The Duration of the Effects of Repeated Widespread Badger Culling on Cattle Tuberculosis Following the Cessation of Culling

Background: In the British Isles, control of cattle tuberculosis (TB) is hindered by persistent infection of wild badger (Meles meles) populations. A large-scale field trial—the Randomised Badger Culling Trial (RBCT)—previously showed that widespread badger culling produced modest reductions in cattle TB incidence during culling, which were offset by elevated TB risks for cattle on adjoining lands. Once culling was halted, beneficial effects inside culling areas increased, while detrimental effects on adjoining lands disappeared. However, a full assessment of the utility of badger culling requires information on the duration of culling effects. Methodology/Principal Findings: We monitored cattle TB incidence in and around RBCT areas after culling ended. We found that benefits inside culled areas declined over time, and were no longer detectable by three years post-culling. On adjoining lands, a trend suggesting beneficial effects immediately after the end of culling was insignificant, and disappeared after 18 months post-culling. From completion of the first cull to the loss of detectable effects (an average five-year culling period plus 2.5 years post-culling), cattle TB incidence was 28.7% lower (95% confidence interval [CI] 20.7 to 35.8% lower) inside ten 100 km2 culled areas than inside ten matched no-culling areas, and comparable (11.7% higher, 95% CI: 13.0% lower to 43.4% higher, p = 0.39) on lands #2 km outside culled and no-culling areas. The financial costs of culling an idealized 150 km2 area would exceed the savings achieved through reduced cattle TB, by factors of 2 to 3.5. Conclusions/Significance: Our findings show that the reductions in cattle TB incidence achieved by repeated badger culling were not sustained in the long term after culling ended and did not offset the financial costs of culling. These results, combined with evaluation of alternative culling methods, suggest that badger culling is unlikely to contribute effectively to the control of cattle TB in Britain.

Monitoring of Transmission of Tuberculosis between Wild Boars and Cattle: Genotypical Analysis of Strains by Molecular Epidemiology Techniques

An epidemiological survey for the monitoring of bovine tuberculosis transmission was carried out in western Liguria, a region in northern Italy. Fifteen Mycobacterium bovis strains were isolated from 63 wild boar samples (62 from mandibular lymph nodes and 1 from a liver specimen). Sixteen mediastinal lymph nodes of 16 head of cattle were collected, and 15 Mycobacterium bovis strains were subsequently cultured. All M. bovisstrains isolated from cattle and wild boars were genotyped by spoligotyping and by restriction fragment length polymorphism (RFLP) analysis with the IS6110 and IS1081 probes. All M. bovis strains showed the typical spoligotype characterized by the absence of the 39 to 43 spacers in comparison with the number in M. tuberculosis. A total of nine different clusters were identified by spoligotyping. The largest cluster included 9 strains isolated from wild boars and 11 strains isolated from cattle, thus confirming the possibility of transmission between the two animal species. Fingerprinting by RFLP analysis with the IS6110 probe showed an identical single-band pattern for 29 of 30 strains analyzed, and only 1 strain presented a five-band pattern. The use of IS1081 as a second probe was useful for differentiation of M. bovis from M. bovis BCG but not for differentiation among M. bovis strains, which presented the same undifferentiated genomic profile. In relation to the epidemiological investigation, we hypothesized that the feeding in pastures contaminated by cattle discharges could represent the most probable route of transmission of M. bovis between the two animal species. In conclusion, our results confirmed the higher discriminatory power of spoligotyping in relation to that of RFLP analysis for the differentiation of M. bovis genomic profiles. Our data showed the presence of a common M. bovis genotype in both cattle and wild boars, confirming the possible interspecies transmission of M. bovis.

