In dairy cattle, mastitis is a disease of the mammary gland caused by pathogens such as bacteria, viruses, fungi, and algae. Mastitis causes economic losses to dairy farms as well as public health concerns. The reproductive efficiency of commercial dairy herds has important implications for the economic success of dairy operations and is strongly associated with the health status of cows. Mastitis has previously been linked with decreased fertility of dairy cows, but the effect of specific pathogens on the severity of fertility reduction is still unclear. In this study, cows diagnosed with mastitis caused by major pathogens (Staphylococcus aureus, Streptococcus agalactiae, Escherichia coli, Klebsiella spp., Mycoplasma spp., and environmental Streptococcus) needed more artificial inseminations (AI) than did cows with mastitis caused by minor pathogens (coagulase-negative Staphylococcus and Corynebacterium spp.) and healthy cows. Cows diagnosed with mastitis, independent of what pathogen was causing mastitis, had more days open compared with nonmastitic cows. The percentage of cows that successfully established pregnancy at first AI was greater for the control group than for the major pathogens group but not significantly different from the minor pathogens group. Pregnancy loss was lower in the control group than in the major pathogens group; however, there was no difference compared with the minor pathogen group. Mastitis caused by gram-negative bacteria decreased the percentage of pregnancy per first AI and increased days open and pregnancy loss compared with the control group. Cows with mastitis caused by gram-positive bacteria also had increased days open compared with control cows. This study shows that different mastitis-causing bacteria can affect the fertility of cows differently. Mastitis events caused by major pathogens and gram-negative bacteria were associated with the greatest decrease in reproductive efficiency.

Coxiella burnetii, the zoonotic agent of Q fever, has a worldwide distribution. Despite the vast information about the circulating genotypes in Europe and North America, there is a lack of data regarding C. burnetii strains in South America. Here, we show the presence of novel multispacer sequence typing (MST) genotypes of C. burnetii in two clusters detected in Brazil and Argentina that seem to be distant in parenthood. Argentinian strains isolated from a tick belongs to a new phylogenetic branch of C. burnetii, and the Brazilians strains may be related to MST 20 and 61. Multilocus variable number tandem repeats analysis (MLVA) typing provided a deeper resolution that may be related to host clusters of bovines, caprine, ovine, and ticks. Our results corroborate with the reports of geotypes of C. burnetii. Thus, we highlight the need for more genotyping studies to understand the genetic diversity of C. burnetii in South America and to confirm the hypothesis of host-related genotypes. We also emphasize the importance of virulence studies for a better understanding of Q fever in the region, which may help in surveillance and disease prevention programs.

Among the new diagnostic methods for mastitis detection under development, milk acute-phase proteins (APPs) are receiving special attention. The study aimed to compare the profile of milk APPs from cows with natural clinical mastitis caused by distinct pathogens. The concentrations of haptoglobin (Hp), serum amyloid A (SAA), alpha-1-acid glycoprotein (AGP), and C-reactive protein (CRP) were measured by Spatial Proximity Analyte Reagent Capture Luminescence (SPARCL). Each APP was compared across the pathogens causing mastitis. The APPs differed statistically (p < 0.05) among the pathogens causing udder infection. There were significant and positive correlations among the concentration profile, for each pathogen, in three of four APPs studied. It can be concluded that the pathogen causing mastitis could modify the profile of release of the APPs in milk. The profile of Hp, AGP, and CRP demonstrated significant correlation, indicating that the three APPs are suggested as biomarkers, in milk, for bovine mastitis.

Escherichia coli is a major pathogen involved in the etiology of environmentally derived bovine mastitis and is characterized by a variety of virulence factors (VF). Mammary infections with E. coli have shown a wide range of clinical signs, causing changes in milk (score 1, or mild), abnormal appearance of milk and udder inflammation (score 2, or moderate), and abnormalities in milk, udder inflammation, and systemic signs of illness (score 3, or severe). Nevertheless, to date, the profile of the genes related to the virulence of the pathogen in mammary infections and the severity scores of cases have not been thoroughly elucidated. Therefore, a panel of 18 virulence-encoding genes associated with extra-enteric pathogenicity of E. coli (ExPEC) were investigated in addition to in vitro swimming and swarming motility profiles and antimicrobial susceptibility/ resistance patterns among 114 E. coli strains isolated from cows with clinical mastitis and different severity scores. Of 114 clinical cases, 39.5, 54.4, and 6.1% were mild, moderate, and severe, respectively. The main genes related to VF harbored by isolates were adhesins (fimH 100%; ecpA 64.0%, fimA 31.6%), serum resistance (traT 81.6%; ompT 35.1%), siderophores (irp2 9.6%), and hemolysin (hlyA 7%). Among the isolates studied, 99.1% showed in vitro resistance to bacitracin and cloxacillin, and 98.2% to lincosamin. Of the total isolates, 98.2% were considered multidrug resistant based on the multiple antimicrobial resistance index. No significant difference was observed between mean swimming (13.8 mm) and swarming (13.5 mm) motility, as well as severity scores of clinical mastitis and the ExPEC genes studied. The isolation of strains resistant to various antimicrobials, even though tested only in vitro, highlights the importance of rational use of antimicrobials for mastitis treatment. The high prevalence of the genes related to serum resistance (traT and ompT) and adhesion (ecpA) of the pathogen, in addition to main associations between the genes fimH, ecpA, and traT among cows with severity scores of 1 (15%) and 2 (22.6%), indicates that the genes traT, ecpA, and ompT could be further studied as biomarkers of ExPEC for clinical intramammary infections. In addition, the Ex-PEC genes ompT (protectin), ibe10 (invasin), and ecpA (adhesin) were investigated for the first time among cows with mastitis, where scores of clinical severity were assessed. Results of this study contribute to the characterization of virulence mechanisms and antimicrobial resistance profile of ExPEC variants that affect dairy cows with different scores of clinical mastitis.

