Association of paratuberculosis sero-status with milk production and somatic cell counts across 5 lactations, using multilevel mixed models, in dairy cows.

The aim of this work was to investigate associations between individual cow Mycobacterium avium ssp. paratuberculosis (MAP) seropositivity, 305-d corrected milk production, and somatic cell count during 5 lactations lifespan in Portuguese dairy herds using multilevel mixed models. We used MAP serum ELISA (Idexx MAP Ac, Idexx Laboratories Inc., Westbrook, ME) results (n = 23,960) from all the 20,221 adult cows present in 329 farms and corresponding 47,586 lactation records from the National Dairy Improvement Association. Cows and farms were classified as positive or negative. Multilevel mixed models were used to investigate the association of cow MAP status with variation in milk production and somatic cell count. Cow MAP status, farm status, and lactation number were considered as independent variables. A quadratic function of lactation number was used to mimic the effect of lactation order on milk production. The models considered 3 levels: measurement occasion (level 1) within cow (level 2) and cow within farm (level 3). Four final models were produced, including all herds and cows, to address the effect of farm status (models 1 and 2) or the effect of cow status (models 3 and 4) on the outcome variables. Our results show that MAP status affects milk production. Losses are detectable from third lactation onward. During the first 5 lactations, positive cows accumulated an average loss of 1,284.8 kg of milk when compared with the negative cows. We also observed that somatic cell counts were higher in positive cows and a positive interaction occurs between cow status and lactation number, suggesting a positive association between MAP infection and increased somatic cell counts. Our results are in line with previous studies, suggesting a possible positive relation between cow milk production and susceptibility to MAP infection.

Antimicrobial resistance in companion animals - Veterinarians' attitudes and prescription drivers in Portugal.

Antimicrobial resistance transmitted from companion animals is a threat to public health increased by the pet's relationship with humans. This study aims to understand the attitude and drivers of antimicrobial (AM) prescription among companion animal veterinarians in Portugal and identify actions to combat antimicrobial resistance (AMR). This cross-sectional study is based on a questionnaire with 417 respondents representing the Portuguese veterinary population. The results allowed grouping the respondents according to the attitude of prescription. Two types of veterinarians were identified: those who prefer to prescribe treatments based on the animals' signs and their own experience - empirical-oriented type - and those who refer to a guidance protocol to assist the prescription decision - protocol-oriented type. Respondents working in hospitals displayed a positive association with the use of guidance protocols. Efficacy was the main driver of prescription for both groups, suggesting that no matter the attitude in prescribing, the veterinarian's aim is achieving positive clinical results. Most respondents prefer empirical-oriented prescriptions, declare the absence of protocols for the prudent use of AM at the workplace and do not refer to AMR issues nor the need for hygiene reinforcement measures with owners. Owners are less likely to request AMs from veterinarians aged over 43 years old. It was discovered that communication between owners and veterinarians about risks associated with AMR was poor and must be improved and the adoption of a national guideline for the adequate use of AM directed for companion animals would be beneficial.

Incidence, characteristics and geographical distributions of canine and human non-Hodgkin's lymphoma in the Porto region (North West Portugal).

Lymphoma is one of the most common neoplasms in dogs and it is one of the top five causes of cancer-related deaths, similar to human lymphoma. Companion animal epidemiological studies define dogs as sentinels of potential risk factors for human health, mainly due to shared environments, shorter disease latencies, and spontaneous disease. The aims of this study were to describe human and canine epidemiologic features of non-Hodgkin's lymphoma (NHL) and their similarities, and to investigate a possible geographical association in the incidence risks in the Greater Porto area, in north-western Portugal. The postal codes of human NHL patients diagnosed between 2005 and 2010 residing in the Greater Porto, Portugal, were obtained from North and Central Region Cancer Registries of Portugal. Available data from dogs diagnosed with lymphoma between 2005 and 2016 from several veterinary centres were also collected. Descriptive epidemiology, mapping cases, and age-standardised risks of NHL incidence (ASR) were determined for both species. The results showed a higher risk (P<0.05) of NHL in men (ASR men: 18.1 cases/100,000 inhabitants; women: 14.2 cases/100,000 inhabitants) and in male dogs (ASR males: 82 cases/100,000 dogs; females: 70 cases/100,000 dogs). The geographical distribution of human and canine ASR was well correlated (r=0.664, P<0.05), with the highest values for human and canine ASR detected in the same urban municipalities of the Greater Porto: Porto, Matosinhos and Maia. These findings suggest the existence of exposure similarities, supporting the relevance of cancer surveillance in pet animals as efficient tools to predict health hazards for humans.

