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Gallenti R, Hussein HE, Alzan HF, Suarez CE, Ueti M, Asurmendi S, Benitez D, Araujo FR, Rolls P, Sibeko-Matjila K, Schnittger L, Florin-Christensen M. Unraveling the Complexity of the Rhomboid Serine Protease 4 Family of Babesia bovis Using Bioinformatics and Experimental Studies. Pathogens 2022; 11:pathogens11030344. [PMID: 35335668 PMCID: PMC8956091 DOI: 10.3390/pathogens11030344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Revised: 03/05/2022] [Accepted: 03/06/2022] [Indexed: 11/17/2022] Open
Abstract
Babesia bovis, a tick-transmitted apicomplexan protozoon, infects cattle in tropical and subtropical regions around the world. In the apicomplexans Toxoplasma gondii and Plasmodium falciparum, rhomboid serine protease 4 (ROM4) fulfills an essential role in host cell invasion. We thus investigated B. bovis ROM4 coding genes; their genomic organization; their expression in in vitro cultured asexual (AS) and sexual stages (SS); and strain polymorphisms. B. bovis contains five rom4 paralogous genes in chromosome 2, which we have named rom4.1, 4.2, 4.3, 4.4 and 4.5. There are moderate degrees of sequence identity between them, except for rom4.3 and 4.4, which are almost identical. RT-qPCR analysis showed that rom4.1 and rom4.3/4.4, respectively, display 18-fold and 218-fold significantly higher (p < 0.01) levels of transcription in SS than in AS, suggesting a role in gametogenesis-related processes. In contrast, transcription of rom4.4 and 4.5 differed non-significantly between the stages. ROM4 polymorphisms among geographic isolates were essentially restricted to the number of tandem repeats of a 29-amino acid sequence in ROM4.5. This sequence repeat is highly conserved and predicted as antigenic. B. bovis ROMs likely participate in relevant host−pathogen interactions and are possibly useful targets for the development of new control strategies against this pathogen.
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Affiliation(s)
- Romina Gallenti
- Instituto de Patobiología Veterinaria (IPVET), Centro de Investigaciones en Ciencias Veterinarias y Agronómicas, Instituto Nacional de Tecnología Agropecuaria—Consejo Nacional de Investigaciones Científicas y Técnicas (INTA-CONICET), Hurlingham 1686, Argentina; (R.G.); (L.S.)
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires C1033AAJ, Argentina
| | - Hala E. Hussein
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA; (H.E.H.); (H.F.A.); (C.E.S.); (M.U.)
- Department of Entomology, Faculty of Science, Cairo University, Giza 12613, Egypt
| | - Heba F. Alzan
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA; (H.E.H.); (H.F.A.); (C.E.S.); (M.U.)
- Tick and Tick-Borne Disease Research Unit, National Research Center, Giza 12622, Egypt
| | - Carlos E. Suarez
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA; (H.E.H.); (H.F.A.); (C.E.S.); (M.U.)
- US Department of Agriculture, Animal Disease Research Unit, (USDA-ARS), Pullman, WA 99163, USA
| | - Massaro Ueti
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA; (H.E.H.); (H.F.A.); (C.E.S.); (M.U.)
- US Department of Agriculture, Animal Disease Research Unit, (USDA-ARS), Pullman, WA 99163, USA
| | - Sebastián Asurmendi
- Instituto de Agrobiotecnología y Biología Molecular (IABiMo), Instituto Nacional de Tecnología Agropecuaria—Consejo Nacional de Investigaciones Científicas y Técnicas (INTA-CONICET), Hurlingham 1686, Argentina;
| | - Daniel Benitez
- Estación Experimental Agropecuaria (EEA)-Mercedes, Instituto Nacional de Tecnología Agropecuaria (INTA), Mercedes 3470, Argentina;
| | | | - Peter Rolls
- Department of Agriculture & Fisheries, Tick Fever Centre, Wacol, QLD 4076, Australia;
| | - Kgomotso Sibeko-Matjila
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort 0110, South Africa;
| | - Leonhard Schnittger
- Instituto de Patobiología Veterinaria (IPVET), Centro de Investigaciones en Ciencias Veterinarias y Agronómicas, Instituto Nacional de Tecnología Agropecuaria—Consejo Nacional de Investigaciones Científicas y Técnicas (INTA-CONICET), Hurlingham 1686, Argentina; (R.G.); (L.S.)
