while the cattle were increasing in age from about 6 months. An indirect fluorescent antibody test was used. Infection rates, indicating the proportions of the groups that had been exposed to tick-transmitted infection were 49.2, 56.9 and 69.1% for cattle aged approximately 6, 12 and 18 months, respectively. The degree to which cattle were infested with the vector, Boophilus microplus, was estimated. There appeared to be a strong correlation between infection rate and tick incidence. Four serologically negative animals died of either confirmed or suspected babesiosis during the sampling period. Sickness was observed in 5 others. The serological status of 57 changes from negative to positive without symptoms being observed, indicating relatively low mortality and morbidity rates in the enzootic situation studied.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.