Molecular Epidemiology and Phyloevolutionary Analysis of Porcine Parvoviruses (PPV1 through PPV7) Detected in Replacement Gilts from Colombia.

Eight porcine parvovirus (PPV) species, designated as PPV1 through PPV8, have been identified in swine. Despite their similarities, knowledge about their distribution and genetic differences remains limited, resulting in a gap in the genetic classification of these viruses. In this study, we conducted a comprehensive analysis using PPV1 to PPV7 genome sequences from Colombia and others available in the GenBank database to propose a classification scheme for all PPVs. Sera from 234 gilts aged 180 to 200 days were collected from 40 herds in Colombia. Individual detection of each PPV (PPV1 through PPV7) was performed using end-point PCR. Complete nucleotide (nt) sequencing was performed on the PPV1 viral protein (VP), and near-complete genome (NCG) sequencing was carried out for novel porcine parvoviruses (nPPVs) (PPV2 through PPV7). Phylogenetic analyses were conducted by comparing PPV1-VP sequences to 94 available sequences and nPPVs with 565 NCG, 846 nPPV-VP, and 667 nPPV-nonstructural protein (NS) sequences. Bayesian phylogenetic analysis was used to estimate substitution rates and the time to the most recent common ancestor for each PPV. The highest prevalence was detected for PPV3 (40.1%), followed by PPV5 (20.5%), PPV6 (17%), PPV1 (14.5%), PPV2 (9.8%), PPV4 (4.2%), and PPV7 (1.3%). Notably, all tested sera were negative for PPV8 genomes. An analysis of the PPV1-VP sequences revealed two main clades (PPV1-I and PPV1-II), with the sequences recovered in this study grouped in the PPV1-II clade. Comparative analysis showed significant genetic distances for PPV2 to PPV7 at the NCG (>6.5%), NS (>6.3%), and VP (>7.5%) regions, particularly when compared to equivalent regions of PPV genomes recovered worldwide. This study highlights the endemic circulation of nPPVs in Colombian pig herds, specifically among gilts. Additionally, it contributes to the phylogenetic classification and evolutionary studies of these viruses. The proposed method aims to categorize and divide subtypes based on current knowledge and the genomes available in databanks.

EFFECTS OF BEEF SEMEN AND BEEF EMBRYO STRATEGIES ON PROFITABILITY: Economics of using beef semen and beef in vitro produced embryo transfer in Jersey herds.

Dairy herds have adopted sexed semen (SS) and beef semen (BS) to control heifer inventory and increase calf sales revenue. Beef in vitro-produced embryo transfer (beef IVP-ET) may be an alternative to increase calf sales revenue. Besides, raising those Jersey beef crossbred and/or pure beef animals in a dairy system may be a new source of revenue. We aimed to evaluate breed strategies combining dairy conventional semen (CS), SS, BS, and beef IVP-ET on herd dynamics and profitability by marketing those animals with one-day-old or raising them to 180 kg. A Markov chain model was developed to maximize the profitability of Jersey herds by changing the number of dairy heifers sold at birth and the culling rate of 3rd and greater parity cows. The model presents inputs on the reproductive and productive performance of heifers and cows over time. The last year's data (year 10 - steady state) was used to calculate accrual operational cost and revenue per cow per year. We varied the breeding strategy by breeding order and parities, the embryo transfer cost ($85 or $170), the pure beef calf market price ($200 or $300), and by marketing Jersey-beef and pure beef animals with one-day-old or raising them to 180 kg. A total of 8 scenarios + default scenario were simulated. Overall, the proportion of SS use was 47.3 ± 0.6%. For the scenarios replacing all CS breedings with BS breedings, the proportion of CS and BS used was 52.3 ± 0.6. When beef IVP-ET was used, the percentage of BS and beef IVP-ET used was 22.4 ± 0.1% and 31.0 ± 0.1%, respectively. We observed that when we compared SS:BS with the default scenario, the production of purebred Jersey male calves was reduced by 83.5%, and profit/cow per year was increased from $113.5 to $203.3 with SS:BS. When a beef IVP-ET of $85 per transfer was used (scenarios 2 and 3), profit/cow per year was $145.5 and $176.2 for a pure-beef calf price of $200 and $300, respectively. In scenario 4, with a beef IVP-ET cost of $170, the lowest profit ($52.9 per cow per year) was found when marketing one-day-old pure-beef calves at $200. The highest profit was achieved for scenario raising the Jersey-beef crossbred animals to 180 kg ($232.9, scenario 6), followed by scenario 7 ($222.9, SS:BS:IVP-ET) with an embryo transfer cost of $85. Under the current market conditions, combining SS and BS in the reproductive program was a feasible economic opportunity for Jersey herds, yielding the highest net return. The adoption of beef IVP-ET in a reproductive program can potentially increase profit/cow per year, but its profitability will depend on the beef IVP-ET pregnancy cost, the pure-beef market price, calf performance, and the herd reproductive performance. In conclusion, raising the Jersey-beef crossbred calves may be a profitable strategy, and dairy producers need to evaluate the best option to invest in since it will take an extra risk to produce high-quality animals to the market.

Phylogenetic analysis of the partial sequences of the env and tax BLV genes reveals the presence of genotypes 1 and 3 in dairy herds of Antioquia, Colombia.

Bovine leukemia virus (BLV) is a retrovirus that primarily infects dairy cows. Although few studies have also used the tax gene, phylogenetic studies of BLV use mostly the env gene. The aim of this work was to establish the circulating genotypes of BLV in specialized dairy cattle from Antioquia, Colombia. Twenty blood samples from Holstein Friesian cows were collected, and their DNA was isolated. A PCR was performed for a partial region of the env and tax genes. A phylogenetic analysis was carried out using the maximum likelihood and Bayesian methods for both genes. Nineteen sequences were identified as genotype 1 by env and tax genes. Only one sequence was clustered with genotype 3 and had the highest proportion of different nucleotide sites compared to other strains. Four amino acid substitutions in the 134 amino acid residue fragment of the Env protein were identified in the Colombian sequences, and three new amino acid substitutions were reported in the 296 amino acid residue fragment of the Tax protein. R43K (Z finger), A185T (Activation domain), and L105F changes were identified in the genotype 3 sample. This genotype has been reported in the United States, Japan, Korea, and Mexico, but so far, not in Colombia. The country has a high rate of imported live animals, semen, and embryos, especially from the United States. Although it is necessary to evaluate samples from other regions of the country, the current results indicate the presence of two BLV genotypes in specialized dairy herds.