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires C1033AAJ, Argentina
| | - Mónica Florin-Christensen
- Instituto de Patobiología Veterinaria (IPVET), Centro de Investigaciones en Ciencias Veterinarias y Agronómicas, Instituto Nacional de Tecnología Agropecuaria—Consejo Nacional de Investigaciones Científicas y Técnicas (INTA-CONICET), Hurlingham 1686, Argentina; (R.G.); (L.S.)
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires C1033AAJ, Argentina
- Correspondence:
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Biesheuvel MM, Santman-Berends IMGA, Barkema HW, Ritter C, Berezowski J, Guelbenzu M, Kaler J. Understanding Farmers' Behavior and Their Decision-Making Process in the Context of Cattle Diseases: A Review of Theories and Approaches. Front Vet Sci 2021; 8:687699. [PMID: 34926632 PMCID: PMC8674677 DOI: 10.3389/fvets.2021.687699] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 10/21/2021] [Indexed: 11/13/2022] Open
Abstract
Understanding farmers' behavior regarding disease control is essential to successfully implement behavior change interventions that improve uptake of best practices. A literature review was conducted to identify theoretical underpinnings, analytical methodologies, and key behavioral determinants that have been described to understand farmers' behavior in disease control and prevention on cattle farms. Overall, 166 peer-reviewed manuscripts from studies conducted in 27 countries were identified. In the past decade, there were increasing reports on farmers' motivators and barriers, but no indication of application of appropriate social science methods. Furthermore, the majority (58%) of reviewed studies lacked a theoretical framework in their study design. However, when a theoretical underpinning was applied, the Theory of Planned Behavior was most commonly used (14% of total). The complexity of factors impacting farmers' behavior was illustrated when mapping all described key constructs of the reviewed papers in behavior change frameworks, such as the socioecological framework and the Capability, Opportunity and Motivation Behavior (COM-B) model. Constructs related to personal influences and relationships between farmers and veterinarians were overrepresented, whereas constructs related to other interpersonal and contextual environments were not extensively studied. There was a general lack of use of validated scales to measure constructs and empirically validated theoretical frameworks to understand and predict farmers' behavior. Furthermore, studies mainly focused on measurements of intention of stakeholder behavior rather than actual behavior, although the former is a poor predictor of the latter. Finally, there is still a lack of robust evidence of behavior change interventions or techniques that result in a successful change in farmers' behavior. We concluded that for a sustainable behavior change, studies should include wider constructs at individual, interpersonal, and contextual levels. Furthermore, the use of empirically validated constructs and theoretical frameworks is encouraged. By using coherent frameworks, researchers could link constructs to design interventions, and thereby take the first step toward theory-driven, evidence-based interventions to influence farmers' behavior for disease control.
