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1.
The aim of this study was to estimate genetic parameters for different precocious calving criteria and their relationship with reproductive, growth, carcass and feed efficiency in Nellore cattle using the single‐step genomic BLUP. The reproductive traits used were probability of precocious calving (PPC) at 24 (PPC24), 26 (PPC26), 28 (PPC28) and 30 (PPC30) months of age, stayability (STAY) and scrotal circumference at 455 days of age (SC455). Growth traits such as weights at 240 (W240) and 455 (W455) days of age and adult weight (AW) were used. Rib eye area (REA), subcutaneous fat thickness (SFT), rump fat thickness (RFT) and residual feed intake (RFI) were included in the analyses. The estimation of genetic parameters was performed using a bi‐trait threshold model including genomic information in a single‐step approach. Heritability for PPC traits was moderate to high (0.29–0.56) with highest estimates for PPC24 (0.56) and PPC26 (0.50). Genetic correlation estimates between PPC and STAY weakened as a function of calving age. Correlation with SC455, growth and carcass traits were low (0.25–0.31; ?0.22 to 0.04; ?0.09 to 0.18, respectively), the same occurs with RFI (?0.09 to 0.08), this suggests independence between female sexual precocity and feed efficiency traits. The results of this study encourage the use of PPC traits in Nellore cattle because the selection for such trait would not have a negative impact on reproductive, growth, carcass and feed efficiency indicator traits. Stayability for sexual precocious heifers (PPC24 and PPC26) must be redefined to avoid incorrectly phenotype assignment.  相似文献   
2.
Proteomic analysis of mare uterine flush fluid provides a minimally invasive technique for studying protein changes associated with the oestrous cycle. The aim of this study was to identify differentially abundant proteins in the uterine flush fluid of mares in oestrus and dioestrus. In this study, uterine flush fluid samples were collected from eight reproductively healthy mares in either oestrus (n = 5) or dioestrus (n = 3). Proteomic analysis was performed using liquid chromatography‐tandem mass spectrometry. Of 172 proteins identified, six proteins (immunoglobulin lambda‐like polypeptide 1, haemoglobin subunit alpha, alpha‐1B‐glycoprotein, serotransferrin, apolipoprotein A‐1, and haemoglobin subunit beta) were significantly more abundant in oestrus. These proteins may contribute to the endometrial defence system through roles in inflammation, immunity or antimicrobial activity. In other species, some of these proteins have been described as immunoglobulins, negative acute phase proteins or defence agents against micro‐organisms. During dioestrus, immunoglobulin alpha‐1 chain C region‐related, complement factor I, CD 109 antigen and uterocalin, were significantly more abundant. Research in other species suggests that these four proteins contribute to the immune response through proposed immunoregulatory characteristics, complement system involvement or roles in B cell–T cell interactions. In conclusion, ten differentially abundant proteins were identified in the uterine flush fluid of mares in oestrus and dioestrus. Targeted studies on these proteins could elucidate their role in uterine defence mechanisms during the oestrous cycle in the mare.  相似文献   
3.
Dogs naturally infected with Leishmania Infantum (=L. chagasi) were treated with miltefosine using different therapeutic regimens. The animals were evaluated for clinical evolution, biochemical parameters, parasite load (by real-time PCR), cytokine levels and humoral response. After treatment and during the following 24 months, there was progressive clinical improvement and complete recovery in 50% (7/14) of the treated animals. There was a decrease in the smear positivity of the bone marrow after treatment, and there was also a gradual and constant decrease in positive cultures at the end of the follow-up period. However, the PCR detection of parasite DNA remained positive. In general, all animals presented a significant increase in parasite load 6 months after treatment. The IFN-γ levels in all the groups tended to increase during follow-up period, regardless of the miltefosine dose administered. The IL-4 and IL-10 levels of the animals tended to decrease during follow-up, except after 300 days when only IL-10 increased. The serum antibodies identified antigens that ranged from 116 kDa to less than 29 kDa in the Western blot assay. Furthermore, 300 days after treatment, qualitative and quantitative differences in the antigen profiles were observed. Antigens of 97 and 46 kDa were the most intensely recognized. Higher levels of antigen-specific Leishmania IgG were detected before and 300 days after treatment in all groups. Taking together, the improvement in the clinical symptoms was not followed by parasitological clearance, suggesting that treatment with miltefosine is not recommended, especially in endemic areas like Brazil, where children are the major victims and dogs are involved in the maintenance of the parasite cycle.  相似文献   