Emergence of Diseases From Wildlife Reservoirs

Interest in the epidemiology of emerging diseases of humans and livestock as they relate to wildlife has increased greatly over the past several decades. Many factors, most anthropogenic, have facilitated the emergence of diseases from wildlife. Some livestock diseases have ‘‘spilled over’’ to wildlife and then ‘‘spilled back’’ to livestock. When a population is exposed to an infectious agent, depending on an interaction of factors involving the host, agent, and environment, the population may be resistant to infection or may become a dead-end host, a spillover host, or a maintenance host. Each exposure is unique; the same species of host and agent may respond differently in different situations. Management actions that affect the environment and behavior of a potential host animal may allow the emergence of a new or as yet undetected disease. There are many barriers in preventing, detecting, monitoring and managing wildlife diseases. These may include political and legal hurdles, lack of knowledge about many diseases of wildlife, the absence of basic data on wildlife populations, difficulties with surveillance, and logistical constraints. Increasing interaction between wildlife and humans or domestic animals may lead to disease emergence and require innovative methods and strategies for disease surveillance and management in wildlife.

Molecular confirmation of ovine herpesvirus 2-induced malignant catarrhal fever lesions in cattle from Rio Grande do Norte, Brazil

Molecular findings that confirmed the participation of ovine herpesvirus 2 (OVH-2) in the lesions that were consistent with those observed in malignant catarrhal fever of cattle are described. Three mixed-breed cattle from Rio Grande do Norte state demonstrated clinical manifestations that included mucopurulent nasal discharge, corneal opacity and motor incoordination. Routine necropsy examination demonstrated ulcerations and hemorrhage of the oral cavity, corneal opacity, and lymph node enlargement. Significant histopathological findings included widespread necrotizing vasculitis, non-suppurative meningoencephalitis, lymphocytic interstitial nephritis and hepatitis, and thrombosis. PCR assay performed on DNA extracted from kidney and mesenteric lymph node of one animal amplified a product of 423 base pairs corresponding to a target sequence within the ovine herpesvirus 2 (OVH-2) tegument protein gene. Direct sequencing of the PCR products, from extracted DNA of the kidney and mesenteric lymph node of one cow, amplified the partial nucleotide sequences (423 base pairs) of OVH-2 tegument protein gene. Blast analysis confirmed that these sequences have 98-100% identity with similar OVH-2 sequences deposited in GenBank. Phylogenetic analyses, based on the deduced amino acid sequences, demonstrated that the strain of OVH-2 circulating in ruminants from the Brazilian states of Rio Grande do Norte and Minas Gerais are similar to that identified in other geographical locations. These findings confirmed the active participation of OVH-2 in the classical manifestations of sheep associated malignant catarrhal fever.

Bioethical Aspects Across Medicine: The Care of Cardiovascular Diseases in Brazil

Bioethics applied to medicine extrapolates the traditional medical concepts of non-maleficence (primum non nocere) and beneficence (bonum facere) and regards to justice, autonomy, equity, protection, compassion and humanization, not considering people just like patients, but understanding the complex existence of each single person. Worldwide, the morbidity and mortality indices regarding to diseases of heart and blood vessels became progressively grater. For countries in development, like Brazil, these numbers are even more expressive and this increase trend seems to be caused by wider exposition of population to some risk factors. This article broaches an intersection between bioethics and medicine, focusing the reality of cardiovascular diseases in Brazil and the necessity of doctors to base their behavior in bioethical paradigms.

Diagnostic significance of Neospora caninum DNA detected by PCR in cattle serum

A nested PCR that successfully detected Neospora caninum DNA in serum of cattle was used for investigation of selected abortion cases and in a study of healthy pregnant cows at an abattoir. N. caninum DNA was not detected in serum from antibody positive dams that aborted due to N. caninum, but was present in serum of some antibody negative dams that aborted due to other causes. N. caninum DNA was also found in the serum of about half of the animals that aborted of undetermined cause, but was not detected in cow sera from two beef cattle herds in Western Australia with no recent history of abortion. In the abattoir study of 79 dams and their foetuses N. caninum DNA was found in serum of 3 dams and in material from 11 foetuses. The majority of the cows and all foetuses were antibody negative. Our findings suggest that there is no obvious relationship between the presence or absence of N. caninum DNA in serum and the presence of antibodies to N. caninum in dams, the presence of N. caninum DNA in foetuses or abortion due to N. caninum. This is the first report of the detection of N. caninum DNA in serum of cattle rather than the white blood cell fraction. It indicates the presence of free tachyzoites and/or parasite DNA in circulation. The results suggest that persistent infection in the absence of antibodies is a possible outcome of N. caninum infection. Infection of foetuses in the absence of antibodies supports the possibility of persistent infection due to immunotolerance to an early in utero infection. It is therefore important to test for N. caninum DNA as well as antibodies for the detection of exposed and/or infected animals. However, the presence or absence of N. caninum antibodies or DNA did not support nor exclude N. caninum as the cause of abortion. Additional criteria are required for a positive diagnosis of abortion caused by N. caninum.