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Affiliation(s)
- Marit M Biesheuvel
- Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | | | - Herman W Barkema
- Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Caroline Ritter
- Department of Health Management, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE, Canada
| | | | - Maria Guelbenzu
- Veterinary Sciences Division, Agri Food and Biosciences Institute, Belfast, Ireland
| | - Jasmeet Kaler
- School of Veterinary Medicine and Science, University of Nottingham, Nottingham, United Kingdom
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Productivity and health effects of anaplasmosis and babesiosis on Bos indicus cattle and their crosses, and the effects of differing intensity of tick control in Australia. Vet Parasitol 2008; 155:1-9. [PMID: 18472219 DOI: 10.1016/j.vetpar.2008.03.022] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2008] [Revised: 03/20/2008] [Accepted: 03/31/2008] [Indexed: 11/24/2022]
Abstract
Tick fever is an important disease of cattle where Rhipicephalus (Boophilus) microplus acts as a vector for the three causal organisms Babesia bovis, Babesia bigemina and Anaplasma marginale. Bos indicus cattle and their crosses are more resistant to the clinical effects of infection with B. bovis and B. bigemina than are Bos taurus cattle. Resistance is not complete, however, and herds of B. indicus-cross cattle are still at risk of babesiosis in environments where exposure to B. bovis is light in most years but occasionally high. The susceptibility of B. indicus cattle and their crosses to infection with A. marginale is similar to that of B. taurus cattle. In herds of B. indicus cattle and their crosses the infection rate of Babesia spp. and A. marginale is lowered because fewer ticks are likely to attach per day due to reduced numbers of ticks in the field (long-term effect on population, arising from high host resistance) and because a smaller proportion of ticks that do develop to feed on infected cattle will in turn be infected (due to lower parasitaemia). As a consequence, herds of B. indicus cattle are less likely than herds of B. taurus cattle to have high levels of population immunity to babesiosis or anaplasmosis. The effects of acaricide application on the probability of clinical disease due to anaplasmosis and babesiosis are unpredictable and dependent on the prevalence of infection in ticks and in cattle at the time of application. Attempting to manipulate population immunity through the toleration of specific threshold numbers of ticks with the aim of controlling tick fever is not reliable and the justification for acaricide application should be for the control of ticks rather than for tick fever. Vaccination of B. indicus cattle and their crosses is advisable in all areas where ticks exist, although vaccination against B. bigemina is probably not essential in pure B. indicus animals.
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Shaw SA, Sutherland IA. The prevalence of Stephanofilaria sp. in buffalo fly, Haematobia irritans exigua, in Central Queensland. ACTA ACUST UNITED AC 2006. [DOI: 10.1111/j.1440-6055.2006.00545.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Sserugga JN, Jonsson NN, Bock RE, More SJ. Serological evidence of exposure to tick fever organisms in young cattle on Queensland dairy farms. Aust Vet J 2003; 81:147-52. [PMID: 15080428 DOI: 10.1111/j.1751-0813.2003.tb11077.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVES To compare the features of farms on which the exposure of young cattle to tick fever organisms is sufficient to ensure that immunity is high and the risk of clinical disease is low (endemic stability) with those of farms on which exposure is insufficient to induce widespread immunity (hence without endemic stability); to examine the relationships between the management of ticks and tick fever, and endemic stability to Babesia bovis, B. bigemina and Anaplasma marginale. DESIGN Cross-sectional study of 874 cattle between the ages of 6 and 15 months on 64 dairy farms, from three centres in south-eastern Queensland (Mutdapilly, Dayboro and Kenilworth) and one centre in far-north Queensland (Malanda). PROCEDURE Blood samples collected from between 5 and 20 calves from each farm were submitted for serological assay to determine exposure to B. bovis, B. bigemina and A. marginale. A questionnaire about the farm characteristics and the management of ticks and tick fever was completed with each farmer. RESULTS On 73% of farms, confirmed clinical cases of tick fever were recalled by the farmer, indicating that tick fever was a threat on most farms. The majority of herds in the study (54 of 64) did not have sufficient numbers of seropositive animals aged between 6 and 15 months to have a low risk of tick fever. Region had an effect on the likelihood of endemic stability for all tick fever organisms. Cattle near Malanda in Far-north Queensland were more likely to be seropositive to B. bovis and B. bigemina. The method, strategy and intensity of tick control were not related to the likelihood of endemic stability when the effect of region was considered. The decision to leave a few ticks on cattle in an effort to induce endemic stability did increase the likelihood of endemic stability to A. marginale. However, in practical terms, it was ineffective, because only 26% of these farms had endemic stability against all three organisms. CONCLUSIONS Given the low proportion of farms that have endemic stability to the tick fever organisms and the high likelihood of clinical disease, vaccination is recommended to protect dairy cattle from tick fever throughout the tick infested area of Queensland. However, further work is required to determine the economic value of vaccination, taking into account the costs of vaccination, of outbreaks and the protective value of vaccination.
