Association of Mycobacterium avium paratuberculosis serostatus with age at first calving, calving interval and milk production in dairy cows

Mycobacterium avium ssp. paratuberculosis (MAP) is the causative agent of bovine paratuberculosis, also known as Johne's disease. This infection is responsible for negative effects, ranging from reduction of milk production to reproductive compromise and increased susceptibility to other diseases such as mastitis. Contradictory information on the association between this infection and reproductive performance has been reported in dairy cows. The aim of this work was to investigate associations between individual cow MAP seropositivity and lifetime reproduction and production performance. MAP serum ELISA (IDEXX MAP Ac) results from all the 13,071 adult cows present on 191 farms and corresponding birth- and calving-date records obtained from the National Association for Genetic Improvement of Dairy Cattle were used. Cows and farms were classified as positive or negative, based on ELISA results. Outcomes assessed, for all cows and all calvings from first to fifth, were age at first calving (AFC), intercalving intervals (ICI) from first to fourth interval, and average milk production per day of productive cycle (Milk-305/ICI - a ratio between 305 d corrected milk production, for each lactation, and the number of days of the respective ICI). Multilevel mixed models were used to investigate the association of cows' MAP status with AFC, ICI and Milk-305/ICI. Three levels were considered in the models: "measurement occasion," the first level, was nested within cows and cows were nested within farms. The "measurement occasion" is the time point where all the observed measures (between 2 successive parturitions, such as milk production and SCC) were referred to. Our results indicate that MAP positive Cows have a significant 14-d lower mean AFC than MAP negative ones. The overall average ICI in our study was 432.5 d (s.d. 94,6). The average ICI, from 1st to 4th, was not significantly affected by MAP seropositivity. No significant effect of MAP positivity was found on the overall ICI. In relation to Milk-305/ICI, MAP positive cows did not produce significantly less milk than negative cows, across their productive lifetime. We observed higher but non-significant Milk-305/ICI (Kg/day) in MAP positive cows. In our study, the proportion of MAP positive Cows within lactations remained similar across all lactations suggesting that seropositivity did not increased drop-off rate.

Application of a dot blot hybridization assay for genotyping Streptococcus uberis from Brazilian dairy herds

Streptococcus uberis is a major cause of environmental mastitis in many regions, and it is associated with clinical and subclinical infections. Although the main source of infection is the environment, reports of strains with a contagious profile have been described. Dot blot hybridization analysis allows the rapid identification of S. uberis population structures within and between herds, and it helps to identify strain diversity as well as possible clonal lineages that directly affect the control of bovine mastitis caused by this pathogen. The aim of this study was to evaluate the diversity of S. uberis isolates obtained from clinical (n = 22) and subclinical (n = 22) cases of mastitis in dairy herds (n = 13) in Brazil over a period of 12 mo. We submitted 44 S. uberis isolates to dot blot hybridization followed by automatic data analysis. We identified 8 different hybridization patterns using genetic markers associated with virulence factors and taxonomy, indicating diversity of S. uberis within the population and suggesting environmental transmission. However, the evidence of identical dot blot patterns in different mammary quarters from the same animal also suggested local contagious transmission. Of the virulence genes evaluated, we found a high prevalence of the genes sua, pauA, and gapC, highlighting the importance of these virulence factors for the adhesion, invasion, and multiplication of S. uberis in subclinical and clinical intramammary infections.

Attacking Profiles of the Best Ranked Teams From Elite Futsal Leagues

This study aimed to (i) explore the discriminatory power of the task-related variables and the context in establishing differences in the elite futsal leagues of Portugal, Spain, and Russia and (ii) understand how these variables vary according to the match outcome. Methodological issues concerning efficiency (goals and shots), offensive organisation (positional attack, counterattack, set pieces, or 5vs4+Goalkeeper), 1st goal scored during matches (home or away team), match type (balanced or unbalanced), and match outcome (winner, loser, or drawer) were discussed. Archival data were obtained from the 2017–2018 season of Portuguese, Spanish, and Russian professional futsal leagues for all play-off matches. Crosstabs analysis was conducted to establish the significance relationship between the elite futsal leagues and the situational variables. Afterward, discriminant analysis was used to identify the task-related variables that maximise mean differences between different league teams for defining offensive profile, and the variations found when the condition of the winner, loser, or drawer is taken into account. The results allowed to understand that the Portuguese and Russian teams used the positional attacks more, and less the counterattacks and set pieces than the Spaniards, who present a more balanced offensive profile. Overall, winners were better discriminated by goals scored, whereas 5vs4+Goalkeeper strategy discriminated loser teams. Coaches should be aware of these different offensive profiles in order to increase control over the match planning and decrease predictability against opposing teams.

Serum levels of urokinase-type plasminogen activator in healthy dogs and oncologic canine patients

Aim:

Urokinase plasminogen activator (uPA) has been scarcely studied in veterinary oncology. The aim of this study was to determine the uPA serum concentrations in healthy and oncologic canine patients and to investigate its potential value as a tumor biomarker.

Materials and Methods:

Serum uPA concentrations of healthy and oncologic canine patients were measured by enzyme-linked immunosorbent assay. Their relationships with the dogs’ health status and tumor characteristics were analyzed through ANOVA and independent t-test.

Results:

There were no significant differences between mean serum values (±standard deviation) of healthy dogs (0.19±0.13 ng/ml) and oncologic canine patients (0.22±0.33 ng/ml), or between dogs with benign or malignant tumors, and with or without metastases, although the latter tended to show higher uPA serum levels.

Conclusion:

This is the first study describing the uPA serum levels in dogs. Although its results do not support uPA as a tumor biomarker, higher uPA levels in dogs with metastatic neoplasms may reflect the role of the enzyme in tumor progression.