Staphylococcus aureus is recognized for causing contagious mastitis in cattle. Elimination of the organism in affected animals is challenging due to its potential antibiotic resistance mechanisms and virulence factors. The aim of the study was the pheno- and genotypic epidemiological characterization of S. aureus isolated from bulk tank milk samples obtained from three municipalities in the northern region of Antioquia. Twenty-one S. aureus isolates from 150 bulk tank milk samples were characterized by evaluating antimicrobial susceptibility to 17 antibiotics using the VITEK 2, and identifying several genes encoding for virulence factors, enterotoxins, and the agr groups by conventional PCR. The clonal relationship between the isolates was assessed using macrorestriction fragment analysis (MRFA) of chromosomal DNA by pulsed-field gel electrophoresis (PFGE). Most of the isolates showed susceptibility to the tested antibiotics; 19% exhibited resistance to tetracycline and all isolates showed beta-lactamases. Molecular typing revealed that 76% carried the agrI and cap5 genes. Seven isolates harbored genes coding for staphylococcal enterotoxins (SE), with seh being the most identified gene. Furthermore, MRFA demonstrated high heterogeneity among the isolates, resulting in the assignment of 18 different MRFA patterns. These results indicate phenotypic resistance to tetracycline and beta-lactams, the presence of genes encoding for staphylococcal enterotoxins, and high heterogeneity among S. aureus isolates from bulk tank milk.

The objective of the study was to evaluate the frequency and genetic characteristics of ESBL-producing Escherichia coli and Klebsiella spp. and the risk factors associated with a high total bacterial count in bulk tank milk samples of dairy farms in three municipalities of the Antioquia Department, Colombia. Fifteen samples were positive for E. coli and Klebsiella spp. Subsequent analysis of the 16 S rRNA gene sequences confirmed these isolates included E. coli (n = 3), K. oxytoca (n = 11), and K. pneumoniae (n = 1). None of the isolates was positive for ESBL identification by phenotypic methods, but the only the isolate of K. pneumoniae was positive for the blaSHV61 gene by sequence analysis. The antibiotic susceptibility evaluation for all Klebsiella spp. isolates identified resistance to fosfomycin (50%; 6/12) and ampicillin (100%; 12/12). While most of the herds maintain adequate hygienic quality, specific risk factors such as having more than 60 milking cows, frequent changes in milkers, milking in paddocks, and using a chlorinated product for pre-dipping have been identified as associated with a high total bacterial count > 100,000 CFU/mL in bulk tank milk. However, certain variables including the milker being the owner of the animals and the proper washing and disinfection of the milking machine contribute to maintain a high level of hygiene and quality in the raw milk stored in the tanks. In conclusion, the frequency of ESBL producers was relatively low, with only K. pneumoniae testing positive for the blaSHV ESBL type. The presence of these bacteria in milk tanks represents a potential risk to public health for consumers of raw milk and its derivatives.

Background and Aim: Bovine mastitis is one of the most costly and prevalent diseases in dairy herds, which can be prevented and controlled through proper milking practices, diagnosis, and elimination of chronic animals, among others. Contagious pathogens such as Staphylococcus aureus and environmental pathogens such as Escherichia coli and Klebsiella spp. can affect cows and milk for human consumption, generating a public health risk. This study aimed to estimate the prevalence of herds with somatic cell count (SCC) >= 200,000 cells/mL, S. aureus, E. coli, and Klebsiella spp., in bulk tank milk (BTM) and its associated risk factors in Colombian dairy cow herds. Materials and Methods: A cross-sectional probabilistic study was carried out in 150 dairy herds located in the north of the Antioquia province. A single visit per herd was conducted, during which three BTM samples were aseptically collected. General data and milking practices were collected through an epidemiological survey applied in each herd. Results: The prevalence of S. aureus, E. coli, and Klebsiella spp. were 14% (21/150), 2% (3/150), and 8% (12/150), respectively. Moreover, 95% of the herds presented an SCC of >= 200,000 cells/mL. Practices such as in-paddock milking, change of milker during the last month, use of disposable gloves, and hand disinfection were associated with increased prevalence of S. aureus, whereas proper dipping was a protective factor. Proper washing and disinfection of the milking machine, use of chlorinated disinfectants for hand hygiene, and use of disposable gloves decreased the prevalence of E. coli and Klebsiella spp. Bulk tank SCC increased in herds with 30-60 milking cows, herds with >60 milking cows, and herds with a change of milker during the last month. Hand disinfection and dipping decreased the SCC. Conclusion: Staphylococcus aureus, E. coli, and Klebsiella spp. were prevalent in BTM from dairy cow herds. The risk of S. aureus isolation was higher in herds with an in-paddock milking system. The risk of E. coli and Klebsiella spp. isolation were higher in herds with >60 milking cows, with a change of milker during the last month. Processes such as avoiding changing the milker and greater control in medium and large herds could improve the SCC in BTM.

