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On the etiology of an outbreak of winter dysentery in dairy cows in Brazil
Brand?o, Paulo E.;Villarreal, Laura Y.B.;Gregori, F.;Souza, Silvio L.P. de;Lopes, Marco A.E.;Gomes, Cleise R.;Sforsin, Angelo J.;Sanches, Alexandre A.;Rosales, Cesar A.R.;Richtzenhain, Leonardo J.;Ferreira, Antonio J.P.;Jerez, José A.;
Pesquisa Veterinária Brasileira , 2007, DOI: 10.1590/S0100-736X2007001000002
Abstract: winter dysentery (wd) is a seasonal infectious disease described worldwide that causes a marked decrease in milk production in dairy cows. in the northern hemisphere, where the disease is classically recognized, bovine coronavirus (bcov) has been assigned as a major etiologic agent of the disease. nonetheless, in the southern hemisphere, an in-deep etiological survey on wd cases had not been carried out. this study aimed to survey for bcov by nested-rt-pcr, rotavirus by polyacrylamide gel electrophoresis (page) and elisa, bacteria by classical bacteriological methods and pcr for virulence factors and parasites by sugar flotation test on fecal samples of 21 cows from a farm during an outbreak of wd in s?o paulo state, southeastern brazil. bcov was detected in all 21 samples, while rotavirus was detected in two symptomatic cows. escherichia coli, yersinia intermedia, providencia rustigianii proteus penneri, klebsiella terrigena and enterobacter aglomerans were detected in samples from both asymptomatic and healthy cows in different associations. the study of e. coli virulence factors revealed that the strains isolated were all apathogenic. cysts of eimeria sp. and eggs of strongyloidea were detected at low numbers in four of the symptomatic cows, with one co-infestation. these results suggest bcov as the main etiologic agent of the cases of wd in brazil, a conclusion that, with the clinical and epidemiological patterns of the disease studied herein, match those already described elsewhere. these findings give basis to the development of preventive measures and contribute to the understanding of the etiology of wd.
AISLAMIENTO DE CORONAVIRUS BOVINO POR PRIMERA VEZ EN CUBA
Betancourt,A; Rodríguez,Edisleidy; Relova,Damarys; Barrera,Maritza;
Revista de Salud Animal , 2007,
Abstract: faecal samples were tested for bovine coronavirus by means of agglutination of hamster erythrocytes and hemagglutination inhibition. isolation of bovine coronavirus was carried out in monolayers of primary culture of calf kidney, using faecal samples from dairy cows with clinical signs similar to winter dysentery. when isolated, they were submitted to seroneutralization with anti-bovine coronavirus serum. these isolates were confirmed to be positive, once being neutralized.
An outbreak of acute bovine mastitis caused by Klebsiella pneumoniae in a dairy herd
Silva, N.;Costa, G.M.;
Arquivo Brasileiro de Medicina Veterinária e Zootecnia , 2001, DOI: 10.1590/S0102-09352001000400001
Abstract: an outbreak of coliform mastitis is described in a dairy herd from the state of rio de janeiro, brazil. during a four-month period 14 fatal cases of klebsiella pneumoniae-related mastitis were observed in a herd of 104 lactating cows. the symptoms included peracute enterotoxemia in which the cows died 6 to 12 h after the detection of mastitis by cmt. staphylococcus aureus andstreptococcus agalactiae streptococcus agalactiae were also isolated although could not be associated with cases of acute fatal mastitis. milking practices were also evaluated. the milking machine was being used correctly and adequate precautions for hygiene and pre-milking and post-milking teat dipping were used. the organism was sensitive to gentamicin. therapy for acute toxic mastitis required early action for the treatment of infections, involving corticosteroids and fluid therapy. the use of a klebsiella vaccine produced from the microorganisms isolated from the herd, associated with hygiene measures, resulted in the control of the outbreak.
An outbreak of acute bovine mastitis caused by Klebsiella pneumoniae in a dairy herd  [cached]
Silva N.,Costa G.M.
