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An outbreak of winter dysentery caused by bovine coronavirus in a high-production dairy cattle herd from a tropical country
Takiuchi, Elisabete;Barry, Aline Fernandes;Alfieri, Alice Fernandes;Filippsen, Patrícia;Alfieri, Amauri Alcindo;
Brazilian Archives of Biology and Technology , 2009, DOI: 10.1590/S1516-89132009000700008
Abstract: bovine coronavirus (bcov) is a known cause of winter dysentery (wd) in adult cattle. the morbidity of the disease is high, that results in a significant decrease in milk production and consequently, economic losses. in the present study, we report on a classical outbreak of wd that affected a high-production holstein dairy herd raised in a tropical country. the lactating batch included 154 cows, and 138 (90%) presented diarrhea in a short (nine days) period of time. three (2%) cows died. the other batches of animals did not become ill. the evolution of the disease in the herd, including the clinical signs and epidemiological features, strongly suggested a wd case. semi-nested pcr and rflp confirmed that bcov was the cause of the infection. samples tested negative for all other enteric pathogens. this case report highlights the importance of bcov in wd even in tropical countries such as brazil.
Etiology and antimicrobial susceptibility of udder pathogens from cases of subclinical mastitis in dairy cows in Sweden
Ylva Persson, Ann-Kristin J Nyman, Ulrika Gr?nlund-Andersson
Acta Veterinaria Scandinavica , 2011, DOI: 10.1186/1751-0147-53-36
Abstract: In total, 583 quarter milk samples were collected from 583 dairy cows at 226 dairy farms from February 2008 to February 2009. The quarter milk samples were bacteriological investigated and scored using the California Mastitis Test. Staphylococci were tested for betalactamase production and presence of resistance was evaluated in all specific udder pathogens. Differences between newly infected cows and chronically infected cows were statistically investigated using logistic regression analysis.The most common isolates of 590 bacteriological diagnoses were Staphylococcus (S) aureus (19%) and coagulase-negative staphylococci (CNS; 16%) followed by Streptococcus (Str) dysgalactiae (9%), Str. uberis (8%), Escherichia (E.) coli (2.9%), and Streptococcus spp. (1.9%). Samples with no growth or contamination constituted 22% and 18% of the diagnoses, respectively. The distribution of the most commonly isolated bacteria considering only bacteriological positive samples were: S. aureus - 31%, CNS - 27%, Str. dysgalactiae - 15%, Str. uberis - 14%, E. coli - 4.8%, and Streptococcus spp. - 3.1%. There was an increased risk of finding S. aureus, Str. uberis or Str. dysgalactiae in milk samples from chronically infected cows compared to findings in milk samples from newly infected cows. Four percent of the S. aureus isolates and 35% of the CNS isolates were resistant to penicillin G. Overall, resistance to other antimicrobials than penicillin G was uncommon.Staphylococcus aureus and CNS were the most frequently isolated pathogens and resistance to antimicrobials was rare.Mastitis is the most prevalent and most costly production disease in dairy herds worldwide [1]. The most frequently isolated micro-organisms are staphylococci, streptococci and coliforms, but other micro-organisms may infect the udder. The panorama of udder pathogens varies between countries and also between types of mastitis, e.g. clinical and subclinical.National surveys on microbial etiology of subclinical bovine
Detection of Subclinical Ketosis in Dairy Cows
Zhigang Zhang, Guowen Liu1, Hongbin Wang, Xiaobing Li1 and Zhe Wang1*
Pakistan Veterinary Journal , 2012,
Abstract: Ketosis is a common metabolic disorder frequently observed in dairy cows during the early lactation period. It is characterized by increased levels of ketone bodies in the blood, urine, and milk. Subclinical ketosis (SCK) in dairy cattle is an excess level of circulating ketone bodies in the absence of clinical signs of ketosis. Usually, detection of SCK is carried out by testing the ketone concentrations in blood, urine, and milk. Here, This review overview the detection methods for SCK in dairy cows, including cowside and laboratory tests.
Selenium and vitamin E: Reproductive disorders in dairy cows  [PDF]
Joksimovi?-Todorovi? Mirjana,Davidovi? Vesna
Veterinarski Glasnik , 2007, DOI: 10.2298/vetgl0702003j
Abstract: Selenium and vitamin E deficiency leads to reproductive disorders in dairy cows: placental retention, ovarian cysts, metritis, reduced percentage of conception, abortions, birthing of poorly vital calves. Placental retention is a post partal disorder of multifactorial etiology which has harmful effects on reproduction and the feasibility of milk production. The administration of selenium and vitamin E reduces the incidence of placental retention, which suggests that oxidative stress is responsible for the occurrence of this disorder. The occurrence of ovarian cysts has as its consequence a disorder in the oestral cycle. Vitamin E prevents oxidative damage of lipid membranes by preventing the forming of destructive hydroperoxides, acting in synergy with selenium. These nutrients protect cell membranes and lipid organelles, inhibit and destroy endogenous peroxides, and in that way protect the integrity of the membranes and reduce oxidative stress.
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.