Background: Mastitis is the most common disease among dairy buffaloes worldwide, and it significantly affects the economic profitability of buffalo farms as well as animal welfare and public health. Methods: This study was conducted between 2018 and 2019 at the Colombian departments of Antioquia and Córdoba, where 41% of the country’s total buffalo population is concentrated. Overall, 1,018 dairy buffaloes, including 603 in Antioquia and 415 in Córdoba, distributed among 11 farms, were assessed in the study. These animals were evaluated using the California mastitis test (CMT) and somatic cell count (SCC) to determine the presence of subclinical mastitis (SM). They were considered positive for SM when the results of CMT were higher than traces and SCC was >200,000 cells/mL. Results: The total prevalence of the disease was 7.9%, and microbiological culture was performed on the samples obtained from the SM-positive animals. The main isolated bacterium was coagulase-negative Staphylococcus. Furthermore, risk factors affecting milking routine, hygiene, and farm facilities were determined. Manual milking, milking in the barn, non-disinfection of milkers' hands, etc., were identified as risk factors for the disease. Conclusion: To the best of our knowledge, this is the first large-scale study of mastitis among buffaloes in Colombia.

The present study aimed to determine Mycobacterium avium subsp. paratuberculosis (MAP) prevalence according to environmental samples and to explore the herd-level risk factors associated to MAP infection in dairy herds under mechanical milking parlor and pasture grazing-based systems. The study herds (n= 94) were located in 60 districts from five municipalities in the Northern region of the province of Antioquia, Colombia. Herds were visited once in 2016 to collect two composite environmental samples and to complete a risk assessment questionnaire. MAP identification was carried out using a quantitative real-time PCR method based on the IS900 sequence. A herd was considered as MAP-positive if one or both of the environmental samples were found positive by the molecular technique. The information on risk factors was analyzed using a multivariable logistic regression model. The apparent herd-level prevalence found was 14.9 % (14/94; 95 % CI: 7.7-22.1), ranging from 0 to 33.3 % at municipality-level. Herds where other than Pure-Holstein breeds were predominant (i.e. Jersey, Jersey crossbreeds) were more likely to be MAP-qPCR positively infected than those on which where pure-Holstein cattle was predominant (OR=3.7; 95 % CI: 1.1-15.2). The present study reports MAP prevalence in dairy herds in the province of Antioquia (Colombia), and the association between MAP environmental positivity with the predominant breed in the herd.

Objective. To determine the presence of Mycobacterium avium subsp. paratuberculosis (MAP) using serological, microbiological, and molecular methods, to genotype MAP isolates, and to explore factors associated to MAP-seropositive status in a buffalo herd of the province of Antioquia (Colombia). Materials and methods. The study was carried out to test fecal and serum samples from 21 asymptomatic adult buffaloes using culture and ELISA tests. Suspicious culture isolates were confirmed by MAP-IS900-PCR (IS900-PCR). The positive DNA was retested using MAP-IS900-quantative PCR (IS900-qPCR), and then, sub-typed using techniques based on the detection of mycobacterial interspersed repetitive units-variable number of tandem repeats (MIRU-VNTR) and multilocus short sequence repeat (MLSSR). Results. At sampling, the average age of animals was 4.7 years, 90.5% (19/21) were females and 84.2% (16/19) were pregnant. The average body condition score was 4.2 (in a 1-to-5 scale). The average milk yield was 3.5 L/day/animal. No MAP-seropositive animals were detected. One dairy buffalo cow out of the 21 buffaloes was positive by fecal culture at week 6 of incubation and then confirmed by IS900-PCR. Sub-typing analysis revealed that the MAP isolate corresponded to the INMV 3 genotype by MIRU-VNTR. Conclusions. To the best of the author’s knowledge, this is the first report of MAP diagnosis and isolation in Colombian buffaloes and the first time an INMV 3 MAP-profile is found in this species the country.