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Affiliation(s)
- J N Sserugga
- School of Veterinary Science, The University of Queensland, PO Box 125, Kenmore, Queensland 4069
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Yamane I, Koiwai M, Tsusui T, Hamaoka T. A survey of Theileria sergenti infection, daily weight gain and conception proportions in 85 herds of grazing heifers in Japan. Vet Parasitol 2001; 99:189-98. [PMID: 11502366 DOI: 10.1016/s0304-4017(01)00458-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
A survey of Theileria sergenti infections, daily weight gain and conception proportion was conducted in 85 herds of grazing heifers in Japan. Basic information and epidemiological data from participating herds were obtained by mailed questionnaires, which were completed by field veterinarians. The average cumulative incidence and proportion of treated animals in the participating herds were 25.7 and 21.1%, respectively. The average daily weight gain and conception proportion were 0.51 kg per day and 56.9%, respectively. The basic information and epidemiological data had a large range and standard deviation, which reflect the wide diversity of the grazing herds in Japan. Herds with heavy tick infestation had significantly higher cumulative incidence and proportion of treated animals, therefore, this factor can be a good estimator to predict the occurrence and loss by theileriosis of the herds. The present questionnaire survey was useful for obtaining information about herds in different regions, and this survey method can be applied to the research of other animal diseases in Japan.
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Affiliation(s)
- I Yamane
- Laboratory of Epidemiology, National Institute of Animal Health, 3-1-1, Kannondai, Tsukuba-shi, Ibaraki 305-0856, Japan.
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Abstract
The term 'global change' is used to encompass all of the significant drivers of environmental change as experienced by hosts, parasites and parasite managers. The term includes changes in climate and climate variability, atmospheric composition, land use and land cover including deforestation and urbanisation, bio-geochemistry, globalisation of trade and transport, the spread of alien species, human health and technology. A subset of land use issues relates to the management of protective technologies in relation to residues in food and the environment and the emergence of resistance. Another is the question of changing biodiversity of both parasites and their associated natural enemies, and the effects on the host--parasite relationship and on parasite management. A framework for studying impacts of global change is proposed and illustrated with field data, and CLIMEX and simulation modelling of the cattle tick Boophilus microplus in Australia. Parasitology suffers from the perception that the key impacts of global change will be driven by changes at lower trophic levels, with parasitic interactions being treated as secondary effects. This is incorrect because the environment mediates host-parasite interactions as much as it affects parasites directly. Parasitologists need to strive for holistic solutions to the management of animal and human health, within a wider context of overall management of those systems, if they are to make a meaningful contribution to global efforts aimed at coping with global change.
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Affiliation(s)
- R W Sutherst
- CSIRO Entomology, Long Pocket Laboratories, 120 Meiers Road, Indooroopilly, Queensland 4068, Australia.