Immunocytochemical study of canine lymphomas and its correlation with exposure to tobacco smoke.

AIM: Canine lymphoma is one of the most common canine neoplasms, but little is known regarding the effects of exposure to tobacco smoke on their biologic behavior. As cytology is the most frequent diagnostic method of canine lymphoma, the aims of this study were to perform an immunocytochemical study of canine lymphomas, including subtyping and cell proliferation analysis, and to establish their correlation with tobacco smoke exposure. MATERIALS AND METHODS: A total of 23 dogs diagnosed with lymphoma were subjected to careful fine-needle biopsies of enlarged lymph nodes. The smears were air-dried, fixed with cold acetone, and immunocytochemically stained using CD3, PAX5, and Ki-67. Owners were requested to complete an epidemiologic questionnaire. RESULTS: According to the updated Kiel classification, 65% were B-cell lymphomas - three low grade (LG) and 12 high grade (HG) and 35% were T-cell -two LG and six HG. Thirteen tumors presented high Ki67 indexes (>40%) (11 HG and 2 LG), two revealed moderate ones (20-40%) (1 HG and 1 LG), and three had low indexes (≤20%) (1 HG and 2 LG). Both a significant positive correlation and a significant linear-by-linear association (p=0.018) were observed between high Ki67 indexes and smoking owners (r=0.753, p=0.002) as well as with the number of smokers in the household (r=0.641, p=0.001). Moreover, the mean percentage of Ki67+ cells from the group of "smoker owners" was statically higher (p=0.011) than that from the "non-smoker owners." CONCLUSION: The results suggest that cytological diagnosis of canine lymphomas benefits from being complemented with immunocytochemical studies that include subtyping and assessment of proliferative activity, both contributing for the prognosis and therapeutic planning. Furthermore, exposure to tobacco smoke seems to be related to the biological behavior of canine lymphomas.

Estimated BVDV-prevalence, -contact and -vaccine use in dairy herds in Northern Portugal.

A study to evaluate BVDV-prevalence, recent -contact and -vaccine use in dairy herds in the "Entre Douro e Minho" (EDM) region in North Portugal was carried out in 124 dairy herds in 2003. Herds were visited to ascertain BVDV-vaccine use and to collect a bulk tank milk (BTM) sample and serum from 1268 cattle to analyse BVDV-antibodies using an NS2-3 ELISA. Fifty-three percent of farmers used inactivated BVDV-vaccines whilst the remaining farmers were not presently using BVDV-vaccines. BMT-antibody results included 35% positives, 25% negative and 39% inconclusive, and were similar in vaccinated and non-vaccinated herds (p>0.05) and allowed estimating a 10% BVDV herd-prevalence from prior knowledge of the relationship between BMT-antibody results and probability of PI cattle in the herd. Overall individual seroprevalence was 27% and was 23% in non-vaccinated and 36% in vaccinated cattle (p<0.05). Contact of the herd with BVDV was assessed according to seroprevalence in young and adult cattle in the herd and it was estimated that 35% of herds were infected or had recent contact with BVDV, 40% were not infected and did not have recent contact with BVDV and the BVDV-infection and -contact status of remaining herds was undetermined. The results from this study indicate BVDV is endemic and BVDV-vaccines are widespread in the dairy-cattle population in EDM region in Portugal.

Prevalence of antimicrobial resistance in faecal enterococci from vet-visiting pets and assessment of risk factors.