Abstract Background: Mycobacterium avium subsp. paratuberculosis (MAP) is the causative agent of paratuberculosis (PTB), an incurable enterocolitis, affecting domestic and wild ruminants. Economic losses, impacts on animal health and welfare, and public health concerns, justify its herd-level control. Aim: to systematically collect information to answer: What are the control and eradication strategies of PTB in dairy cattle worldwide? Methods: the search procedure was carried out on October 2nd, 2019 and updated on August 3rd, 2021, using OVID®, SciELO, and Redalyc databases, and the registers from the International Colloquium on Paratuberculosis (1991-2018). The inclusion criteria considered articles published in English, Portuguese, and Spanish and in peer-reviewed journals. The exclusion criteria included irrelevant topics, species other-than bovines, and not original articles. Definitive studies were obtained through consensus of the authors on eligibility and quality. Data extraction was performed, considering bibliographic information, control and outcome strategies, follow-up time, and results. Results: twenty-six relevant studies were found, reporting the use of three grouped control strategies: hygiene and management strategy (HMS), test-and-cull strategy (TCS), and vaccination strategy (VS). The HMS was the most common one (20/26), followed by TCS (17/26) and VS (7/26). Combined control strategies such as TCS-HMS (12/26), TCS-VS (1/26), and HMS-VS (1/26) were also described, and the consideration of the three control strategies (TCS-HMS-VS) was reported in two articles. The HMS included practices such as neonates/juvenile livestock hygiene, biosecurity, prevention of infection introduction into the herd, and environmental management. Within HMS, the most frequent practices were to remove calves from their dams as soon as possible after birth and to keep the minimal exposure of calves and heifers to adult cattle. As limitations, within the HMS it is considered that some strategies cannot be included due to lack of compliance, or the application of the same strategy among one study and another may have a different degree of interpretation; publication bias was not controlled since the results of the control programs in endemic countries may be not available. Conclusion: the main PTB control strategies in dairy cattle worldwide are HMS, TCS, and VS. The use of one or several combined strategies has been found to succeed in controlling the disease at herd-level.

The present study aimed to determine Mycobacterium avium subsp. paratuberculosis (MAP) prevalence according to environmental samples and to explore the herd-level risk factors associated to MAP infection in dairy herds under mechanical milking parlor and pasture grazing-based systems. The study herds (n= 94) were located in 60 districts from five municipalities in the Northern region of the province of Antioquia, Colombia. Herds were visited once in 2016 to collect two composite environmental samples and to complete a risk assessment questionnaire. MAP identification was carried out using a quantitative real-time PCR method based on the IS900 sequence. A herd was considered as MAP-positive if one or both of the environmental samples were found positive by the molecular technique. The information on risk factors was analyzed using a multivariable logistic regression model. The apparent herd-level prevalence found was 14.9 % (14/94; 95 % CI: 7.7-22.1), ranging from 0 to 33.3 % at municipality-level. Herds where other than Pure-Holstein breeds were predominant (i.e. Jersey, Jersey crossbreeds) were more likely to be MAP-qPCR positively infected than those on which where pure-Holstein cattle was predominant (OR=3.7; 95 % CI: 1.1-15.2). The present study reports MAP prevalence in dairy herds in the province of Antioquia (Colombia), and the association between MAP environmental positivity with the predominant breed in the herd.