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Bock RE, Kingston TG, De Vos AJ. Effect of breed of cattle on innate resistance to infection with Anaplasma marginale transmitted by Boophilus microplus. Aust Vet J 1999; 77:748-51. [PMID: 10685172 DOI: 10.1111/j.1751-0813.1999.tb12920.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To assess the innate resistance of and transmission in naive Bos taurus cross Bos indicus and purebred Bos indicus cattle when placed in a paddock with cattle infected with Anaplasma marginale and carrying Boophilus microplus ticks. DESIGN A group of 49 purebred B indicus, and 48 B indicus cross B taurus (50%, F1 generation) 24-month-old steers were kept in the same paddock with cattle artificially infected with a virulent isolate of A marginale and Boophilus microplus. The cattle were seronegative for A marginale at the start of the trial but had previously been exposed to Babesia bovis and B bigemina. PROCEDURE Cattle were inspected twice weekly for 118 days. Whole blood, blood smears and serum samples were collected from the cattle on day 37 after exposure and then at regular intervals to day 83 after exposure to measure packed-cell volumes, parasitaemias and antibody titres to A marginale. Any animals that met preset criteria were treated for anaplasmosis. On day 83 all cattle were treated with an acaricide and cattle infected with A marginale were removed from the rest of the group. RESULTS A marginale was detected in blood smears from 14 crossbred and 9 B indicus steers between days 56 and 72 after exposure. Five and two of the infected crossbred and B indicus steers required treatment, respectively. One of the Bos indicus cattle died as a result of the A marginale infection despite treatment. Antibodies to A marginale were detected in the 23 infected cattle. The mean packed-cell volume depression was 40 and 37% in the affected crossbred and Bos indicus groups, respectively. There was no significant difference detected in susceptibility between these two groups. CONCLUSIONS Innate resistance of purebred B indicus and crossbred cattle was not significantly different. The results confirm that purebred B indicus and crossbred cattle are sufficiently susceptible to warrant the use of vaccination against Anaplasma infections.
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Affiliation(s)
- R E Bock
- Tick Fever Research Centre, Wacol, Queensland.
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Jonsson NN, Mayer DG. Estimation of the effects of buffalo fly (Haematobia irritans exigua) on the milk production of dairy cattle based on a meta-analysis of literature data. MEDICAL AND VETERINARY ENTOMOLOGY 1999; 13:372-376. [PMID: 10608225 DOI: 10.1046/j.1365-2915.1999.00179.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Published reports on the effect of buffalo fly Haematobia irritans exigua De Meijere (Diptera: Muscidae) and the closely related horn fly (H. irritans) were examined and analysed using non-linear weighted regression techniques in an attempt to establish the relationship between daily production loss (D), average number of parasites (n) and the average damage per parasite per day (d), and to provide estimates of expected losses in milk yield (MYD) and live-weight gain (LWG) in dairy cattle. A Mitscherlich three-parameter model was used to explain the relationship between the total loss of production attributable to buffalo flies and the average number of flies associated with cattle. This model was significant (P<0.01), with R2 = 20.2% and predicted a threshold number of flies (n = 30) below which no adverse effects would be noted. At a moderate level of infestation (n = 200) dMYD was 2.6 ml/fly/day and dLWG was 0.14 g/fly/day, resulting in estimated daily losses in milk yield (D(MYD)) and live-weight gain (D(LWG)) of 520 ml and 28 g, respectively.
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Affiliation(s)
- N N Jonsson
- Australian Tropical Dairy Institute, Queensland.
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Bock RE, Kingston TG, de Vos AJ. Effect of breed of cattle on transmission rate and innate resistance to infection with Babesia bovis and B bigemina transmitted by Boophilus microplus. Aust Vet J 1999; 77:461-4. [PMID: 10451733 DOI: 10.1111/j.1751-0813.1999.tb12093.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To assess the effect of breed of cattle on the transmission rates of and innate resistance to Babesia bovis and B bigemina parasites transmitted by Boophilus microplus ticks. DESIGN Groups of 56 purebred B indicus and 52 B indicus cross B taurus (50%, F1 generation) steers were placed in a paddock seeded with and also naturally infested with B microplus which were the progeny of females ticks fed on B taurus cattle specifically infected with a virulent isolate of B bovis. The cattle were placed in the infested paddock 50 days after seeding had started. PROCEDURE Cattle were inspected from horseback daily for 50 days. Clinically ill cattle were brought to yards and assessed by monitoring fever, depression of packed-cell volume, parasitaemia and severity of clinical signs. Any animals that met preset criteria were treated for babesiosis. Blood samples were collected from all cattle on day 28, 35 and 42 after exposure and antibodies to Babesia spp and packed cell volume measured. RESULTS All steers, except for one crossbred, seroconverted to B bovis and B bigemina by day 35 and 75% of the crossbred steers showed a maximum depression in packed cell volume of more than 15% due to infection with Babesia spp compared with only 36% of the B indicus group. Ten of the 52 crossbreds and 1 of the 56 B indicus steers showed severe clinical signs. Two of the crossbreds required treatment of which one died 2 weeks after initial treatment. CONCLUSIONS Pure-bred B indicus cattle have a high degree of resistance to babesiosis, but crossbred cattle are sufficiently susceptible to warrant the use of preventive measures such as vaccination. Transmission rates of B bovis and B bigemina to B indicus and crossbred cattle previously unexposed to B microplus were the same.