Bovine leukosis virus, bovine viral diarrhea, and bovine neosporosis seroprevalence in specialized dairy herds in Antioquia-Colombia.

Enzootic bovine leukosis (EBL) is a chronic infectious disease caused by the bovine leukosis virus (BLV), a Deltaretrovirus. Bovine viral diarrhea (BVD) is an infectious disease caused by a pestivirus. Bovine neosporosis is caused by the obligate intracellular parasite Neospora caninum (Nc). These pathogens can have horizontal (postnatal) or vertical (transplacental) transmissions and affect the productive and reproductive performance of infected bovines. This work aimed to detect BLV, BVD, and Nc seroprevalence in specialized dairy cattle from the north, east, and Aburrá Valley regions of the Department of Antioquia, the highest in milk production regions in Antioquia. A total of 599 blood samples, obtained from 53 specialized dairy cattle herds, were evaluated by the ELISA test. The results revealed a seroprevalence of 41.13% for BLV (242/599), 28.48% (163/599) for Nc, and 22.7% (132/599) for BVD. Regarding the regional seroprevalence evaluation, BLV was found in 47.02% of the samples from the east, 36.87% from the north, and 46.02% from the Aburrá Valley. Nc was found in 31.03% of the samples from the east, 24.26% from the north, and 36.63% from Aburrá Valley. BVD was found in 21.62% of the samples from the east, 25.03% from the north region, and 10.39% of the samples from the Aburrá Valley. It is highlighted by these results that the north region, with the highest milk production in Antioquia, had the lowest BLV and Nc seroprevalences but the highest seroprevalence of BVD. BLV has increased in Antioquia in recent years, and as an immunosuppressive infection, opportunities for other pathogens are created by it. A significant statistical difference was found in the average prevalence of the pathogens according to the municipality, cattle breed, and region of origin of the sample. The seroprevalence of these pathogens in specialized dairy herds in Antioquia can be classified as medium-low. However, it is recommended that biosecurity practices should be maximized to avoid the spread of these pathogens due to the variability detected in the region, municipality, breed group, and herd age. The rapid and efficient diagnosis of these three pathogens through reliable methodologies will allow for the control of dissemination in dairy herds.

Clinico-pathological and immunohistochemical findings in a case of bovine cutaneous angiomatosis in a Holstein heifer / Achados clínico-patológicos e imuno-histoquímicos em um caso de angiomatose cutânea bovina em uma novilha Holandesa

ABSTRACT: Bovine cutaneous angiomatosis (BCA) is a rare condition characterized by vasoproliferative skin lesions mainly affecting cattle in the northern hemisphere. An eight-month-old Holstein heifer showed two skin easy-bleeding nodules bulging from the epidermis in the forehead and close to the right prescapular region. Skin lesions were within the dermis and had an irregular surface and a soft heterogeneous reddish parenchyma composed of numerous variable-sized arterioles, veins, and capillaries surrounded by abundant collagenous fibrous tissue. Immunohistochemical assays evidenced endothelial cells lining proliferative vascular structure immunolabeled for CD31 and Von Willebrand factor, and vascular smooth muscle cells immunostained for smooth muscle actin. All clinical, pathological, and immunohistochemical features observed in the Holstein heifer were hallmarks of BCA. Considering its potential for hereditary spread, BCA must be included in the differential diagnosis of easily bleeding skin nodules that do not respond to routine topical wound treatments to prevent its spread in Brazilian herds.

RESUMO: A angiomatose cutânea bovina (ACB) é uma condição rara caracterizada por lesões vasoproliferativas na pele que afetam principalmente bovinos do hemisfério norte. Uma novilha Holandesa de oito meses de idade apresentou dois nódulos cutâneos protuberantes na epiderme, que apresentavam fácil sangramento localizados na fronte e próximo à região pré-escapular direita. As lesões cutâneas dérmicas tinham uma superfície irregular e um parênquima avermelhado heterogêneo macio composto por numerosas arteríolas, veias e capilares de tamanho variável circundadas por tecido fibroso colagenoso abundante. O exame imuno-histoquímico evidenciou células endoteliais revestindo a estrutura vascular proliferativa imunomarcadas para CD31 e fator de Von Willebrand, e células vasculares de músculo liso imunomarcadas para actina de músculo liso. Todas as características clínicas, patológicas e imuno-histoquímicas observadas na novilha Holandesa foram características da ACB. Considerando seu potencial de disseminação hereditária, a ACB deve ser incluída no diagnóstico diferencial dos nódulos cutâneos de fácil sangramento que não respondem aos tratamentos tópicos de rotina para evitar sua disseminação nos rebanhos brasileiros.

Clinico-pathological and immunohistochemical findings in a case of bovine cutaneous angiomatosis in a Holstein heifer / Achados clínico-patológicos e imuno-histoquímicos em um caso de angiomatose cutânea bovina em uma novilha Holandesa

Bovine cutaneous angiomatosis (BCA) is a rare condition characterized by vasoproliferative skin lesions mainly affecting cattle in the northern hemisphere. An eight-month-old Holstein heifer showed two skin easy-bleeding nodules bulging from the epidermis in the forehead and close to the right prescapular region. Skin lesions were within the dermis and had an irregular surface and a soft heterogeneous reddish parenchyma composed of numerous variable-sized arterioles, veins, and capillaries surrounded by abundant collagenous fibrous tissue. Immunohistochemical assays evidenced endothelial cells lining proliferative vascular structure immunolabeled for CD31 and Von Willebrand factor, and vascular smooth muscle cells immunostained for smooth muscle actin. All clinical, pathological, and immunohistochemical features observed in the Holstein heifer were hallmarks of BCA. Considering its potential for hereditary spread, BCA must be included in the differential diagnosis of easily bleeding skin nodules that do not respond to routine topical wound treatments to prevent its spread in Brazilian herds.