The objective of this study was to determine the prevalence of antimicrobial resistance (AMR) exhibited by enterococci isolated from faeces of pets and its underlying risk factors. From September 2009 to May 2012, rectal swabs were collected from 74 dogs and 17 cats, selected from the population of animals visiting the Veterinary Hospital of University of Porto, UPVet, through a systematic random procedure. Animal owners answered a questionnaire about the risk factors that could influence the presence of AMR in faecal enterococci. Enterococci isolation, identification and antimicrobial (AM) susceptibility testing were performed. Data analyses of multilevel, univariable and multivariable generalised linear mixed models were conducted. From all enterococci isolated (n=315), 61 per cent were considered multidrug-resistant, whereas only 9.2 per cent were susceptible to all AMs tested. Highest resistance was found to tetracycline (67.0 per cent), rifampicin (60.3 per cent), azithromycin (58.4 per cent), quinupristin/dalfopristin (54.0 per cent) and erythromycin (53.0 per cent). Previous fluoroquinolone treatments and coprophagic habits were the features more consistently associated with the presence of AMR for three (chloramphenicol, ciprofloxacin and azithromycin) and seven (tetracycline, rifampicin, gentamicin, chloramphenicol, ciprofloxacin, erythromycin and azithromycin), respectively, out of nine AMs assessed. Evaluating risk factors that determine the presence of drug-resistant bacteria in pets, a possible source of resistance determinants to human beings, is crucial for the selection of appropriate treatment guidelines by veterinary practitioners.

Risk factors for Salmonella spp in Portuguese breeding pigs using a multilevel analysis.

Salmonella is the second most frequent cause of foodborne illness in the European Union (EU), so EU enforced legislation to achieve a reduction in Salmonella prevalence in the swine sector. To set the reduction target each country carried out a baseline survey to estimate Salmonella prevalence. The aim of our study was to identify risk factors for the presence of Salmonella in breeding pigs based on the data of the Baseline Study for Salmonella in Breeding Pigs in Portugal. In total, 1670 pen fecal samples from 167 herds were tested by culture and 170 samples tested positive. Along with the collection of the samples a survey was applied to collect information about the herd management and potential risk factors. Multilevel analysis was applied to the data using generalized linear mixed models and a logit link function. The outcome variable was the presence/absence of Salmonella in the pen fecal samples. The first level was assigned to the pen fecal samples and the second level to the herds. The results showed significant associations between Salmonella occurrence and the factors (p<0.05): maternity pens versus mating pens (OR=0.39, 95%CI: 0.24-0.63), feed from external or mixed source versus home source (OR=2.81, 95%CI: 1.19-6.61), more than 10 animals per pen versus 10 animals per pen (OR=2.02, 95%CI: 1.19-3.43), North Region versus Alentejo Region (OR=3.86, 95%CI: 1.08-13.75), rodents control (OR=0.23, 95%CI: 0.090-0.59), more than 90% of boars homebred or no boars versus more than 90% of boars from an external source (OR=0.54, 95%CI: 0.3-0.97), semen from another herd versus semen from insemination centers (OR=4.47, 95%CI: 1.38-14.43) and herds with a size of 170 or more sows (OR=1.82, 95%CI: 1.04-3.19). This study offers very relevant information for both the Portuguese veterinary authorities and the pig farmers currently developing control programmes for Salmonella. This is the first study providing evidence for semen and boars source as risk factors for Salmonella in breeding pigs.

Relationship between zoometric measurements in Holstein-Friesian cow and cubicle size in dairy farms / Relación entre medidas zoométricas en vacas Holstein-Friesian y dimensiones de cubículos en granjas lecheras