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Affiliation(s)
- R E Bock
- Tick Fever Research Centre, Wacol, Queensland,
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Jonsson NN, Matschoss AL. Attitudes and practices of Queensland dairy farmers to the control of the cattle tick, Boophilus microplus. Aust Vet J 1998; 76:746-51. [PMID: 9862066 DOI: 10.1111/j.1751-0813.1998.tb12306.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To determine practices for the control of cattle ticks on dairy farms in Queensland, the attitudes of farmers to tick infestations and to identify opportunities for and barriers against the introduction of non-chemical methods of tick control. DESIGN A survey of 199 dairy farmers from tick-infested parts of Queensland was undertaken by 20 dairy advisers and stock inspectors from October 1996 to June 1997. The sample was a proportional, random selection of dairy farms from four regions. A personal interview was conducted with each farmer and answers to 134 questions were obtained. RESULTS AND CONCLUSIONS Most farmers were not concerned by cattle ticks on their own farms, although they believed that ticks are important to the dairy industry. They were most concerned about the development of chemical resistance by cattle ticks. Inadequate facilities and lack of motivation appeared to be the factors most limiting to improving the methods of control. Most farmers claimed to have only small numbers of ticks at worst. Although a control program recommended by the Queensland Dairyfarmers' Organisation was well regarded by farmers, few had adopted it. Many farmers saw no need to implement a strategic control program.
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Affiliation(s)
- N N Jonsson
- Department of Primary Industries, Australian Tropical Dairy Institute, Queensland
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Rothwell JT, Hacket KC, Friend M, Farnsworth WR, Lowe LB. Efficacy of zeta-cypermethrin as pour-on or spray formulations for the control of buffalo fly (Haematobia irritans exigua) in cattle. Aust Vet J 1998; 76:610-2. [PMID: 9791712 DOI: 10.1111/j.1751-0813.1998.tb10240.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To determine the efficacy of zeta-cypermethrin in controlling buffalo fly (Haematobia irritans exigua). DESIGN Five field trials in northern and central Queensland. PROCEDURE Zeta-cypermethrin pour-on at 2.5 mg/kg, spray at 62.5 ppm, deltamethrin pour-on and pour-on vehicle were applied to groups of 20 cattle. Buffalo fly counts were conducted three times before treatment and 3, 7, 14, 21, 28 and 35 days after treatment. RESULTS In central Queensland where synthetic pyrethroid resistance in buffalo fly populations was rare, 2.5 mg/kg of zeta-cypermethrin pour-on gave good control of buffalo fly for 4 weeks and was better than a deltamethrin product. A zeta-cypermethrin spray used at 62.5 ppm gave 14 days control. In far-north Queensland where resistance to synthetic pyrethroids and heavy rain was common, the maximum period of efficacy of zeta-cypermethrin pour-on was reduced to 2 weeks. CONCLUSION In areas where there is low resistance to synthetic pyrethroids among buffalo flies, zeta-cypermethrin pour-on can be expected to give good control for 4 weeks.