Objetivo. Determinar la presencia de Mycobacterium avium subsp. paratuberculosis (MAP) mediante métodos serológicos, microbiológicos y moleculares, para genotipar los aislamientos de MAP y explorar factores asociados a la seropositividad a MAP en un hato de búfalos del departamento de Antioquia (Colombia). Materiales y métodos. Se realizó un estudio transversal para analizar muestras fecales y de suero de 21 búfalas adultas asintomáticas mediante cultivo y ELISA, respectivamente. Los cultivos aislados sospechosos se confirmaron mediante PCR de MAP-IS900 (IS900-PCR). El ADN positivo se volvió a analizar mediante PCR cuantitativo de MAP-IS900 (IS900-qPCR), y luego, se subtipificó utilizando unidades repetitivas intercaladas de micobacterias-número variable de repeticiones en tándem (MIRU-VNTR) y repetición de secuencia corta de múltiples locus (MLSSR). Resultados. Al muestreo, la edad promedio de los animales era de 4.7 años, el 90.5% (19/21) eran hembras y el 84.2% (16/19) estaban preñadas. El puntaje promedio de condición corporal fue 4.2 (escala de 1 a 5). La producción de leche promedio fue de 3.5 L/día/animal. No se detectaron animales seropositivos a MAP. Una hembra de los 21 búfalos fue positiva mediante cultivo fecal en la semana seis de incubación y luego se confirmó mediante IS900-PCR. El análisis de subtipado reveló que el aislado de MAP correspondía al genotipo INMV 3 por MIRU-VNTR. Conclusiones. Según el conocimiento de los autores, este es el primer diagnóstico y aislamiento de MAP en búfalos en Colombia y la primera vez que se encuentra un perfil INMV 3 de MAP en esta especie en el país.

Paratuberculosis or Johne's disease is a slow-developing infectious disease caused by Mycobacterium avium subsp. paratuberculosis (MAP) affecting mainly domestic ruminants and producing a significant economic threat to livestock production systems. Although reports on paratuberculosis in small ruminants in Colombia are very scarce, the Colombian sheep industry has identified paratuberculosis as one of the causes of its low development. There have been reports of MAP infection in sheep flocks, mainly in the Cundiboyacense Plateau and the Bogota savannah, but the prevalence of MAP infection in sheep and goat populations in Colombia is yet unknown. Therefore, the present study aimed to accurately estimate the prevalence of MAP infection at flock level in a sheep population of 24 flocks located in three regions of the province of Antioquia, Colombia. ELISA test as well as culture and direct qPCR were used as diagnostic tools. Overall, 456 blood serum samples were analysed and at least one seropositive animal was found in 17 (70% IC: 51.2-0.90) out of the 24 study flocks and, in total, 37 animals showed positive ELISA results (8% IC: 5.5-10.5). Regarding MAP direct detection, 90 faecal pools from the 24 flocks were cultured and subjected to qPCR diagnosis. Both direct qPCR and culture detected 25 (27.7%) and 64 (71.1%) faecal pools as MAP positive, respectively. More specifically, MAP positive pools were detected in 45.8% (IC: 24.3-67.3) and 83.3% (IC: 67.3-99.3) of the flocks by direct qPCR and culture, respectively. MAP infection is widespread in sheep flocks in the study regions and the combination of several diagnostic tests was necessary to achieve a more accurate and precise infection detection of this important pathogen.

Background: The increased use of body reserves observed during peripartum leads to higher needs of L-carnitine by cows, which is restrictive under the production conditions of Colombian high tropics. Objective: To evaluate the lipotropic potential of L-carnitine in Holstein dairy cows during the transition period to lactation. Methods: Twenty-one Holstein cows were fed 0, 100, or 200 g/d L-carnitine fumarate from d 260 of gestation to d 20 postpartum. Hepatic triacylglycerides concentration, total carnitine, free carnitine, acylcarnitine, and serum levels of non-esterified fatty acids (NEFA), β-hydroxybutyrate (β-HB) and urea were determined by spectrophotometry. Repeated measures analysis was used to determine the effects of dose, measurement period, and their interactions. Results: Hepatic triglycerides and the different forms of carnitine showed no difference between sampling periods (p>0.05). Hepatic triglycerides concentration was low and decreased in response to 200 g/d L-carnitine fumarate supplementation (p<0.05). This decrease in hepatic triglycerides could be due to increased fatty acid oxidation. L-carnitine supplementation significantly increased (p<0.05) blood urea concentration, possibly through stimulation of the urea cycle, as previously described in other species. Conclusion: Supplementation with L-carnitine decreased the hepatic concentration of triglycerides, possibly due to increased liver oxidation of fatty acids.