Arquivo Brasileiro de Medicina Veterinária e Zootecnia , 2001,
Abstract: An outbreak of coliform mastitis is described in a dairy herd from the State of Rio de Janeiro, Brazil. During a four-month period 14 fatal cases of Klebsiella pneumoniae-related mastitis were observed in a herd of 104 lactating cows. The symptoms included peracute enterotoxemia in which the cows died 6 to 12 h after the detection of mastitis by CMT. Staphylococcus aureus and Streptococcus agalactiae Streptococcus agalactiae were also isolated although could not be associated with cases of acute fatal mastitis. Milking practices were also evaluated. The milking machine was being used correctly and adequate precautions for hygiene and pre-milking and post-milking teat dipping were used. The organism was sensitive to gentamicin. Therapy for acute toxic mastitis required early action for the treatment of infections, involving corticosteroids and fluid therapy. The use of a Klebsiella vaccine produced from the microorganisms isolated from the herd, associated with hygiene measures, resulted in the control of the outbreak.
AN OUTBREAK OF FOOT AND MOUTH DISEASE IN A HERD OF CROSSBRED CATTLE  [cached]
Rashid Ahmad, Javaid Iqbal and Ghu1am Akbar1
Pakistan Veterinary Journal , 2002,
Abstract: During the months of December 200 I and January 2002, an outbreak of Foot and Mouth disease (Foot and Mouth Disease type-A virus) was recorded in a crossbred dairy herd at Livestock Experiment Station, Qadirabad. The sick animals showed only the oral lesions except one, which developed foot lesions after 10 days. The overall morbidity rate was 52.13% while the same was recorded as 7.95, 14.06, 97.36, 80.14, 62.68, 62.68, 62.50, and 7.14% in milking cows, dry cows, male young stock, female young stock, male sucklers, female sucklers and bullocks, respectively. Recovery was noticed on seventh day from the onset of out break. No mortality was recorded.
Outbreak of botulism in a dairy herd in Turkey
S Senturk, H Cihan
Irish Veterinary Journal , 2007, DOI: 10.1186/2046-0481-60-8-481
Abstract: Botulism is caused by a neurotoxin produced by Clostridium botulinum, a gram-positive, spore-forming anaerobe. Botulinum toxin is an exotoxin produced during the growth and autolysis phase of the organism under anaerobic conditions [12,14]. Eight known botulinum toxins, A, B, Ca, Cb, D, E, F and G, have been identified. Disease in cattle is produced primarily by types C and D. Clostridium botulinum types C and D produce potent toxins in carrion, feed contaminated with dead rodents, birds or reptiles, or any rotting material [12,14,1]. This study is the first confirmation, by direct toxin isolation, of Clostridium botulinum type C and Clostridium botulinum type D in cattle, in Turkey.The study was conducted on a Holstein Friesian breeding farm near the town of Bandirma in Balikesir. The herd consisted of 105 cattle. Clinically, 26 cattle including milking cows were found to be suffering from different degrees of suspected botulism. They ranged in age from four to eight years and had been ill for between two and eight days. A routine clinical examination of the animals, including body temperature, pulse, respiratory rates and ruminal movements, was performed. The neurological examination included an assessment of each affected animal's mental status, gait, pupillary light reflexes, anal reflexes, tongue reflexes, swallowing reflexes, tail tone and sensitivity to pricking with a needle. In the detailed history, the owner reported that the milking cows' feed, in addition to grain, haylage and silage, included ensiled poultry litter. It was reported that dry cows, heifers and calves were unaffected. These animals were fed different rations, without poultry litter. Routine haematological values, including haematocrit, haemoglobin, erythrocyte, total white cell and platelet counts, were determined by a haemocell counter (Cell Dyn 3500; Abbott Inc., USA). The concentrations of serum urea, creatinine, aspartate aminotransferase (AST), creatinine kinase (CK) and, potassium (K
Leptospirosis Seroconversion During an Abortion Outbreak in a Mexican Hairless Swine Herd
M. A. Cisneros-Puebla,D. Mota-Rojas,L. P. Moles-Cervantes,R.Ram?rez-Necoechea,M. Alonso-Spilsbury
Journal of Animal and Veterinary Advances , 2012,
Abstract: A herd of Mexican Hairless Swine, maintained in an agro-silvi-culture pasture in the village of Chapa de Mota, Mexico, underwent a serological study after one of the sows aborted a litter showing fever. Blood samples were drawn from thirty-four animals in reproductive stage, which then underwent a treatment, based on a streptomycin dose of 25 mg/kg live weight during five days. Twenty-eight samples were taken 15 days after the herd either farrowed or aborted. Seroconversion was found in five animals with a serovar of hardjo H 89 origin. One of the animals aborted after seventy-eight days of gestation; in all the cases there was a negative increase of between 1:200 to 1:800 titres, while the serovar bratislava presented titres in six animals. In two cases the seroconversion went from a negative to a 1:200, while one of the pigs miscarried on the 77th day of pregnancy, and two other animals went from a titre 1:100 to 1:200. Another sow lost a litter on day 84, and in the last two animals the titre was maintained at 1:100, though one of the pigs aborted on the 86th day. This paper constitutes the first report of an outbreak of abortions in the Mexican Hairless Swine caused by Leptospira interrogans serovars bratislava and hardjo.