A angiomatose cutânea bovina (ACB) é uma condição rara caracterizada por lesões vasoproliferativas na pele que afetam principalmente bovinos do hemisfério norte. Uma novilha Holandesa de oito meses de idade apresentou dois nódulos cutâneos protuberantes na epiderme, que apresentavam fácil sangramento localizados na fronte e próximo à região pré-escapular direita. As lesões cutâneas dérmicas tinham uma superfície irregular e um parênquima avermelhado heterogêneo macio composto por numerosas arteríolas, veias e capilares de tamanho variável circundadas por tecido fibroso colagenoso abundante. O exame imuno-histoquímico evidenciou células endoteliais revestindo a estrutura vascular proliferativa imunomarcadas para CD31 e fator de Von Willebrand, e células vasculares de músculo liso imunomarcadas para actina de músculo liso. Todas as características clínicas, patológicas e imuno-histoquímicas observadas na novilha Holandesa foram características da ACB. Considerando seu potencial de disseminação hereditária, a ACB deve ser incluída no diagnóstico diferencial dos nódulos cutâneos de fácil sangramento que não respondem aos tratamentos tópicos de rotina para evitar sua disseminação nos rebanhos brasileiros.

Bovine Viral Diarrhea Virus within and herd prevalence on pasture-based dairy systems, in southern Chile dairy farms.

Bovine Viral Diarrhea (BVD) is a ubiquitous endemic disease in most bovine populations that causes a negative economic impact on cattle production systems. However, true herd and individual prevalence in Chile have not been estimated based on statistical and epidemiological considerations and uncertainty regarding the infection's extension at animal and herd levels. In addition, the risk factors that can influence how the infection has spread among the cattle premises have not been assessed yet. Therefore, the study aimed to estimate true herd and animal prevalence of active BVDV infection in pasture-based dairy herds and to evaluate risk factors potentially associated with the status of herds and the within-herd prevalence, using a Bayesian approach. A cross-sectional study was performed over a random stratified (proportional to herd size) sample of one-hundred and fifty dairy herds selected in Chile's two leading dairy regions (Region de Los Ríos and Region de Los Lagos). We obtained 12.311 blood samples from lactating cows, but 4.998 randomly selected samples were processed due to budget constraints. For estimating BVDV Herd Prevalence (HP), a herd was considered infected if at least one positive animal to Ag-ELISA was found. In addition, a survey was completed on each farm, aiming to collect information to assess the influence of some variables over the state of the herds; both estimations were obtained using a Bayesian approach. True herd prevalence and true individual prevalence of BVDV active infection were estimated at 77 % and 3.5 % respectively, no significant differences were found between characteristics like herd size, location, vaccination, etc. Open herds and herds that mix herd categories are more likely to have higher BVDV prevalence.

Sp Tripanosomiasis en el ganado: breve revisión de la literatura / En Trypanosomiasis in cattle: brief literature review / Tripanossomose em bovinos: breve revisão de literatura

Teniendo uno de los rebaños comerciales de ganado más grandes del mundo, Brasil se destaca entre otros países, sin embargo, entre los problemas sanitarios que afectan a estos rebaños, la tripanosomosis ha ido ganando espacio y gran trascendencia, debido a los grandes problemas económicos y reproductivos que son que viene provocando en el rebaño brasileño. El agente causal más importante es Trypanosoma vivax, que son protozoos diseminados a través de vectores mecánicos, como tábanos y moscas hematófagas como las del género Stomoxys. Estos agentes se distribuyen por todo el mundo, pero preferentemente en las zonas de clima tropical de Brasil, afectando tanto al ganado lechero como al vacuno, causando grandes daños a los ganaderos. Los signos clínicos de esta enfermedad son inespecíficos, lo que ha suscitado preocupación por la diseminación y falta de diagnóstico de esta enfermedad, pero principalmente incluyen anemia o pérdida progresiva de peso, además de pérdida de productividad en los animales afectados. El diagnóstico se realiza mediante pruebas parasitológicas, como frotis de sangre, pruebas serológicas y moleculares y, principalmente, mediante el método Woo. Finalmente, el tratamiento y control de esta enfermedad consiste en tratamientos de quimioterapia y control de los vectores causantes. En este sentido, esta breve revisión de la literatura tiene como objetivo levantar d

Having one of the largest commercial herds of cattle in the world, Brazil stands out among other countries, however, among the sanitary problems that affect these herds, Trypanosomosis has been gaining space and great significance, due to the major economic and reproductive problems that are coming causing in the brazilian herd. The most important and causative agent is Trypanosoma vivax, which are protozoa disseminated by mechanical vectors, such as horseflies and hematophagous flies such as those of the genus Stomoxys. These agents are distributed all over the world, but preferentially in tropical climate areas in Brazil, affecting both dairy and beef cattle, causing great damage to farmers. The clinical signs of this disease are nonspecific, which has raised concern about the spread and lack of diagnosis of this disease, but mainly include anemia or progressive weight loss, in addition to loss of productivity in affected animals. Diagnosis is made through parasitological tests, such as blood smears, serological and molecular tests, and, mainly, using the Woo method. Finally, the treatment and control of this disease consists of chemotherapy treatments and control of the causative vectors. In this sense, this brief literature review aims to raise data on this disease, such as: etiological agent, clinical signs, epidemiology, diagnosis and treatment, in order to contribute wit

Ao possuir um dos maiores rebanhos comerciais de bovinos do mundo, o Brasil destaca-se entre os demais países, entretanto, dentre os problemas sanitários que acometem esses rebanhos a tripanossomose vem ganhando espaço e grande significância, devido aos grandes problemas econômicos e reprodutivos que vem causando no rebanho brasileiro. O agente de maior importância e causador é o Trypanossoma vivax, que são protozoários disseminados por meio de vetores mecânicos, como tabanídeos e moscas hematófagas como as do gênero Stomoxys. Esses agentes estão distribuídos por todo o mundo, mas preferencialmente em áreas de clima tropicais no Brasil, acometendo tanto bovinos leiteiros quanto bovinos de corte, causando grandes prejuízos aos criadores. Os sinais clínicos desta doença são inespecíficos, o que tem gerado preocupação pela disseminação e falta de diagnóstico dessa enfermidade, mas incluem, principalmente, anemia ou perda progressiva de peso, além de perda da produtividade dos animais acometidos. O diagnóstico é feito por meio de exames parasitológicos, como esfregaços sanguíneos, exames sorológicos e molecular e, principalmente, pelo método de Woo. Por fim o tratamento e controle dessa doença consiste em tratamentos quimioterápicos e controle dos vetores causadores. Neste sentido, esta breve revisão de literatura tem por objetivo levantar dados sobre tal doença, como: agente etiol