Microarray based study on virulence-associated genes and resistance determinants of Staphylococcus aureus isolates from cattle

Staphylococcus aureus is a common pathogen which can colonise and infect not only man, but also domestic animals. Especially, infection of cattle is of high economic relevance as S. aureus is an important causal agent of bovine mastitis. In the present contribution, a DNA microarray was applied for the study of 144 different gene targets, including resistance genes and genes encoding exotoxins, in S. aureus isolated from cows. One hundred and twenty-eight isolates from Germany and Switzerland were tested. These isolates were assigned to 20 different strains and nine clonal complexes. The majority of isolates belonged either to apparently closely related clonal complexes 8, 25, and 97 (together 34.4%) or were related to the sequenced bovine strain RF122 (48.4%). Notable characteristics of S. aureus of bovine origin are the carriage of intact haemolysin beta (in 82% of isolates tested), the absence of staphylokinase (in 89.1%), the presence of allelic variants of several exotoxins such as toxic shock syndrome toxin and enterotoxin N, and the occurrence of the leukocidin lukF-P83/lukM (in 53.1%). Two isolates were methicillin-resistant S. aureus (MRSA). One of them was a clonal complex 8 MRSA related to the epidemic MRSA strain Irish 01. The other one belonged to ST398/spa-type 34 resembling a newly emerging MRSA strain which has been described to occur in humans as well as in domestic animals. The presence of these two strains highlights the possibility of transfers of S. aureus strains between different host species.

Integration of Pasturing Systems for Cattle Finishing Programs

A 3-year study, using 84 fall-born and 28 spring-born calves of similar genotypes, was conducted to integrate pasturing systems with drylot feeding systems. Calves were started on test following weaning in May and October. Seven treatments were imposed: 1) fall-born calves directly into feedlot; 2 and 3) fall-born calves put on pasture with or without ionophore and moved to the feedlot at the end of July; 4 and 5) fall-born calves put on pasture with or without ionophore and moved to the feedlot at the end of October; 6 and 7) spring-born calves put on pasture with or without ionophore and moved to the feedlot at the end of October. A bromegrass pasture consisting of 16 paddocks, each 1.7 acre in size, was available. Each treatment group had access to 1 paddock at a time and was rotated at approximately 3-day intervals. In the feedlot, steers were provided an 82% concentrate diet containing whole-shelled corn, ground alfalfa hay, and a protein, vitamin and mineral supplement containing ionophore and molasses. As pens of cattle reached about 1150 lb. average live weight, they were processed and carcass traits were evaluated. Pasture daily gains were highest for cattle on pasture for the longest duration (P < .03), and overall daily gains were highest for drylot cattle (P < .01) and decreased with increased time spent on pasture. Although differences among treatments existed in numerical scores for yield and quality grades (P < .05 and P < .03, respectively), all treatments provided average yield grade scores of 2 and quality grades of low Choice or higher. Use of four production costs and pricing scenarios revealed that fall-born calves placed on pasture for varying lengths of time were the most profitable (P < .04) among the treatments. Furthermore, employing a 5% price sensitivity analysis, indicated that fed-cattle selling price had great impact on profit potential and was followed in importance by feeder purchase price and corn grain price. Overall, these findings should provide significant production alternatives for some segments of the cattle feeding industry and also lend substantial credence to the concept of sustainable agriculture.