This cross-sectional study aimed to determine Mycobacterium avium subsp. paratuberculosis (MAP) herd-level prevalence using a quantitative real-time PCR method (qPCR), performed on environmental samples. Secondly, the study aimed to explore herd-level risk factors associated with the presence of MAP in dairy herds with in-paddock milking facilities of the Northern region of the Province of Antioquia (Colombia). Study herds (n = 292) located in 61 different districts from six municipalities were randomly selected amongst 7794 dairies registered in the foot-and-mouth disease vaccination records from 2015. The sampling strategy considered a proportional allocation, both at municipality and district level. Participant herds were visited once between June and October 2016 to collect one composite environmental sample and to complete a risk assessment questionnaire. Each composite environmental sample contained material from six different sites of concentration of adult cattle and/or high traffic areas (e.g. areas surrounding waterers and feeders, areas surrounding the current mobile milking-unit places). Identification of MAP was achieved using a duplex qPCR (Bactotype MAP PCR Kit®, Qiagen). A herd was considered as MAP infected if the environmental sample was positive in the qPCR. Information about the general characteristics of the herd, management practices, and knowledge about the disease was collected using the risk-assessment questionnaire. The information on risk factors was analyzed using a multivariable logistic regression model. The apparent herd-level prevalence was 4.1% (12/292; 95% CI: 1.8-6.4). Herds with a history of mixed farming of cattle with other ruminants had higher odds of being MAP infected than herds without (OR = 3.9; 95% CI: 1.2-13.2). Our study demonstrates the MAP prevalence in dairy herds from Antioquia, Colombia and the possible relationship between MAP environmental positivity with the history of mixed farming of cattle with other susceptible ruminants.

A questionnaire study was conducted among 131 veterinarians practicing in the city of Medellin, Colombia, to assess views on pain evaluation and management in dogs and cats. When pain recognition and quantification abilities were used as a perceived competence of proper pain assessment, only 83/131 (63.4%, confidence interval (CI) 0.55–0.72) were deemed to have satisfactory skills, with the rest considered to be deficient. There were 49/131 (37.4) veterinarians who had participated in continuing education programs and were more confident assessing pain, with an odds ratio (±standard error) of 2.84 ± 1.15 (p = 0.01; CI 1.27–6.32). In addition, the odds of using pain scales was 4.28 ± 2.17 (p < 0.01, CI 1.58–11.55) greater if they had also participated in continuing education programs. The term multimodal analgesia was familiar to 77 (58.7%) veterinarians who also claimed to use more than one approach to pain control. Nevertheless, homeopathy was the preferred alternative approach in 71/77 (92%). There were major misconceptions on side effects and/or contraindications for use of opioids and non-steroidal anti-inflammatory drugs (NSAIDs) by most veterinarians. In addition, the lack of multimodal analgesia by at least 40% of the practitioners, combined with heavy reliance on weak analgesics (i.e., tramadol) or those with no proven record of efficacy (homeopathic remedies), denotes major deficits in education at the undergraduate level and a need for additional continuing education designed to fulfill the gaps in knowledge identified in this study, and overcome ideological convictions not supported by scientific evidence.

Background: Equine gastric ulcer syndrome (EGUS) has been associated with duration of confinement, grain supplementation, exercise, stress, use of non-steroidal anti-inflammatory drugs, and the gastric microbiome. On the other hand, limited information is available on the risk factors for EGUS in Colombia. Objective: To determine the frequency and risk factors for the presentation of EGUS in several municipalities of Antioquia. Methods: A total of 103 male and female horses were evaluated. Endoscopic samples from different portions of the stomach were taken and subjected to histopathological analysis. Information on management conditions for each animal was also obtained. Descriptive statistics, association analysis and logistic regression were performed. Results: A69% of the animals presented at least one gastric lesion: 22.3% lesions in the squamous mucosa, 39.2% in the Margo plicatus (MP) and 48.9% in the glandular region. Diet was associated with the presentation of ulcers in the squamous mucosa (p = 0.003). MP ulceration was associated with concentrate feed consumption (p = 0.032). Conclusion: The EGUS frequency is 69%. Consumption of concentrate feed by horses in Antioquia is a critical factor for the development of ulcers in the stomach squamous and glandular regions.