Tripanosomíase no rebanho bovino brasileiro ­ Uma breve revisão da literatura / Trypanosomiasis in cattle - Brief literature review / Tripanosomiasis en el ganado - Breve revisión de la literatura

Ao possuir um dos maiores rebanhos comerciais de bovinos do mundo, o Brasil destaca-se entre os demais países, entretanto, dentre os problemas sanitários que acometem esses rebanhos a tripanossomose vem ganhando espaço e grande significância, devido aos grandes problemas econômicos e reprodutivos que vem causando no rebanho brasileiro. O agente de maior importância e causador é o Trypanossoma vivax, que são protozoários disseminados por meio de vetores mecânicos, como tabanídeos e moscas hematófagas como as do gênero Stomoxys. Esses agentes estão distribuídos por todo o mundo, mas preferencialmente em áreas de clima tropicais no Brasil, acometendo tanto bovinos leiteiros quanto bovinos de corte, causando grandes prejuízos aos criadores. Os sinais clínicos desta doença são inespecíficos, o que tem gerado preocupação pela disseminação e falta de diagnóstico dessa enfermidade, mas incluem, principalmente, anemia ou perda progressiva de peso, além de perda da produtividade dos animais acometidos. O diagnóstico é feito por meio de exames parasitológicos, como esfregaços sanguíneos, exames sorológicos e molecular e, principalmente, pelo método de Woo. Por fim o tratamento e controle dessa doença consiste em tratamentos quimioterápicos e controle dos vetores causadores. Neste sentido, esta breve revisão de literatura tem por objetivo levantar dados sobre tal doença, como: agente etiológico, sinais clínicos, epidemiologia, diagnóstico e tratamento, a fim de contribuir com informações sobre a enfermidade que está ganhando espaço e necessita de maior disseminação de conhecimentos, para que não seja esquecida e subdiagnosticada.(AU)

Having one of the largest commercial herds of cattle in the world, Brazil stands out among other countries, however, among the sanitary problems that affect these herds, Trypanosomosis has been gaining space and great significance, due to the major economic and reproductive problems that are coming causing in the brazilian herd. The most important and causative agent is Trypanosoma vivax, which are protozoa disseminated by mechanical vectors, such as horseflies and hematophagous flies such as those of the genus Stomoxys. These agents are distributed all over the world, but preferentially in tropical climate areas in Brazil, affecting both dairy and beef cattle, causing great damage to farmers. The clinical signs of this disease are nonspecific, which has raised concern about the spread and lack of diagnosis of this disease, but mainly include anemia or progressive weight loss, in addition to loss of productivity in affected animals. Diagnosis is made through parasitological tests, such as blood smears, serological and molecular tests, and, mainly, using the Woo method. Finally, the treatment and control of this disease consists of chemotherapy treatments and control of the causative vectors. In this sense, this brief literature review aims to raise data on this disease, such as: etiological agent, clinical signs, epidemiology, diagnosis and treatment, in order to contribute with information about the disease that is gaining ground and needs further dissemination of knowledge, so that it is not forgotten and underdiagnosed.(AU)

Teniendo uno de los rebaños comerciales de ganado más grandes del mundo, Brasil se destaca entre otros países, sin embargo, entre los problemas sanitarios que afectan a estos rebaños, la tripanosomosis ha ido ganando espacio y gran trascendencia, debido a los grandes problemas económicos y reproductivos que son que viene provocando en el rebaño brasileño. El agente causal más importante es Trypanosoma vivax, que son protozoos diseminados a través de vectores mecánicos, como tábanos y moscas hematófagas como las del género Stomoxys. Estos agentes se distribuyen por todo el mundo, pero preferentemente en las zonas de clima tropical de Brasil, afectando tanto al ganado lechero como al vacuno, causando grandes daños a los ganaderos. Los signos clínicos de esta enfermedad son inespecíficos, lo que ha suscitado preocupación por la diseminación y falta de diagnóstico de esta enfermedad, pero principalmente incluyen anemia o pérdida progresiva de peso, además de pérdida de productividad en los animales afectados. El diagnóstico se realiza mediante pruebas parasitológicas, como frotis de sangre, pruebas serológicas y moleculares y, principalmente, mediante el método Woo. Finalmente, el tratamiento y control de esta enfermedad consiste en tratamientos de quimioterapia y control de los vectores causantes. En este sentido, esta breve revisión de la literatura tiene como objetivo levantar datos sobre esta enfermedad, tales como: agente etiológico, signos clínicos, epidemiología, diagnóstico y tratamiento, con el fin de aportar información sobre la enfermedad que está ganando terreno y necesita una mayor difusión del conocimiento. para que no sea olvidado e infradiagnosticado.(AU)

Leptospirosis in dairy cattle from southern Brazil - risk factors

Background: Cattle are susceptible to chronic leptospirosis infection, that results in reduced milk production and reproductive disorders such as abortions, stillbirths, fetal malformation, and mummified fetuses, causing significant economic losses.Commercially available vaccines against leptospirosis offer limited protection to cattle because they contain only the mostprevalent serovars worldwide, even though they are not prevalent in the specific region. This study aimed to evaluate theprevalence of specific antibodies against Leptospira serogroups, reproductive disorders and the risk factors in dairy herdsfrom different mesoregions of Rio Grande do Sul State, Southern Brazil.Materials, Methods & Results: An epidemiological survey was conducted, and serum samples from the bovine population representative of three mesoregions (MR1, MR2, and MR3) were studied; the samples were collected and tested forleptospirosis using the microscopic agglutination test (MAT) for 12 serogroups checking for the presence of agglutination.A total of 442 blood samples were collected from dairy cattle from November to December 2019 (MR1, 187; MR2, 88;and MR3, 167), including cows vaccinated with different commercial vaccines during the three months before sample collection (n = 295) and non-vaccinated against leptospirosis (n = 147). At the time of collection, an interview was conductedwith the owners with questions about the health of the animals, management, habitat, feeding and reproduction. Chi-squaretests univariate analysis with the SPSS® version 20.0 were performed to estimate the association of serogroup Djasimanseroreactivity with the occurrence of reproductive problems and related risk factors. The mean prevalence of antibodiesagainst leptospires was 78.7% (MR1, 74.9 %; MR2, 84.1 %; and MR3, 80.2 %). Serogroup prevalence was different in...

Pathogenic Leptospira spp. Seroprevalence and Herd-Level Risk Factors Associated with Chilean Dairy Cattle.