Integration of Pasturing Systems for Cattle Finishing Programs: A Progress Report

A three-year study was conducted to integrate pasturing systems with drylot feeding systems. Each year 84 fall-born and 28 spring-born calves of similar genotypes were used. Fall-born calves were started on test in May, and spring-born calves were started in October. Seven treatments were imposed: 1) fall-born calves directly into the feedlot (28 steers); 2 and 3) fall-born calves put on pasture with or without an ionophore and moved to the feedlot at the end of July (14 steers in each treatment); 4 and 5) fall-born calves put on pasture with or without an ionophore and moved to the feedlot at the end of October (14 steers in each treatment); and 6 and 7) spring-born calves put on pasture with or without an ionophore and moved to the feedlot at the end of October (14 steers in each treatment). Cattle on pasture receiving an ionophore gained faster (P=.009), but lost this advantage in drylot (P>.10). Overall, cattle started directly in the feedlot had higher gains (P<.001). Cattle receiving an ionophore on pasture had lower KPH than those that did not receive an ionophore (P<.01). Treatment influenced yield grade (P<0.001), although all treatments were YG 2. The percentage of cattle grading Prime and Choice was 75 % or higher for all treatment groups. The results show that using an ionophore improved pasture gains and that pasture treatments did not adversely influence yield and quality grades.

Cattle immunized against the pathogenic L-α-glycerol-3-phosphate oxidase of Mycoplasma mycoides subs. mycoides fail to generate neutralizing antibodies and succumb to disease on challenge

The membrane-associated enzyme L-α-glycerol-3-phosphate oxidase (GlpO) of Mycoplasma mycoides subs. mycoides (Mmm), the causal agent of contagious bovine pleuropneumonia (CBPP) has been identified as a virulence factor responsible for the release of toxic by-products such as H2O2 that mediate host cell injury. Since CBPP pathogenesis is based on host inflammatory reactions, we have determined the capacity of recombinant GlpO to generate in vivo protective responses against challenge in immunized cattle. We also investigated whether sera raised against recombinant GlpO in cattle and mice inhibit production of H2O2 by Mmm. Immunization of cattle with recombinant GlpO did not protect against challenge with a virulent strain of Mmm. Further, although both murine and bovine antisera raised against recombinant GlpO detected recombinant and native forms of GlpO in immunoblot assays with similar titres, only murine antibodies could neutralize GlpO enzymatic function. The data raise the possibility that Mmm has adapted to evade potential detrimental antibody responses in its definitive host.

Current attitudes of bovine practitioners, claw-trimmers and farmers in Switzerland to pain and painful interventions in the feet in dairy cattle.

The attitudes of bovine practitioners, claw-trimmers and farmers towards painful therapeutic claw-trimming of dairy cattle were surveyed and differences between the respondents were assessed. A total of 77 farmers and 32 claw-trimmers were interviewed, and 137 bovine practitioners completed an equivalent online survey. No veterinary consultation for common painful interventions in the feet of cattle was reported by 52% of farmers (i.e. procedures in these herds were performed without local anaesthesia). Only ≈30% of practitioners always carried out such interventions under local anaesthesia and, in general, practitioners considered pain reduction to the lowest possible level less important than did farmers. Furthermore, 47% of practitioners and 33% of claw-trimmers, compared to only 11% of farmers, agreed with the statement that the cost of pain management was a major concern for farmers. There was a particular lack of awareness by farmers regarding the obligation to carry out painful therapeutic claw-trimming under analgesia and the application of local anaesthesia during the trimming of sole ulcers was considered reasonable by significantly fewer farmers (41.6%) and claw-trimmers (46.9%), than practitioners (78.6%). Overall, the attitudes of those involved in painful therapeutic claw-trimming contrasted with Swiss national legislation and with farmer opinion on the importance of reducing pain to the lowest level possible.