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Affiliation(s)
- J T Rothwell
- Elanco Animal Health, West Ryde, New South Wales
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13
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Bock RE, Rodwell BJ, McGowan M. Detection of calves persistently infected with bovine pestivirus in a sample of dairy calves in south-eastern Queensland. Aust Vet J 1997; 75:656-9. [PMID: 9325544 DOI: 10.1111/j.1751-0813.1997.tb15364.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVE To determine the proportion and incidence of calves persistently infected with bovine pestivirus in calves (n = 1521) supplied to the Tick Fever Research Centre and to assess the test regime to detect calves persistently infected with bovine pestivirus. DESIGN Calves, 1 to 6 weeks old, selected for use in the production of the tick fever vaccine were collected from 21 properties in 56 separate groups between October 1990 and December 1996. Each group was examined for the presence of calves persistently infected with bovine pestivirus. PROCEDURE All calves were routinely tested for antibody to bovine pestivirus and bovine pestivirus antigen using a serum neutralisation test and an antigen-capture ELISA, respectively. Pooled lymphocyte samples from calves were also monitored for bovine pestivirus by inoculation of sheep. Whole herd testing was carried out in eight herds, using a serum neutralisation test as a screen test followed by an antigen-capture ELISA of cattle with a serum neutralisation test titre of less than 32. RESULTS Fourteen of the 1521 calves tested (0.9%), were detected as persistently infected and the incidence ranged from 0.0 to 3.0% per year over 6 years. Persistently infected calves were found in 13 of the 59 groups and originated from 7 of the 21 herds used. In whole herd testing on the properties of origin, cattle persistently infected with bovine pestivirus were detected in four of the eight herds tested. CONCLUSIONS The proportion of calves persistently infected with bovine pestivirus is similar to that in other countries and indicates that bovine pestivirus could be a significant cause of economic loss in Australian cattle herds. In detecting calves persistently infected with bovine pestivirus, the combination of sheep inoculation, paired antigen-capture ELISA and serum neutralisation tests appeared to be highly sensitive and specific.
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Affiliation(s)
- R E Bock
- Tick Fever Research Centre, Queensland Department of Primary Industries, Wacol.
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Bock RE, de Vos AJ, Kingston TG, McLellan DJ. Effect of breed of cattle on innate resistance to infection with Babesia bovis, B bigemina and Anaplasma marginale. Aust Vet J 1997; 75:337-40. [PMID: 9196820 DOI: 10.1111/j.1751-0813.1997.tb15706.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE To assess the innate resistance of naive Bos taurus, Bos taurus cross Bos indicus and Bos indicus cattle to virulent Babesia bovis, B bigemina and Anaplasma marginale parasites. DESIGN Groups of 10, pure B indicus, 1/2 B indicus cross, 1/4 B indicus cross and pure B taurus steers were infected with virulent B bovis, B bigemina and A marginale parasites [corrected]. PROCEDURE Sequential infections were carried out by intravenous inoculation of infected blood containing 1 x 10(8) parasites of B bovis, followed by B bigemina and then A marginale. To assess resistance, measurements were made of parasitaemia, rectal temperature, packed cell volume and the number within a group requiring chemotherapy to control infection. There was a recovery period between each infection. RESULTS Infection with B bovis showed that pure B indicus steers were significantly more resistant to B bovis infection than the other groups, with none of this group requiring treatment. There was no significant difference between 1/2 B indicus cross and 1/4 B indicus cross with 30% and 20%, respectively, of steers in these groups requiring treatment [corrected]. The pure B taurus steers were significantly more affected then those in the other three groups with 80% requiring treatment. Infections of B bigemina produced a mild response in comparison to that of B bovis and none of the steers required treatment. However, the pure B taurus group was significantly more affected than the other three groups for all other measurements. After the A marginale infection, B indicus steers were moderately affected with 50% requiring treatment, whereas 70% of the 1/2 B indicus group, 80% of the 1/4 B indicus cross group and 100% of the pure B taurus group required treatment [corrected]. CONCLUSIONS All breeds of cattle, ranging from pure B indicus to pure B taurus may be at risk of severe disease if exposed to virulent A marginale. The results confirm that pure B indicus cattle are relatively resistant to B bovis, but there could be a significant risk of severe mortalities if cross-bred herds are exposed to virulent infection.
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Affiliation(s)
- R E Bock
- Tick Fever Research Centre, Wacol, Queensland.
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