Identification of turkey astrovirus and turkey coronavirus in an outbreak of Poult Enteritis and Mortality Syndrome
Villarreal, LYB;Assayag, MS;Brand?o, PE;Chacón, JLV;Bunger, AND;Astolfi-Ferreira, CS;Gomes, CR;Jones, RC;Ferreira, AJP;
Revista Brasileira de Ciência Avícola , 2006, DOI: 10.1590/S1516-635X2006000200010
Abstract: this article reports a survey on turkey astrovirus (tastv) and turkey coronavirus (tcov) infections with rt-pcr in 17 turkey flocks affected by acute enteritis and two apparently normal turkey flocks located in the southeastern region of brazil by pcr (tastv and tcov). seven out of the 17 affected flocks were positive for tastv and 14 for tcov, with seven co-infections. in one of the two apparently normal flocks, a tastv-tcov co-infection was found. although a definitive association of these agents and the signs can not be made, the implications of these findings are discussed.
Clinical aspects of an outbreak of papillomatous digital dermatitis in a dairy cattle herd : case report  [cached]
I. Yeruham,S. Perl
Journal of the South African Veterinary Association , 2012, DOI: 10.4102/jsava.v69i3.830
Abstract: Digital skin lesions and lameness of several weeks duration, with a morbidity rate of 28.3 %, was reported in a group of 60 Holstein-Israeli dairy cows in various stages of lactation. A clinical survey was performed to monitor recovery and to confirm eradication of bovine papillomatous digital dermatitis in the herd. The combined effects of intensive individual treatment of the 4 lame cattle with procaine penicillin and metronidazole, and subjecting all animals in the herd to a foot bath with a solution composed of formaldehyde and sodium hydroxide twice a week for 12 weeks, were found to achieve a dramatic positive response in all affected cows in the herd. During a 1-year follow-up period no recurrence and/or new cases have been diagnosed.
Predicting the Herd Immunity Threshold during an Outbreak: A Recursive Approach  [PDF]
Nathan T. Georgette
PLOS ONE , 2009, DOI: 10.1371/journal.pone.0004168
Abstract: Background The objective was to develop a novel algorithm that can predict, based on field survey data, the minimum vaccination coverage required to reduce the mean number of infections per infectious individual to less than one (the Outbreak Response Immunization Threshold or ORIT) from up to six days in the advance. Methodology/Principal Findings First, the relationship between the rate of immunization and the ORIT was analyzed to establish a link. This relationship served as the basis for the development of a recursive algorithm that predicts the ORIT using survey data from two consecutive days. The algorithm was tested using data from two actual measles outbreaks. The prediction day difference (PDD) was defined as the number of days between the second day of data input and the day of the prediction. The effects of different PDDs on the prediction error were analyzed, and it was found that a PDD of 5 minimized the error in the prediction. In addition, I developed a model demonstrating the relationship between changes in the vaccination coverage and changes in the individual reproduction number. Conclusions/Significance The predictive algorithm for the ORIT generates a viable prediction of the minimum number of vaccines required to stop an outbreak in real time. With this knowledge, the outbreak control agency may plan to expend the lowest amount of funds required stop an outbreak, allowing the diversion of the funds saved to other areas of medical need.
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