Body measurements in Portuguese Holstein-Friesian breed and its association with the dimensions of the cubicles were investigated. During a period of 5 months, body measurements and cubicles size data from 55 commercial Portuguese dairy herds were collected including in total 1054 individual cows. Data were analyzed using the general linear model and principal components. The most relevant body measurements were: height at withers (141.1±4.72 cm), height at rump (144.2±4.47 cm), length of trunk (170.8±8.31 cm), width of biiliac (55.9±4.17 cm) and perimeter of the thorax (206.8±10.43 cm). In general, the first class of parity showed significant different measures (P<0.001) associated with the development of animals. Head to head cubicle length and cubicle width were 223.0±11.0 cm and 113.0±5.0 cm respectively; whereas in cubicle against wall length was 227.0±18.0 cm and width 111.0±7.0 cm. The highest correlations were found for body measures between the different heights and between the height at chest and perimeter of the thorax. The analysis showed no relation between body measurements and dimensions of the cubicles. Principal component analysis of the different body measurements and cubicles dimensions expressed 51.4% of the total variability, in which the first factor represented 40.2% and the second factor 11.1%.

Fueron investigadas las medidas corporales en la raza Holstein-Friesian Portuguesa y su asociación con las dimensiones de los cubículos. Durante un período de 5 meses, se recogieron las medidas corporales y los datos de tamaño de cubículos de 55 explotaciones lecheras comerciales portuguesas incluyendo un total de 1054 animales. Los datos fueron analizados utilizando el modelo linear general y componentes principales. Las medidas del cuerpo más relevantes fueron: altura a la cruz (141,1±4,7 cm), altura a la grupa (144,2±4,5 cm), longitud del tronco (170,8±8,3 cm), ancho biisquiática (55,9±4,2 cm) y el perímetro del tórax (206,8±10,4 cm). En general, la primera paridad reveló diferencias (P<0,001), lo que se encuentra asociado con el desarrollo de los animales. La longitud y la ancho del cubículo cabeza con cabeza fue 223±11 cm y 113±5 cm respectivamente, mientras que en el cubículo frente a la pared, la longitud fue 227±18 cm y el ancho de 111±7 cm. Las medidas del cuerpo con las más altas correlaciones se observaron entre las diferentes alturas y entre la altura del pecho y el perímetro del tórax. El análisis no evidenció relación alguna entre las medidas del cuerpo y las dimensiones de los cubículos. El análisis de componentes principales de las medidas del cuerpo y de las diferentes dimensiones de los cubículos explican el 51,4% de la variabilidad total, en la que el primer factor representa el 40,2% y el segundo el 11,1%.

Capability index--a statistical process control tool to aid in udder health control in dairy herds.

Bulk milk somatic cell count (BMSCC) averages have been used to evaluate udder health both at the individual or the herd level as well as milk quality and hygiene. The authors show that the BMSCC average is not the best tool to be used in udder health control programs and that it can be replaced with advantage by the capability index (Cpk). The Cpk is a statistical process control tool traditionally used by engineers to validate, monitor, and predict the expected behavior of processes or machines. The BMSCC data of 13 consecutive months of production from 414 dairy herds as well as SCC from all cows in the DHI program from 264 herds in the same period were collected. The Cpk and the annual BMSCC average (AAVG) of all the herds were calculated. Confronting the herd's performance explained by the Cpk and AAVG with the European Union (EU) official limit for BMSCC of 400,000 cells/mL, it was noticed that the Cpk accurately classified the compliance of the 414 farms, whereas the AAVG misclassified 166 (40%) of the 414 selected farms. The annual prevalence of subclinical mastitis (SMP) of each herd was calculated with individual SCC data from the same 13-mo period. Cows with more than 200,000 SCC/mL were considered as having subclinical mastitis. A logistic regression model to relate the Cpk and the herd's subclinical mastitis prevalence was calculated. The model is: SMPe = 0.475 e(-0.5286 x Cpk). The validation of the model was carried out evaluating the relation between the observed SMP and the predicted SMPe, in terms of the linear correlation coefficient (R2) and the mean difference between SMP and SMPe (i.e., mean square error of prediction). The validation suggests that our model can be used to estimate the herd's SMP with the herd's Cpk. The Cpk equation relates the herd's BMSCC with the EU official SCC limit, thus the logistic regression model enables the adoption of critical limits for subclinical mastitis, taking into consideration the legal standard for SCC.