4.
Our lack of understanding of the immune microenvironment in canine osteosarcoma (cOSA) has limited the identification of potential immunotherapeutic targets. In particular, our ability to utilize readily available tissue from a dog's primary tumour to predict the type and extent of immune response in their pulmonary metastatic lesions is unknown. We, therefore, collected 21 matched pairs of primary tumours and pulmonary metastatic lesions from dogs with OSA and performed immunohistochemistry to quantify T‐lymphocyte (CD3), FOXP3+ cell, B‐lymphocyte (Pax‐5), and CD204+ macrophage infiltration. We found that T‐lymphocytes and FOXP3+ infiltrates in primary tumours positively correlated with that of metastatic lesions (ρ = 0.512, P = 0.038 and ρ = 0.698, P = 0.007, respectively), while a strong trend existed for CD204+ infiltrates (ρ = 0.404, P = 0.087). We also observed T‐ and B‐lymphocytes, and CD204+ macrophages to be significantly higher in a dog's pulmonary metastasis compared to their primary tumour (P = 0.018, P = 0.018, P = 0.016, respectively), while FOXP3+ cells were only significantly higher in metastases when all primary tumour and metastasis lesions were compared without pairing (P = 0.036). Together, these findings suggest that the metastatic immune microenvironment may be influenced by that of the primary cOSA, and that primary tumour immune biomarkers could potentially be applied to predict immunotherapeutic responses in gross metastatic disease. We, therefore, provide a rationale for the treatment of cOSA pulmonary metastases with immunotherapeutics that enhance the anti‐tumour activity of these immune cells, particularly in dogs with moderate to high immune cell infiltration in their primary tumours.  相似文献   
5.
6.
This report describes a case of cutaneous pythiosis in a 6‐year‐old female mixed breed dog, from the central west region of São Paulo State, Brazil. The cytological and histopathological analyses showed an intense inflammatory infiltrate with presence of numerous hyphal elements, suggesting infection due to Pythium insidiosum. The diagnosis was confirmed by nested‐PCR, which was carried out with specific primers derived from the ribosomal DNA region. The pathogen occurs in Brazil and veterinarians should be aware of the importance of correctly diagnosing this disease and differentiating it from other fungal diseases.  相似文献   
7.
Three Meriones species inhabit Tunisia, namely M. shawi, M. libycus and M. crassus, but little genetic data exist on these gerbils. We collected Meriones from eight localities in Tunisia, and obtained mitochondrial (cytochrome b) and nuclear (IRBP) gene sequence data for 37 and 13 specimens, respectively, belonging to two species: M. shawi and M. libycus. We also optimised three microsatellite markers previously described in M. unguiculatus to obtain a finer analysis of their genetic diversity and geographic structure, given their wide distribution. Phylogenetic inferences of cyt b and IRBP data for these species, in the context of other gerbillin data, corroborate their taxonomic affinities reported by previous studies. High cyt b haplotype diversity was observed in both species (25 haplotypes in 29 and 27 sequences for M. shawi and M. libycus, respectively) with little geographical structure for M. shawi but three divergent groups in M. libycus. The average microsatellite diversity within each population was high (HO ≥ 0.6, HE ≥ 0.8) with M. libycus populations attaining the highest values. Population differentiation was moderate for several population pairs (Fst ≥ 0.1), the highest being between M. shawi populations. However, genetic distance among populations was not significantly correlated with geographic distance in either M. shawi or M. libycus. Our results contribute to a better characterisation of Tunisian Meriones species, suggesting high geographic structure in mtDNA of M. libycus populations within North Africa.  相似文献   
8.