Leptospirosis is a ubiquitous distributed zoonotic infectious disease present in wild and domestic animals. This study aimed to estimate within-herd and herd-level seroprevalence against pathogenic Leptospira spp. in dairy cows from southern Chile and identify risk factors associated with the herd-level status. We used a multi-stage strategy combined with a stratified sample strategy for randomly sampling 147 herds and 4876 lactating cows. We considered as infected a herd with at least one positive reactor to MAT. In addition, an epidemiological survey was applied to the herd's owners and a logistic regression (LR) model was constructed to analyze it. The overall within-herd prevalence was 5.9% (95% CI 4.9-6.8), the overall herd-level prevalence was 42.2% (95% CI 9.2-47.9), and there was variation in both between different herd sizes. L. borgpetersenii serovars Hardjo and Tarassovi and L. interrogans serovar Pomona were the more frequent serovars in non-vaccinated herds. A factor that decreases the risk of a farm being infected was Leptospira vaccine usage (OR = 0.04; 95% CI = 0.02-0.11), and variables that increase risk were using bulls for mating (OR = 3.43; 95% CI = 1.1-10.1) and continuous calving distribution (OR = 3.4; 95% CI = 1.3-8.8). The study's results will contribute to unravelling the infection burden in the main dairy area of the country and designing control strategies.

Conocimientos, actitudes, prácticas y percepción de riesgo de los trabajadores de hatos lecheros de la Colonia 07 Montes frente a las zoonosis específicas / Knowledge, attitudes, practices and perception of risk of dairy herd workers in Colonia 07 Montes regarding specific zoonoses

Los trabajadores de hatos lecheros están en constante riesgo de contraer enfermedades zoonóticas como la brucelosis, tuberculosis, leptospirosis y carbunco bacteridiano, por la exposición a agentes biológicos y el contacto directo con animales durante el desarrollo de sus labores. Se describe el nivel de conocimientos, actitudes, prácticas, percepción de riesgo y las características sociodemográficas de los trabajadores de hatos lecheros de la colonia 07 Montes del distrito de Curuguaty, frente a las zoonosis, en el último trimestre del 2019. Fue un estudio cuantitativo, observacional, descriptivo, de corte transversal en el cual se utilizó un cuestionario con 33 preguntas aplicado a 121 trabajadores, con el que se recogieron variables demográficas, conocimientos, actitudes, prácticas y percepción de riesgo. Los datos se analizaron a través del programa estadístico SPSS. Para el análisis univariado, se empleó la estadística descriptiva para representar los datos expresados en frecuencias, porcentajes y tablas. El 52,9 % de los trabajadores tenía conocimiento sobre la brucelosis, tuberculosis y leptospirosis, el 74,4 % tenía actitudes positivas, el 66,9% implementaba prácticas positivas y el 52,9% percibía el riesgo. Menos del 75% de los trabajadores encuestados tenían conocimientos, actitudes, prácticas y percepciones de riesgo óptimos, lo que resulta preocupante considerando la exposición constante de los mismos a las enfermedades zoonóticas, es por ello que se deberían implementar estrategias educativas de carácter multisectorial concernientes a estas patologías y sus medidas preventivas a modo de mejorar esta situación

Dairy herd workers are at constant risk of contracting zoonotic diseases such as brucellosis, tuberculosis, leptospirosis and anthrax, due to exposure to biological agents and direct contact with animals during the performance of their work. The level of knowledge, attitudes, practices, risk perception and sociodemographic characteristics of dairy herd workers in the 07 Montes colony of the Curuguaty district against zoonosis was described in the last trimester of 2019. A quantitative, observational study, descriptive, cross-sectional, in which a questionnaire with 33 questions applied to 121 workers was used, with which demographic variables, knowledge, attitudes, practices and risk perception were collected. The data were analyzed through the SPSS statistical program. For the univariate analysis, descriptive statistics were used to represent the data expressed in frequencies, percentages and tables. It was observed that 52.9% of the workers had knowledge about zoonotic diseases, 74.4% had positive attitudes, 66.9% implemented positive practices and 52.9% perceived the risk. Less than 75% of the workers surveyed had optimal knowledge, attitudes, practices and perceptions of risk, which is worrying considering their constant exposure to zoonotic diseases, that is why multisectoral educational strategies should be implemented concerning these pathologies and their preventive measures to improve this situation

Detection of Pestivirus A (bovine viral diarrhea virus 1) in free-living wild boars in Brazil.

Bovine viral diarrhea virus (BVDV) is a major pathogen in cattle herds. Considering the epidemiological importance of pestiviruses and the process of wild boar invasion in Brazil, this study aimed to investigate the presence of BVDV in free-living boars. Forty-nine free-living wild boars were collected by exotic wildlife controller agents in 2017 and 2018. The presence of BVDV antibodies was evaluated in 42 serum samples using the virus neutralization test, and the detection of BVDV RNA was performed from the 5'UTR genomic region by RT-PCR assay in 49 lung tissue samples followed by sequencing of amplicons. BVDV neutralizing antibodies in serum were not identified in any of the evaluated samples. However, 3/49 (6.12%) lung samples were positive for BVDV RNA and classified one as BVDV-1a and two as 1d subgenotype. This report identified BVDV RNA in free-living wild boars and these results should be considered in BVDV control programs, especially in extensive beef cattle rearing systems.

Prevalence of bovines persistently infected with bovine viral diarrhea virus (BVDV) in dairy cattle herds in Paraná State, Brazil / Prevalência de bovinos persistentemente infectados com o vírus da diarreia viral bovina (BVDV) em rebanhos leiteiros no estado do Paraná, Brasil

This study aimed to establish the prevalence of animals persistently infected (PI) with bovine viral diarrhea virus (BVDV) in dairy farms at Parana State, Brazil. Samples were collected from 6,465 female Holstein Friesian Dairy Cattle, including animals less than two years old, females over two years old who had not given birth at the farm, and mothers of calves diagnosed as persistently infected. The cattle came from 40 dairy herds distributed in 10 municipalities in the State of Paraná. The samples were obtained from May 2015 to August 2018. The diagnosis of PI animals was made with an antigen-capture ELISA test. We detected PI animals in fifteen herds sampled (37.5%), ranging from one to sixteen animals per herd. The prevalence in Parana State's municipalities was 1.78%, ranging from 0.3 to 8.9% at positive herds. The analysis of the individual herds shows significant dissemination of the BVDV in Parana's municipalities, including endemic areas. With this, we highlight the need for measures to raise awareness among producers about the existence and importance of bovine viral diarrhea (BVD) in dairy herds, reinforcing the PI animals' role in disease epidemiology and the economic impact caused by the maintenance of these farm animals.(AU)