There are few reports on the prevalence of gastrointestinal parasites in equines in Colombia. In this study, 946 horses were sampled from a total of 204 farms in the municipalities of Rionegro and those that comprise the Valle de Aburra, in the department of Antioquia. Fecal samples were taken directly from the rectum and processed by the McMaster, Baermann and Graham techniques. The prevalence of parasites at the farm level was 56.3% for Strongylidae, 10.7% for Strongyloides spp, 2.8% for Oxyuridae and 0.3% for Dictyocaulus spp. From a practical point of view, the most pathogenic parasites and of greatest resistance concern were the Cyathostomids, which are included within the Strongylidae and whose prevalence was greater than 50%. The OR of presenting Strongylidae was 49% lower in equines that participated in fairs compared to those that did not. The OR of presenting Strongylidae was 56% lower in equines that use stables than those not being stalled. Also, the OR of being positive to Oxyuris equi was 88% lower in animals that participate in fairs compared to those that did not, and was 3.66 times higher in equines with body condition ≤ 2 in comparison with those of body condition ≥3. Based on this information, it is important to initiate studies that evaluate the state of antihelminthic resistance and the relationship between parasitic load and clinical condition in order to determine the real impact of these parasites on the equines of these regions.

There are few reports on the prevalence of gastrointestinal parasites inequines in Colombia. In this study, 946 horses were sampled from a totalof 204 farms in the municipalities of Rionegro and those that comprisethe Valle de Aburrá, in the department of Antioquia. Fecal samples weretaken directly from the rectum and processed by the McMaster, Baermannand Graham techniques. The prevalence of parasites at the farm level was56.3% for Strongylidae, 10.7% for Strongyloides spp, 2.8% for Oxyuridae and0.3% for Dictyocaulus spp. From a practical point of view, the most pathogenicparasites and of greatest resistance concern were the Cyathostomids,which are included within the Strongylidae and whose prevalence was greaterthan 50%. The OR of presenting Strongylidae was 49% lower in equinesthat participated in fairs compared to those that did not. The OR of presentingStrongylidae was 56% lower in equines that use stables than those notbeing stalled. Also, the OR of being positive to Oxyuris equi was 88% lowerin animals that participate in fairs compared to those that did not, and was3.66 times higher in equines with body condition ≤ 2 in comparison withthose of body condition ≥3. Based on this information, it is important toinitiate studies that evaluate the state of antihelminthic resistance and therelationship between parasitic load and clinical condition in order to determinethe real impact of these parasites on the equines of these regions.

Esta investigación, se llevó a cabo, debido a la poca información nacional existente en hemoparásitos equinos y su objetivo fue determinar la prevalencia de babesiosis y tripanosomiasis, en el Valle de Aburrá y Rionegro, municipios de Antioquia (Colombia), así como algunos factores de riesgo asociados a la presentación de seropositividad, a estas enfermedades. En 223 predios, con una población de 1.008 equinos, se tomó muestra de sangre venosa, para realizar el diagnóstico serológico y molecular. La información epidemiológica fue obtenida, a través de la aplicación de una encuesta dirigida a las personas a cargo de los animales. Para el análisis estadístico, se aplicó Chi cuadrado de independencia y la Prueba Exacta de Fisher, cuando fue necesario. Para las asociaciones bivariadas, se calcularon estimaciones del riesgo (OR) por variable explicativa, con sus respectivos intervalos de confianza, del 95% (I.C. 95%). Se encontró una prevalencia del 11,9%, para babesiosis y de 1,9%, para tripanosomiasis; como factor de protección, se encontró el hecho de salir a una feria. Para la piroplasmosis, el lugar geográfico, el sexo, estar castrado, ser positivos a Anemia Infecciosa Equina (AIE), estrongílidos u oxiurus fueron factores de riesgo. Para tripanosomiasis, el factor de riesgo fue estar infestado con Dermacentor nitens o ser mular. Se deben reforzar métodos de vigilancia epidemiológica activa, sobre todo, en casos de movilización continua de equinos o desarrollo de eventos, que involucren presencia masiva de ejemplares.