Background

People with critical illness (CI) commonly develop various forms of immune dysfunction, however, there is limited information concerning immune dysfunction in dogs with CI.

Hypothesis

The immune response in CI dogs differs from that of healthy dogs.

Animals

Immunologic variables were compared between 14 dogs with CI, defined as APPLEfast score of >20 points, admitted to the University of Missouri Veterinary Health Center Small Animal Clinic Intensive Care Unit and healthy controls (n = 15).

Methods

Cohort study evaluating constitutive and lipopolysaccharide (LPS)‐stimulated TNF‐α, IL‐6, and IL‐10 production, phagocytosis of opsonized E. coli and respiratory burst capacity after opsonized E. coli or phorbol 12‐myristate 13‐acetate (PMA) stimulation, peripheral blood lymphocyte phenotype, and monocyte expressions of HLA‐DR and TLR‐4.

Results

Lipopolysaccharide‐stimulated leukocyte TNF‐α (median, Q1, Q3; CI, 49, 49, 120; control, 655, 446, 1174 pg/mL; P = < 0.001), IL‐6 (median, Q1, Q3; CI, 49, 49, 64; control, 100, 49, 166 pg/mL; P = 0.029), and IL‐10 (CI, 49, 49, 56; control, 96, 49, 203 pg/mL; P = 0.014) production and both E. coli (median, Q1, Q3; CI, 60.5, 43, 88.5; control, 86.6, 81, 89.2%; P = 0.047) and PMA (CI, 40, 11.7, 70; control, 93, 83, 97.6%; P = < 0.001)‐stimulated respiratory burst capacity significantly decreased in CI dogs. Percentage of monocytes expressing TLR‐4 greater in the CI dogs (median, Q1, Q3; CI, 46.9, 24.3, 64.2; control, 16.4, 9.4, 26.2%; P = 0.005).

Conclusion

These findings suggest dogs with CI develop immune system alterations that result in reduced respiratory burst function and cytokine production despite upregulation of TLR‐4.  相似文献   
9.
Neophysopella tropicalis, one of the causal agents of Asian grapevine leaf rust (AGLR), can cause severe epidemics in Brazil that lead to yield losses in commercial vineyards. An early detection of the pathogen by air sampling of urediniospores on spore traps or in symptomless leaves would be valuable to multiple studies, such as epidemics modelling, risk forecasting, monitoring of pathogen introductions in rust-free areas, and predicting the beginning of epidemics. This study developed a quantitative PCR (qPCR) protocol to quantify N. tropicalis urediniospores attached to adhesive tapes and in grapevine leaves before symptom appearance. A specific primer pair was designed based on the internal transcribed spacer (ITS) sequence region of the AGLR pathogen. Standard amplification curves using genomic DNA from urediniospores of N. tropicalis and from urediniospores attached to adhesive tapes were established. Grapevine leaves inoculated with N. tropicalis were collected at 2, 5, and 7 days postinoculation (dpi). One primer pair (580F/720R) amplified a 140 bp product in all AGLR isolates but did not amplify products of other rust genera, such as Phakopsora, Puccinia, Hemileia, Tranzschelia, Cerotelium, and Coleosporium. As little as 0.1 pg DNA and 10 urediniospores of N. tropicalis attached to adhesive tapes could be detected. qPCR enabled the detection of the pathogen as early as 2 dpi, before symptom appearance. This method can be used to monitor N. tropicalis inoculum in grapevine-growing areas and to quantify symptomless infections of the AGLR pathogen.  相似文献   
10.
A 24‐day‐old Friesian colt died suddenly and a physical examination the morning the foal died showed no abnormalities and serum IgG levels >8.0 g/l. Necropsy examination revealed haemopericardium and a 2 cm transverse tear at the root of the aorta. The foal was also found to have Chlamydophila spp. in the epithelium and Balantidium coli on the mucosal surface of the large colon. An aortic rupture is a novel finding in a foal, colonic Chlamydiosis has not been previously reported in horses and Balantidium coli has not been reported in equids in North America.  相似文献   
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