Com o intuito de se estabelecer a prevalência de animais persistentemente infectados (PI) com o BVDV em propriedades leiteiras no estado do Paraná. Foram coletadas amostras de 6.465 bovinos, fêmeas, da raça Holandês Preto e Branco (HPB). Amostraram-se animais com idade inferior a dois anos, fêmeas com mais de dois anos que não haviam tido partos na propriedade, e mães de bezerros que foram diagnosticados como persistentemente infectados. Os bovinos foram provenientes de 40 rebanhos leiteiros, distribuídos em 10 municípios no Estado do Paraná. A coleta deu-se no período de maio de 2015 a agosto de 2018. O diagnóstico dos animais PI foi feito por meio do teste de ELISA de captura de antígeno. Animais PI foram detectados em quinze rebanhos amostrais (37,5%), oscilando entre um e dezesseis animais por rebanho. A prevalência nos municípios do estado Paraná foi de 1,78%, oscilando entre 0,3 a 8,9% nos rebanhos positivos. Com a alta prevalência de animais PI observada, quando analisados os rebanhos amostrais individualmente, é possível afirmar que há uma disseminação importante do BVDV em municípios paranaenses, destacando inclusive áreas endêmicas. Com isso, vê-se a necessidade de medidas de conscientização dos produtores sobre a existência e importância da BVD nos rebanhos, destacando o papel dos animais PI na epidemiologia da doença, bem como o impacto econômico causado pela manutenção desses animais nos rebanhos.(AU)

Prevalence of bovines persistently infected with bovine viral diarrhea virus (BVDV) in dairy cattle herds in Paraná State, Brazil

ABSTRACT: This study aimed to establish the prevalence of animals persistently infected (PI) with bovine viral diarrhea virus (BVDV) in dairy farms at Parana State, Brazil. Samples were collected from 6,465 female Holstein Friesian Dairy Cattle, including animals less than two years old, females over two years old who had not given birth at the farm, and mothers of calves diagnosed as persistently infected. The cattle came from 40 dairy herds distributed in 10 municipalities in the State of Paraná. The samples were obtained from May 2015 to August 2018. The diagnosis of PI animals was made with an antigen-capture ELISA test. We detected PI animals in fifteen herds sampled (37.5%), ranging from one to sixteen animals per herd. The prevalence in Parana States municipalities was 1.78%, ranging from 0.3 to 8.9% at positive herds. The analysis of the individual herds shows significant dissemination of the BVDV in Paranas municipalities, including endemic areas. With this, we highlight the need for measures to raise awareness among producers about the existence and importance of bovine viral diarrhea (BVD) in dairy herds, reinforcing the PI animals role in disease epidemiology and the economic impact caused by the maintenance of these farm animals.

RESUMO: Com o intuito de se estabelecer a prevalência de animais persistentemente infectados (PI) com o BVDV em propriedades leiteiras no estado do Paraná. Foram coletadas amostras de 6.465 bovinos, fêmeas, da raça Holandês Preto e Branco (HPB). Amostraram-se animais com idade inferior a dois anos, fêmeas com mais de dois anos que não haviam tido partos na propriedade, e mães de bezerros que foram diagnosticados como persistentemente infectados. Os bovinos foram provenientes de 40 rebanhos leiteiros, distribuídos em 10 municípios no Estado do Paraná. A coleta deu-se no período de maio de 2015 a agosto de 2018. O diagnóstico dos animais PI foi feito por meio do teste de ELISA de captura de antígeno. Animais PI foram detectados em quinze rebanhos amostrais (37,5%), oscilando entre um e dezesseis animais por rebanho. A prevalência nos municípios do estado Paraná foi de 1,78%, oscilando entre 0,3 a 8,9% nos rebanhos positivos. Com a alta prevalência de animais PI observada, quando analisados os rebanhos amostrais individualmente, é possível afirmar que há uma disseminação importante do BVDV em municípios paranaenses, destacando inclusive áreas endêmicas. Com isso, vê-se a necessidade de medidas de conscientização dos produtores sobre a existência e importância da BVD nos rebanhos, destacando o papel dos animais PI na epidemiologia da doença, bem como o impacto econômico causado pela manutenção desses animais nos rebanhos.

Prevalence of bovines persistently infected with bovine viral diarrhea virus (BVDV) in dairy cattle herds in Paraná State, Brazil / Prevalência de bovinos persistentemente infectados com o vírus da diarreia viral bovina (BVDV) em rebanhos leiteiros no estado do Paraná, Brasil

This study aimed to establish the prevalence of animals persistently infected (PI) with bovine viral diarrhea virus (BVDV) in dairy farms at Parana State, Brazil. Samples were collected from 6,465 female Holstein Friesian Dairy Cattle, including animals less than two years old, females over two years old who had not given birth at the farm, and mothers of calves diagnosed as persistently infected. The cattle came from 40 dairy herds distributed in 10 municipalities in the State of Paraná. The samples were obtained from May 2015 to August 2018. The diagnosis of PI animals was made with an antigen-capture ELISA test. We detected PI animals in fifteen herds sampled (37.5%), ranging from one to sixteen animals per herd. The prevalence in Parana State's municipalities was 1.78%, ranging from 0.3 to 8.9% at positive herds. The analysis of the individual herds shows significant dissemination of the BVDV in Parana's municipalities, including endemic areas. With this, we highlight the need for measures to raise awareness among producers about the existence and importance of bovine viral diarrhea (BVD) in dairy herds, reinforcing the PI animals' role in disease epidemiology and the economic impact caused by the maintenance of these farm animals.(AU)