Persistent infections after natural transmission of bovine viral diarrhoea virus from cattle to goats and among goats

Bovine viral diarrhoea virus (BVDV) is an economically important pathogen of cattle worldwide. Infection of a pregnant animal may lead to persistent infection of the foetus and birth of a persistently infected (PI) calf that sheds the virus throughout its life. However, BVD viruses are not strictly species specific. BVDV has been isolated from many domesticated and wild ruminants. This is of practical importance as virus reservoirs in non-bovine hosts may hamper BVDV control in cattle. A goat given as a social companion to a BVDV PI calf gave birth to a PI goat kid. In order to test if goat to goat infections were possible, seronegative pregnant goats were exposed to the PI goat. In parallel, seronegative pregnant goats were kept together with the PI calf. Only the goat to goat transmission resulted in the birth of a next generation of BVDV PI kids whereas all goats kept together with the PI calf aborted. To our knowledge, this is the first report which shows that a PI goat cannot only transmit BVD virus to other goats but that such transmission may indeed lead to the birth of a second generation of PI goats. Genetic analyses indicated that establishment in the new host species may be associated with step-wise adaptations in the viral genome. Thus, goats have the potential to be a reservoir for BVDV. However, the PI goats showed growth retardation and anaemia and their survival under natural conditions remains questionable.

Genetics of upper and lower airway diseases in the horse.

Genetic predispositions for guttural pouch tympany, recurrent laryngeal neuropathy and recurrent airway obstruction (RAO) are well documented. There is also evidence that exercise-induced pulmonary haemorrhage and infectious diseases of the respiratory tract in horses have a genetic component. The clinical expression of equine respiratory diseases with a genetic basis results from complex interactions between the environment and the genetic make-up of each individual horse. The genetic effects are likely to be due to variations in several genes, i.e. they are polygenic. It is therefore unlikely that single gene tests will be diagnostically useful in these disorders. Genetic profiling panels, combining several genetic factors with an assessment of environmental risk factors, may have greater value, but much work is still needed to uncover diagnostically useful genetic markers or even causative variants for equine respiratory diseases. Nonetheless, chromosomal regions associated with guttural pouch tympany, recurrent laryngeal neuropathy and RAO have been identified. The association of RAO with other hypersensitivities and with resistance to intestinal parasites requires further study. This review aims to provide an overview of the available data and current thoughts on the genetics of equine airway diseases.

Neurotropic astrovirus in cattle with nonsuppurative encephalitis in Europe

Encephalitis is a frequently diagnosed condition in cattle with neurological diseases. Many affected animals present with a nonsuppurative inflammatory reaction pattern in the brain. While this pattern supports a viral etiology, the causative pathogen remains unknown in a large proportion of cases. Using viral metagenomics, we identified an astrovirus (bovine astrovirus [BoAstV]-CH13) in the brain of a cow with nonsuppurative encephalitis. Additionally, BoAstV RNA was detected with reverse transcription-PCR and in situ hybridization in about one fourth (5/22 animals) of cattle with nonsuppurative encephalitis of unknown etiology. Viral RNA was found primarily in neurons and at the site of pathology. These findings support the notion that BoAstV infection is a common cause of encephalitis in cattle. Phylogenetically, BoAstV-CH13 was closely related to rare astrovirus isolates from encephalitis cases in animals and a human patient. Future research needs to be directed toward the pathogenic mechanisms, epidemiology, and potential cross-species transmission of these neurotropic astroviruses.

Prevalence of paunch calf syndrome carriers in Italian Romagnola cattle.

The term 'paunch calf syndrome' encompasses the multi-organic lethal developmental dysplasia reported in the Romagnola breed of cattle and is characterised by facial deformities, an enlarged and floating abdomen containing considerable abdominal effusion, and hepatic fibrosis. Paunch calf syndrome is caused by a missense mutation in the KDM2B gene (c.2503G>A) that is thought to lead to an amino acid exchange (p.D835N). In this study, the prevalence of carriers of the mutant KDM2B allele (and thus the frequency of the allele) was assessed in selected subpopulations of Romagnola cattle. The prevalence of carriers within top-ranked Romagnola sires over the years 2007-2012 was 29.3% (allele frequency 14.6%). In young bull calves, 30.9% were carriers with an allele frequency of 15.4%.