The clinical diagnosis of cattle diseases /

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Updated estimates of the costs associated with thirty four endemic livestock diseases in Great Britain: A note

This Note outlines the further development of a system of models for the estimation of the costs of livestock diseases first presented by Bennett (2003). The models have been developed to provide updated and improved estimates of the costs associated with 34 endemic diseases of livestock in Great Britain, using border prices and including assessments of the impact of diseases on human health and animal welfare. Results show that, of the diseases studied, mastitis has the highest costs for cattle diseases, enzootic abortion for sheep diseases, swine influenza for pig diseases and salmonellosis for poultry diseases.

Design and formative evaluation of an information kiosk on cattle health for landless cattle owners

This paper describes and analyses the experience of designing, installing and evaluating a farmer-usable touch screen information kiosk on cattle health in a veterinary institution in Pondicherry. The contents of the kiosk were prepared based on identified demands for information on cattle health, arrived at through various stakeholders meetings. Information on these cattle diseases and conditions affecting the livelihoods of the poor was provided through graphics, text and audio back-up, keeping in mind the needs of landless and illiterate poor cattle owners. A methodology for kiosk evaluation based on the feedback obtained from kiosk facilitator, critical group reflection and individual users was formulated. The formative evaluation reveals the potential strength this ICT has in transferring information to the cattle owners in a service delivery centre. Such information is vital in preventing diseases and helps cattle owners to present and treat their animals at an early stage of disease condition. This in turn helps prevent direct and indirect losses to the cattle owners. The study reveals how an information kiosk installed at a government institution as a freely accessible source of information to all farmers irrespective of their class and caste can help in transfer of information among poor cattle owners, provided periodic updating, interactivity and communication variability are taken care of. Being in the veterinary centre, the kiosk helps stimulate dialogue, and facilitates demand of services based on the information provided by the kiosk screens.

An enzyme-linked immunosorbent assay (elisa) for the detection of antibodies against babesia boris in cattle

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Skin test and tick immune status in susceptible and resistant cattle in Brazil

A cutaneous hypersensitivity test (CHT) was used to correlate host resistance to ticks and type of reaction elicited to unfed larval extract-ULE of the cattle tick Boophilus microplus in European and Indian cattle. Twenty calves were separated into four groups of five animals each: naïve or preinfested Indian or European cattle. CHT was induced by intradermal inoculation of 0.1 ml of ULE cattle tick B. microplus (50 μg protein) in the calf ear. Ear thickness was measured using calipers before and 10 min, 1, 2, 6, 18, 24, 48, 72, 96, and 144 h postinoculation (PI). Preinfested European calves showed only an immediate type reaction with maximum response (75% increase in ear thickness) at 10 min PI. On the other hand, preinfested Indian calves presented an immediate response with maximum reaction (70% increase in ear thickness) between 10 min and one hour PI, and a delayed type reaction at 72 h PI (60% increase in ear thickness). These results point out the crucial role of the cellular immune response of cattle in the expression of resistance to cattle tick B. microplus. Skin test might be useful in the ranking of cattle according to the susceptibility/resistance to ticks.

Araçatuba virus: A vaccinialike virus associated with infection in humans and cattle

We describe a vaccinialike virus, Araçatuba virus, associated with a cowpoxlike outbreak in a dairy herd and a related case of human infection. Diagnosis was based on virus growth characteristics, electron microscopy, and molecular biology techniques. Molecular characterization of the virus was done by using polymerase chain reaction amplification, cloning, and DNA sequencing of conserved orthopoxvirus genes such as the vaccinia growth factor (VGF), thymidine kinase (TK), and hemagglutinin. We used VGF-homologous and TK gene nucleotide sequences to construct a phylogenetic tree for comparison with other poxviruses. Gene sequences showed 99% homology with vaccinia virus genes and were clustered together with the isolated virus in the phylogenetic tree. Araçatuba virus is very similar to Cantagalo virus, showing the same signature deletion in the gene. Araçatuba virus could be a novel vaccinialike virus or could represent the spread of Cantagalo virus.