Com o intuito de se estabelecer a prevalência de animais persistentemente infectados (PI) com o BVDV em propriedades leiteiras no estado do Paraná. Foram coletadas amostras de 6.465 bovinos, fêmeas, da raça Holandês Preto e Branco (HPB). Amostraram-se animais com idade inferior a dois anos, fêmeas com mais de dois anos que não haviam tido partos na propriedade, e mães de bezerros que foram diagnosticados como persistentemente infectados. Os bovinos foram provenientes de 40 rebanhos leiteiros, distribuídos em 10 municípios no Estado do Paraná. A coleta deu-se no período de maio de 2015 a agosto de 2018. O diagnóstico dos animais PI foi feito por meio do teste de ELISA de captura de antígeno. Animais PI foram detectados em quinze rebanhos amostrais (37,5%), oscilando entre um e dezesseis animais por rebanho. A prevalência nos municípios do estado Paraná foi de 1,78%, oscilando entre 0,3 a 8,9% nos rebanhos positivos. Com a alta prevalência de animais PI observada, quando analisados os rebanhos amostrais individualmente, é possível afirmar que há uma disseminação importante do BVDV em municípios paranaenses, destacando inclusive áreas endêmicas. Com isso, vê-se a necessidade de medidas de conscientização dos produtores sobre a existência e importância da BVD nos rebanhos, destacando o papel dos animais PI na epidemiologia da doença, bem como o impacto econômico causado pela manutenção desses animais nos rebanhos.(AU)

Parity and season affect hematological, biochemical, and milk parameters during the early postpartum period in grazing dairy cows from high-tropics herds.

Improving the early detection of animals or herds at increased risk for diseases, reduced milk yield or impaired reproductive performance should be an essential component of herd health programs. The present study aimed to describe the findings of hematological, biochemical, and milk analytes of grazing cows from tropical dairy herds during the early postpartum period, and the effects of parity and calving season. In the North of Antioquia, Colombia which is the major area of specialized dairy production in the country, a longitudinal study comprising 260 dairy cows selected at calving, was conducted. Blood and milk sampling were made to establish red blood cell count, white blood cell count, minerals, protein traits and, milk composition. Variables were checked for normal distribution. The Box-Cox transformation was used when necessary. Variables were statistically analyzed using a GLM model considering parity and calving season as fixed effects. Using a parametric or non-parametric method based on the distribution of the variables, single average values, and 90% confidence intervals were determined considering fixed effects founds in the GLM model. Blood values affected by parity in lactating dairy cows grazing in highland tropical herds included serum calcium levels, red blood cell counts, hematocrit, hemoglobin, mean corpuscular hemoglobin, and total eosinophil counts, whereas blood values affected by season included: total leukocyte counts, total and differential lymphocyte counts, serum albumin and globulin concentration, and serum albumin:globulin ratio (P < 0.05). Data from our study could be used for comparison studies between lactating dairy cows within tropical herds or between tropical and seasonal dairy herds.

Evaluation of two strategies for reducing the spread of Salmonella in commercial swine herds during the finishing phase and their incremental cost-effectiveness ratios / Avaliação de duas estratégias para redução da infecção por Salmonella em rebanhos comerciais de suínos na fase de terminação e a razão incremental de custo efetividade

To achieve control of Salmonella contamination in pig carcasses, on-farm measures need to be better understood. Complementary strategies require research not only on their effectiveness but also on their financial impact. In this study, we evaluated the incremental cost-effectiveness ratio of two treatments for reducing Salmonella seroprevalence in commercial swine herds. Pigs treated with a prebiotic or a vaccine were studied and compared with pigs in an untreated control group. Each strategy was applied to three batches of pigs in a commercial integration system; the animals were followed from farrowing to the slaughterhouse, and their serologies upon arrival at finishing farms and before slaughter were evaluated. Additionally, carcass surface contamination was assessed for each strategy. The seroprevalence upon arrival at the finishing farm was lower than 3% in all groups. In the control and vaccine groups, the seroprevalence increased by more than 90 percentage points from the day of arrival at the finishing farm to four days before slaughter. Only the prebiotic treatment yielded a significant effect on preslaughter seroprevalence (a 49 percentage points reduction from that in the control). Carcass contamination was 0% in the prebiotic group, 18.33% in the control group and 29.16% in the vaccine group. Only prebiotics significantly reduced the seroprevalence of Salmonella in the studied herds, and the incremental cost-effectiveness ratio associated with prebiotic use was 1.92 USD to reduce seroprevalence by 10 percentage points per carcass ton.(AU)

Para alcançar controle da contaminação por Salmonella em carcaças suínas, intervenções na produção primária precisam ser melhor compreendidas. Estratégias complementares requerem não só pesquisas acerca da sua efetividade, mas também dos custos implicados no uso de tais tecnologias. Para tanto, foi avaliada a razão de custo-efetividade incremental de dois tratamentos para reduzir a soroprevalência de Salmonella em rebanhos suínos comerciais. O uso de um prebiótico e de uma vacina foram comparados com um controle sem tratamento. Cada estratégia foi aplicada em três lotes de suínos em um sistema comercial de integração. Os animais foram acompanhados da maternidade até o abate e suas sorologias no dia do alojamento na terminação e quatro dias antes do abate foram avaliadas. Também, em cada estratégia, amostras de suabe de carcaça foram coletadas para avaliação da contaminação superficial. A soroprevalência no dia do alojamento na terminação foi menor do que 3% em todos os grupos, sendo que nos grupos controle e vacina a soroprevalência aumentou mais de 90 pontos percentuais quatro dias antes do abate. Apenas o uso do prebiótico levou a um efeito significativo na redução da soroprevalência pré-abate (49 pontos percentuais), quando comparado com o controle. A contaminação das carcaças no grupo prebiótico foi 0%, 18,33% no controle e 29,16 no grupo vacinado. Assim, apenas o prebiótico foi capaz de reduzir a soroprevalência nos rebanhos estudados com razão incremental de custo-efetividade de 1,92 USD para redução de 10 pontos percentuais na soroprevalência por tonelada de carcaça.(AU)

Evaluation of two strategies for reducing the spread of Salmonella in commercial swine herds during the finishing phase and their incremental cost-effectiveness ratios / Avaliação de duas estratégias para redução da infecção por Salmonella em rebanhos comerciais de suínos na fase de terminação e a razão incremental de custo efetividade

To achieve control of Salmonella contamination in pig carcasses, on-farm measures need to be better understood. Complementary strategies require research not only on their effectiveness but also on their financial impact. In this study, we evaluated the incremental cost-effectiveness ratio of two treatments for reducing Salmonella seroprevalence in commercial swine herds. Pigs treated with a prebiotic or a vaccine were studied and compared with pigs in an untreated control group. Each strategy was applied to three batches of pigs in a commercial integration system; the animals were followed from farrowing to the slaughterhouse, and their serologies upon arrival at finishing farms and before slaughter were evaluated. Additionally, carcass surface contamination was assessed for each strategy. The seroprevalence upon arrival at the finishing farm was lower than 3% in all groups. In the control and vaccine groups, the seroprevalence increased by more than 90 percentage points from the day of arrival at the finishing farm to four days before slaughter. Only the prebiotic treatment yielded a significant effect on preslaughter seroprevalence (a 49 percentage points reduction from that in the control). Carcass contamination was 0% in the prebiotic group, 18.33% in the control group and 29.16% in the vaccine group. Only prebiotics significantly reduced the seroprevalence of Salmonella in the studied herds, and the incremental cost-effectiveness ratio associated with prebiotic use was 1.92 USD to reduce seroprevalence by 10 percentage points per carcass ton.