Comparative Proteomic Studies on Serum of Brucellosis Dairy Cows and Health Dairy Cows
Jinzhong Tao,Yansheng Guo,Lihong Feng,Guoshun Zhao,Qianming Wu,Xuewen Yang,Shuxia Kuai,Shunde Liu,Jianfeng Wang
Journal of Animal and Veterinary Advances , 2012, DOI: 10.3923/javaa.2012.1864.1867
Abstract: In order to provide an evidence of brucellosis for diagnosis and prevention, 2D-electrophoresis and SDS-PAGE were applied to detect protein expression difference in plasma between healthy dairy cows and dairy cows suffered from Brucellosis. The results showed that 11 differentially protein spots were found by PDQUest 8.0 Software and 5 of them were detected by ion trap mass spectrum. Apoprotein C-III and Serum Amyloid protein A (SAA) were acute phase protein and lipometabolism-related proteins which can serves as the plasma biomarkers of brucellosis-associated proteins for diagnosis and prevention.
Profitability measures of dairy cows
Ribeiro, Anamaria Candido;McAllister, Alan Jackson;Queiroz, Sandra Aidar de;
Revista Brasileira de Zootecnia , 2008, DOI: 10.1590/S1516-35982008000900012
Abstract: this study was aimed at defining profitability measures designed for prediction of breeding values (ebv) in dairy cows. performance and economic data recorded in herds enrolled in the dhia (dairy herd improvement association) program in kentucky, usa, were used to evaluate economic functions which included the following profitability measures: lifetime net income (lni), efficiency (ef), milk income over feed costs (iofc), net income per day of productive life (nipl), net income at the end of the first lactation (ni1), and milk income over feed costs at the end of the first lactation (iofc1). the estimated averages for lni, ef, iofc, nipl, ni1 and iofc1 were respectively us$ 532.13, 1.04, us$ 3038.19, us$ -0.16, us$ -69.34 and us$ 1293.77. the heritability estimates for these traits ranged from 0.06 to 0.09. the ebv and spearman correlation estimates were positive, ranging from moderate to high values, suggesting a direct linear relationship among the profitability measures. lni was the best profitability measure and genetic correlation estimates between lni and economic measures recorded in first lactation (ni1 and iofc1) were moderate (<0.56). ni1 was the most efficient profitability measure, but it would be easier to record data to calculate iofc1. overall, results do not suggest any economic function measured in the first lactation as a selection criteria for lni. the profitability measures were affected by the short productive life of the animals in the herds. selection based on different profitability measures would not result in similar ranking of sires.
The Rising Dominance of Shigella sonnei: An Intercontinental Shift in the Etiology of Bacillary Dysentery  [PDF]
Corinne N. Thompson?,Pham Thanh Duy?,Stephen Baker
PLOS Neglected Tropical Diseases , 2015, DOI: 10.1371/journal.pntd.0003708
Abstract: Shigellosis is the major global cause of dysentery. Shigella sonnei, which has historically been more commonly isolated in developed countries, is undergoing an unprecedented expansion across industrializing regions in Asia, Latin America, and the Middle East. The precise reasons underpinning the epidemiological distribution of the various Shigella species and this global surge in S. sonnei are unclear but may be due to three major environmental pressures. First, natural passive immunization with the bacterium Plesiomonas shigelloides is hypothesized to protect populations with poor water supplies against S. sonnei. Improving the quality of drinking water supplies would, therefore, result in a reduction in P. shigelloides exposure and a subsequent reduction in environmental immunization against S. sonnei. Secondly, the ubiquitous amoeba species Acanthamoeba castellanii has been shown to phagocytize S. sonnei efficiently and symbiotically, thus allowing the bacteria access to a protected niche in which to withstand chlorination and other harsh environmental conditions in temperate countries. Finally, S. sonnei has emerged from Europe and begun to spread globally only relatively recently. A strong selective pressure from localized antimicrobial use additionally appears to have had a dramatic impact on the evolution of the S. sonnei population. We hypothesize that S. sonnei, which exhibits an exceptional ability to acquire antimicrobial resistance genes from commensal and pathogenic bacteria, has a competitive advantage over S. flexneri, particularly in areas with poorly regulated antimicrobial use. Continuing improvement in the quality of global drinking water supplies alongside the rapid development of antimicrobial resistance predicts the burden and international distribution of S. sonnei will only continue to grow. An effective vaccine against S. sonnei is overdue and may become one of our only weapons against this increasingly dominant and problematic gastrointestinal pathogen.
Postpartum Reproductive Problems and Therapy in Dairy Cows
Mehmet Can Gunduz,Ahmet Sabuncu,Melih Ucmak,Guven Kasikci,Cagatay Tek
Journal of Animal and Veterinary Advances , 2012, DOI: 10.3923/javaa.2010.1952.1954
Abstract: This study aims to establish the distribution of reproductive problems encountered during the postpartum period in dairy cows and to explore the effects of treatment procedures on reproductive performance. In the study, the ratios of assisted birth, RFM and metritis are found to be 24, 31 and 29%, respectively. Antibiogram tests performed on cows with metritis revealed that 6 cows were hypersensitive to oxytetracycline, 4 cows to enrofloxacine, 2 cows to gentamicine and 1 cow to amoxicillin. From among 45 postpartum cows used in the study, 28 (62.2%) tested positive for pregnancy. About 6 out of 11 cows giving assisted birth (54.5%), 7 out of 14 cows treated for RFM (50%) and 6 out of 13 cows (46%) treated for metritis were found to be pregnant.
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