We investigated the genes kpsMTII, iucD, sfaDE, afaBC, papA and papC, (proposed to be involved in extra‐intestinal pathogenic Escherichia coli—ExPEC), phylogroup classification and the in vitro swimming and swarming motility in 50 E. coli isolated from bovine mastitis with different clinical severity scores (mild, moderate and severe). The aforementioned genes were detected in 12 (n = 12/50; 24·0%) isolates. kpsMTII and iucD were the most frequent genes identified in six (n = 6/50; 12·0%) and four (n = 4/50; 8·0%) of the isolates, respectively. In only one (n = 1/50; 2·0%) isolate, more than one gene was simultaneously identified: iucD and kpsMTll were detected whereas sfaDE and afaBC were not detected. Mild, moderate and severe clinical signs were observed in 40·0% (n = 20/50), 28·0% (n = 14/50) and 32·0% (n = 16/50) of the cases. Commensal phylogroups B1 (n = 19/50; 38·0%) and A (n = 19/50; 38·0%) were prevalent; whereas pathogenic phylogroups B2 and D were observed in only 10·0% (n = 5/50). Swarming and swimming motilities were observed in 90·0% (n = 45/50) and 68·0% (n = 34/50) of the isolates, respectively; and there was a significant association (P = 0·0036) between swarming motility and severe clinical cases (score 3). To the best of our knowledge, this is the first study where clinical severity of bovine mastitis cases and the genes proposed to classify ExPEC were assessed in relation to swarming and swimming motility. Significance and Impact of the Study Escherichia coli is classified as extra‐intestinal (ExPEC) when strains contain at least two of the genes kpsMTII, iucD, sfaDE, afaBC and papA and/or papC. We investigated in vitro motility and the presence of these genes in 50 E. coli isolated from bovine mastitis with different clinical scores (mild, moderate and severe). Clinical severity was not associated with the genes studied. Swarming motility was associated with severe cases (score 3) of clinical mastitis. Results of this study contribute to a better understanding of the factors that determine the severity of clinical mastitis.

There is evidence that regulation of follicle selection in cattle involves locally produced growth factors. In the present study, we investigated the expression of members of the fibroblast growth factor (FGF) 7 family during follicle deviation. The largest and second largest follicles were recovered during the second day of a synchronised follicle wave and the future dominant and future subordinate follicles were identified based on diameter and cytochrome P450, family 19, subfamily A, polypeptide 1 (CYP19A1) mRNA levels in granulosa cells. Theca cells of the future dominant follicle contained less mRNA encoding FGF7 and FGF10 compared with those from the future subordinate follicle 2.5 days after ovulation, before a significant difference between the diameters of the future dominant and future subordinate follicles could be observed, but FGF22 mRNA levels did not change. Levels of mRNA encoding FGF receptors FGFR1B and FGFR2B in theca and granulosa cells, respectively, were lower in the future dominant follicle compared with the future subordinate follicle. Addition of FGF10 to granulosa cells in vitro significantly decreased oestradiol secretion, as well as CYP19A1, FSH receptor (FSHR) and insulin-like growth factor 1 receptor (IGF1R) mRNA abundance, whereas FGF22 had no effect. We conclude that FGF10 and FGFR2B expression is increased in the future subordinate follicle before morphological deviation, which may contribute to follicle selection.

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This study aimed to determine the occurrence of gastrointestinal and pulmonary parasites in calves and to evaluate seasonal and age patterns in parasitism. For this, we used 140 clinically healthy crossbreed calves (two to 12 months old) that belonged to two private farms in the municipalities of Botucatu (n=53) and Manduri (n=87), São Paulo state, Brazil. The calves were monitored for 12 months (from September 2014 to August 2015). Fecal samples were collected directly from the rectum every three months. Fecal egg counts were determined using the modified McMaster technique with a sensitivity of 50 eggs per gram of feces (EPG). Coproculture was performed on pooled samples to identify Strongylida infective larvae. First-stage larvae of Dictyocaulus viviparus were extracted by a modified Baermann method. The data showed non-normal distribution (Shapiro-Wilk) and the nonparametric Kruskall-Wallis test was employed to evaluate the EPG data by seasons and age groups. Dunn’s post-test was used for multiple comparisons (P<0.05). The calves from Manduri farm showed significantly higher fecal egg counts (P<0.0001) in the winter when compared to other seasons. At Botucatu farm, young calves (2-3 months old) showed significantly higher EPG than old calves (8-12 months) (P=0.01). The prevalence and overall mean of animals positive for Strongylida type-eggs were 81.1% and 340 in Botucatu, respectively, versus 83.9% and 854 in Manduri, respectively. Furthermore, we found Strongyloides spp., Moniezia spp., and Trichuris spp. eggs and Eimeria spp. oocysts. The prevalent genera in all coprocultures in decreasing order were: Cooperia spp., Haemonchus spp., Oesophagostomum spp., and Trichostrongylus spp. First-stage larvae of Dictyocaulus viviparus were found only in Botucatu farm samples throughout the year, except in spring.