Para alcançar controle da contaminação por Salmonella em carcaças suínas, intervenções na produção primária precisam ser melhor compreendidas. Estratégias complementares requerem não só pesquisas acerca da sua efetividade, mas também dos custos implicados no uso de tais tecnologias. Para tanto, foi avaliada a razão de custo-efetividade incremental de dois tratamentos para reduzir a soroprevalência de Salmonella em rebanhos suínos comerciais. O uso de um prebiótico e de uma vacina foram comparados com um controle sem tratamento. Cada estratégia foi aplicada em três lotes de suínos em um sistema comercial de integração. Os animais foram acompanhados da maternidade até o abate e suas sorologias no dia do alojamento na terminação e quatro dias antes do abate foram avaliadas. Também, em cada estratégia, amostras de suabe de carcaça foram coletadas para avaliação da contaminação superficial. A soroprevalência no dia do alojamento na terminação foi menor do que 3% em todos os grupos, sendo que nos grupos controle e vacina a soroprevalência aumentou mais de 90 pontos percentuais quatro dias antes do abate. Apenas o uso do prebiótico levou a um efeito significativo na redução da soroprevalência pré-abate (49 pontos percentuais), quando comparado com o controle. A contaminação das carcaças no grupo prebiótico foi 0%, 18,33% no controle e 29,16 no grupo vacinado. Assim, apenas o prebiótico foi capaz de reduzir a soroprevalência nos rebanhos estudados com razão incremental de custo-efetividade de 1,92 USD para redução de 10 pontos percentuais na soroprevalência por tonelada de carcaça.

Risk factors for high bulk milk somatic cell counts in dairy herds from Campos das Vertentes region, Minas Gerais State, Brazil: a case-control study / Fatores de risco para contagens elevadas de células somáticas no leite de tanque em rebanhos de bovinos da região de Campos das Vertentes, Minas Gerais, Brasil: um estudo de caso-controle

High bulk milk somatic cell counts (BMSCC) are indicative of failures related to the control of mastitis in the herd, which compromises the quality of the milk and generates great losses for the producers and for the industry. A case-control study was carried out in dairy herds in the Campos das Vertentes region, Minas Gerais State, Brazil, in order to contribute to the knowledge of the risk factors involved with elevated BMSCC. The study involved 46 dairy herds, of which 30 were considered cases (BMSCC ≥700,000 cells/mL of milk) and 16 control farms (BMSCC ≤200,000 cells/mL of milk). Sixteen qualitative variables and four quantitative variables were analyzed. The results showed that the risk factors for BMSCC ≥700,000 cells/mL were the presence of Staphylococcus aureus and Streptococcus agalactiae pathogens in bulk milk, non-use of pre and post-dipping, non-use of disposable paper towel for drying of mammary glands, non-monitoring of mastitis in the herd by means of California Mastitis Test (CMT) or individual somatic cell counts (SCC), non-implementation of the milking line and therapy of dry cows and failures in hygiene of teats and udders before milking. Moderate correlations were also observed between the elevation of BMSCC and counts of S. aureus and BMSCC and counts S. agalactiae in bulk milk, and a moderate correlation between S. aureus and S. agalactiae counts in bulk milk. Failures with regard to the maintenance and use of milking equipment, including manual pressure application in milking assemblies, unregulated milking vacuum pressure, and vacuum loss during milking, and maintenance failures of the milking machine and bulk milk tank were also pointed out as important risk factors of BMSCC elevation. The results of this study provided subsidies for the elaboration of more effective programs for mastitis control and improvement of raw milk quality, reducing the losses caused by the disease to producers and industry.(AU)

Altas contagens de células somáticas no leite do tanque (CCSt) são indicativas de falhas relacionadas com o controle da mastite no rebanho, o que compromete a qualidade do leite e gera grandes perdas para os produtores e para a indústria. Visando identificar os fatores de risco envolvidos com a CCSt elevada, foi realizado um estudo de caso-controle em rebanhos bovinos leiteiros da região de Campos das Vertentes, em Minas Gerais. O estudo envolveu 46 propriedades, das quais 30 foram consideradas casos (CCSt ≥700.000 cels/mL de leite) e 16 propriedades controles (CCSt ≤200.000 cels/mL de leite). Foram analisadas 16 variáveis qualitativas e quatro variáveis quantitativas. Os resultados demonstraram que os fatores de risco para valores de CCSt ≥700.000 cels/mL de leite foram a presença dos patógenos Staphylococcus aureus e Streptococcus agalactiae, não utilização do pré e de pós-dipping, não utilização de papel toalha descartável para a secagem dos tetos, não monitoramento da mastite por meio do California Mastitis Test (CMT) ou CCS individual, não implementação da linha de ordenha e da terapia de vacas secas e falhas na higiene de tetos e de úbere antes da ordenha. Também se observaram correlações moderadas entre a CCSt e as contagens de S. aureus e entre CCSt e as contagens de S. agalactiae, e correlação moderada entre as contagens de S. aureus e de S. agalactiae no leite do tanque. Falhas com relação à manutenção e utilização dos equipamentos de ordenha, aplicação de pressão manual nos conjuntos da ordenha, pressão de vácuo da ordenha desregulada, perda de vácuo durante a ordenha e falhas de manutenção da ordenhadeira e do tanque de expansão foram também apontadas como fatores de risco para elevação da CCSt. Os resultados deste estudo possibilitaram identificar fatores de risco importantes para contagens elevadas de CCSt que poderão fornecer subsídios para a elaboração de programas de controle mais efetivos para a mastite e para a melhoria da qualidade do leite, mitigando o impacto que a doença causa para os produtores e para a indústria.(AU)