Foamy macrophages in the liver of cattle fed Brachiaria brizantha hay

Liver and lymph nodes injuries characterized by clusters of foamy macrophages, some of them containing birefringent crystals, were observed in cattle fed on Brachiaria brizantha hay. The cattle were from an experimental group poisoned with Senecio brasiliensis known to cause hepatic fibrosis and hepatocyte megalocytosis. One of the animals developed photosensitivity but the exact cause wasn't determined since both plants were fed. The foamy macrophages were present from the 30th d of feeding. Early appearance of these lesions may be particular to the animal specie used or due to the presence of both toxic plants.

Effects of vaccination against reproductive diseases on reproductive performance of beef cows submitted to fixed-timed AI in Brazilian cow-calf operations

The objectives were to assess incidence of pregnancy losses, associate this outcome with immunization programs against reproductive diseases, and evaluate the effects of vaccination against bovine herpesvirus-1 (BoHV-1), bovine viral diarrhea virus (BVDV), and Leptospira spp., on reproductive efficiency of Brazilian cow-calf operations. In experiment 1, 7614 lactating Nelore cows from 18 ranches were assigned to the same estrus synchronization and fixed-time AI protocol (ESFTAI; Days -11 to 0). Pregnancy status was determined with transrectal ultrasonography on Days 30 and 120 after AI. Pregnancy loss was deemed to have occurred when cows were pregnant on Day 30 but nonpregnant on Day 120. Incidence of pregnancy loss across all ranches was 4.1%; pregnancy losses were detected (P < 0.10) in 14 ranches but not detected (P > 0.11) in four ranches. Pregnancy loss was lower (P ≤ 0.02) in ranches that vaccinated against BoHV-1, BVDV, and Leptospira spp. compared with ranches that did not vaccinate, or only vaccinated against Leptospira spp. In experiments 2 and 3, lactating Nelore cows (N = 1950 and 2793, respectively) from ranches that did not have a history of vaccinating against reproductive diseases (experiment 2), or only vaccinated against Leptospira spp. (experiment 3), were assigned to the same ESFTAI used in experiment 1. Within each ranch, cows received (VAC) or not (CON) vaccination against BoHV-1, BVDV, and Leptospira spp. at the beginning of the ESFTAI (Day -11) and 30 days after (Day 41) AI. In experiment 2, VAC cows had greater (P ≤ 0.05) pregnancy rates compared with CON on Days 30 and 120. In experiments 2 and 3, pregnancy loss was reduced (P ≤ 0.03) in primiparous VAC cows compared with CON cohorts. In experiment 4, 367 primiparous, lactating Nelore cows previously vaccinated against Leptospira spp. were assigned to the same ESFTAI used in experiment 1. Cows received VAC, or the same vaccine 30 days before (Day -41) and at the beginning (Day -11) of the ESFTAI (PREVAC). Pregnancy rates on Days 30 and 120 were greater (P ≤ 0.05) in PREVAC cows compared with VAC cows. In conclusion, pregnancy losses affected reproductive and overall efficiency of Brazilian cow-calf operations, and might be directly associated with BoHV-1, BVDV, and Leptospira spp. infections. Hence, vaccinating cows against these pathogens, particularly when both doses are administered before fixed-time AI, improved reproductive performance in Brazilian cow-calf systems. © 2013 Elsevier Inc.

Babesia bovis infection in cattle in the southwestern Brazilian Amazon

The present study provides the first epidemiological data on infection with Babesia bovis in cattle raised in the southwestern Brazilian Amazon. Blood clot samples were filtered through nylon cloth before being submitted to DNA extraction. PCR and nested-PCR were applied to assess the frequency of infection with B. bovis in calves with ages from 4 to 12 months bred in 4 microregions each in the states of Rondônia and Acre. After the DNA was extracted from the samples, the infection in cattle was investigated by amplification of the rap1 gene from B. bovis. The DNA amplification results revealed a frequency of infection with B. bovis of 95.1% (272/286) in the samples from Rondônia and 96.1% (195/203) in those from Acre. The high frequency of B. bovis infection in the animals with ages from 4 to 12 months indicates a situation of enzootic stability in the regions studied. The infection rates are comparable to those detected by immunodiagnostic techniques in other endemic regions of Brazil. © 2012 Elsevier GmbH.