Background: Leptospirosis in cattle is recognized as a major cause of reproductive loses due to abortions, early embryonic death, and infertility. The type of Leptospira serovars that are currently circulating in Colombian herds is largely unknown due to the lack of national reports. Objective: The prevalence of antibodies specific to 13 Leptospira spp serovars was investigated in unvaccinated cows from 26 herds in San Pedro de los Milagros (Province of Antioquia) dairy region. Methods: Microscopic agglutination test was used on serum samples, following WHO recommendations. Results: A total of 112/900 (12.4%) of the animals had antibody titers of 1:100 or greater to at least one Leptospira serovar. Of those positive, 34/900 (3,8%) animals seroconverted to two or more serovars. In order of decreasing prevalence, the serovars detected were: hardjo prajitno, pomona, grippotyphosa, tarassovi, copenhageni, canicola, cellodeni and bratislava. There were 28 animals seropositive to serovar hardjo. Conclusion: Our results indicate that leptospirosis should be included as a differential diagnosis for various reproductive problems in this region.

Background: Johne´s disease (JD) is a severe enteritis that affects ruminants and has been diagnosed in cattle and sheep in Colombia. However, epidemiological information on the disease in this country is scarce. Objective: to identify factors associated with the JD serum enzyme-linked immunosorbent assay (ELISA) status of dairy cows. Methods: a cross-sectional study was carried out in 307 asymptomatic adult Holstein dairy cows from 14 herds in nine districts of Belmira and San Pedro de los Milagros municipalities during November, 2007. Nineteen to 29 cows, ≥ 2 years of age were randomly selected and blood sampled from every herd. A commercial ELISA kit was used to analyze sera. Information regarding cow related factors (age, farm-born, parity, and daily milk yield) and herd management practices (i.e. herd size, herd average milk production, current presence of symptomatic animals, cattle purchase, own animals grazing in foreign pastures, feeding of calves before weaning, manure spread on pastures, and sighting of birds in feed storing areas) was collected using questionnaires. Descriptive statistics were computed for all variables and a multivariable logistic regression model was constructed (p<0.05). Results: ten percent (31/307; 95% CI: 7-14%) of the animals were positive by ELISA. In 70% (10/14) of the herds, ELISA detected at least one positive animal. Cow and herd factors such as “parity” and “feeding of calves before weaning” showed weak and strong associations with ELISA positive results, respectively. The odds ratio (OR) for JD seropositivity increased 20% (OR = 1.20; 95% CI: 0.98-1.47; p = 0.067) in cows with > 1 parity. The OR was 0.74 times lower (OR = 0.26; 95% CI: 0.096-0.70; p<0.01) in herds feeding calves with pooled colostrum from several cows, compared to herds feeding calves with colostrum from their own dams. Conclusion: JD seroprevalence was 10 and 70% at animal and herd-level, respectively. Cow and herd factors “parity” and “feeding of calves before weaning” showed weak and strong association with positive results, respectively.

Introducción: la mastitis se define como la inflamación de la glándula mamaria causante de grandes pérdidas económicas en hatos lecheros, lo que amerita su investigación. Objetivo: determinar la tasa de incidencia de mastitis clínica TIMC, la etiología asociada y la sensibilidad antibiótica de patógenos aislados de casos de mastitis en ganado lechero. Materiales y métodos: se siguieron 37 hatos por 12 meses para el diagnóstico de mastitis cílínica (MC). A las muestras de leche de los casos de MC se les realizó cultivo bacteriológico y a estas, así como a los aislamientos de casos de mastitis subclínica de un estudio previo, se les efectuó prueba de susceptibilidad antibiótica. Para el análisis de la información se utilizó estadística descriptiva estándar. Resultados: TIMC fue de 13,8 casos por 100 vacas-año a riesgo. Se aislaron 188 patógenos totales de casos de MC, entre los cuales el Streptococcus agalactiae, el Streptococcus pyogenes y el Corynebacterium spp. fueron los más frecuentes, con 29,8; 11,7 y 5,9 %, respectivamente. Se halló una alta sensibilidad de las bacterias contagiosas para los antibióticos cloxacilina y cefoperazone. Conclusiones: en el presente estudio se encontró una TIMC de 13,8 casos por 100 vacasaño a riesgo. Los patógenos más prevalentes identificados en casos de MC fueron contagiosos. Se encontró una alta sensibilidad de las bacterias contagiosas para la mayoría de los antibióticos β-lactámicos.