Persistent efficacy of 3.5% doramectin compared to 3.15% ivermectin against gastrointestinal nematodes in experimentally-infected cattle in Brazil

The present study aimed to evaluate the persistent efficacy of a 3.5% doramectin* (700μg/kg) formulation compared to 3.15% ivermectin** (630μg/kg) treatment, administered subcutaneously at a dose of 1mL/50kg body weight in cattle experimentally infected with gastrointestinal nematodes. Seventy-two male crossbred Holstein cattle that were negative for helminth infection were divided into nine groups. Treatments of 3.5% doramectin (Groups 2, 4, 6 and 8) and 3.15% ivermectin (Groups 3, 5, 7 and 9) were administered on days 49, 42, 35 and 28 prior to challenge with infectious nematode larvae (L3). Animals in the control group (Group 1) received saline solution on day 49 before challenge. Beginning on day zero, each animal received 50mL orally of a mixed culture containing approximately 3,000 third stage larvae (L3) of Haemonchus (60%), Oesophagostomum (20%), Cooperia (15%) and Trichostrongylus (5%) for seven consecutive days, resulting in a total challenge of 21,000 larvae/animal. Due to the large number of cattle, autopsies were performed between days 28 and 35 after the last day of inoculation. The formulation containing doramectin (700 mcg/kg) achieved persistent efficacy against H. placei and C. punctata for 49 and 35days, respectively. The persistent efficacy of ivermectin (630 mcg/kg) against H. placei lasted for 49days, but this treatment was ineffective against C. punctata. Both formulations demonstrated persistent efficacy against T. axei for 49days. The persistent efficacy of doramectin (700 mcg/kg) and ivermectin (630 mcg/kg) lasted for 49 and 42days against O. radiatum, respectively. © 2012 Elsevier Ltd.

Investigating the potential of reported cattle mortality data in Switzerland for syndromic surveillance

Systems for the identification and registration of cattle have gradually been receiving attention for use in syndromic surveillance, a relatively recent approach for the early detection of infectious disease outbreaks. Real or near real-time monitoring of deaths or stillbirths reported to these systems offer an opportunity to detect temporal or spatial clusters of increased mortality that could be caused by an infectious disease epidemic. In Switzerland, such data are recorded in the "Tierverkehrsdatenbank" (TVD). To investigate the potential of the Swiss TVD for syndromic surveillance, 3 years of data (2009-2011) were assessed in terms of data quality, including timeliness of reporting and completeness of geographic data. Two time-series consisting of reported on-farm deaths and stillbirths were retrospectively analysed to define and quantify the temporal patterns that result from non-health related factors. Geographic data were almost always present in the TVD data; often at different spatial scales. On-farm deaths were reported to the database by farmers in a timely fashion; stillbirths were less timely. Timeliness and geographic coverage are two important features of disease surveillance systems, highlighting the suitability of the TVD for use in a syndromic surveillance system. Both time series exhibited different temporal patterns that were associated with non-health related factors. To avoid false positive signals, these patterns need to be removed from the data or accounted for in some way before applying aberration detection algorithms in real-time. Evaluating mortality data reported to systems for the identification and registration of cattle is of value for comparing national data systems and as a first step towards a European-wide early detection system for emerging and re-emerging cattle diseases.

Use of immunosorbent-purified antigens of Fasciola hepatica in enzyme immunoassays

A monoclonal antibody specific for the T1 tegumental antigen of Fasciola hepatica was used as a solid-phase immunosorbent for the purification of T1 antigen from homogenised mature F hepatica. Material fractionated by this technique was successfully used in enzyme-linked immunoassays to detect antibodies to F hepatica in sera from sheep and cattle. Species differences in response to infection by F hepatica were demonstrated.

Characterisation and comparison of bovine RNA polymerase III promoters for RNA interference

The characterisation of novel bovine RNA polymerase III promoters for the expression of short hairpin RNAs for gene silencing resulted in the identification of a highly efficient promoter sequence. The replication of bovine viral diarrhea virus was them suppressed using short hairpin RNAs expressed form this promoter in vitro.