ABSTRACT. The observation of bovine mitochondrial DNA (mtDNA) polymorphisms allows the separation of American zebu cattle, according to its maternal lineage ancestry, into two groups: one with Bos indicus mtDNA and other with Bos taurus mtDNA. The aim of the present study was to determine the productive and reproductive differences between these two groups, in a Guzerat dairy herd. The genotyping of a sample of 56 animals allowed the categorization of most of the 3835 animals in the pedigree file. The production file included 3528 calving and 3198 lactation records from 729 cows, born during the years 1947 to 2007. The traits considered were: lactation milk yield (LMY); days in milk (DIM); age at first calving (AFC), and calving interval (CI). Heritabilities and breeding values were estimated using an animal model. The regression of the average breeding values per year of birth indicated the genetic trends of the herd. The heritability coefficients estimated for LMY, DIM, AFC, and CI were 0.42, 0.43, 0.20, and 0.10, Bos indicus or Bos taurus mitochondrial DNA -Guzerat respectively. The genetic trends were similar for both groups, pointing to an improvement in the productive and a worsening in the reproductive traits. The two groups differed significantly regarding the average estimated breeding values for LMY, DIM and AFC, in the starting period, until 1970, but no differences were observed in the more recent years, after 1970. The segregation between the groups existed in the starting period, probably because the Bos taurus contributions to the herd had occurred more recently at that moment. The conclusion is that mtDNA has no significant effect on these traits.

BackgroundEndogamy increases the risk of manifestation of deleterious recessive genes. Mitochondrial DNA allows the separation of American Zebu (Bos indicus and Bos taurus) and evaluate the effect of mitochondrial DNA on productive traits of cattle. However, the effect of endogamy and mitochondrial DNA (mtDNA) on the immune system remains unclear. The aim of this study was to evaluate the association between endogamy, mtDNA and immune parameters.ResultsA total of 86 cattle (43 cows and 43 calves) were used in this study. Age, endogamy, milk yield, and origin of mtDNA were measured and their influence on immunological parameters was evaluated. Older cows had increased CD4+ T cells, decreased CD21+ and γδhigh T cells as well as increased CD4+/CD8+ and T/B ratio. Multiple regression analysis indicated that endogamy in calves was associated with increased CD8+ T and CD21+ B lymphocytes, and decreased γδhigh T cells in peripheral blood. Cows with medium and lower endogamy had a lower percentage of B lymphocytes and γδlow T cells and cows with lower endogamy had higher levels of γδ T cells and γδhigh T cells, as well as the CD4+/CD48+ cell ratio. Calves with higher endogamy had higher levels of CD8+ T lymphocytes, whereas calves with lower endogamy had lower levels of γδlow T cells.ConclusionsThese results demonstrated for the first time that endogamy influences the immune system of cattle.

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BackgroundTrypanosomiasis is a disease caused by Trypanosoma (Dutonella) vivax, a hemoprotozoa that can affect bovines. In South America, the sanguineous form is mechanically transmitted from one mammalian host (ruminant) to another by the bite of a blood-sucking insect or by needles contaminated with infected blood. The negative impact of the parasitosis caused by T. vivax infection on the reproductive activity of male and female ruminants is known to reduce fertility. In males, alterations such as degeneration, diffuse or interlobular inflammatory infiltrate found in ovine and bovine testicles, can affect fertility through decreased sperm quality. This study evaluated the impact of natural infection with T. vivax on Zebu bulls from the Central Station of Artificial Insemination (CSAI) with regard to libido and the negative effects caused by this protozoan on semen quality.MethodsBlood samples of 44 animals were collected to evaluate the presence of the trypomastigote form of T. vivax in blood smears obtained from hematocrit and buffy coat, and antibody titer IgG anti T. vivax in indirect Immunoflorescence (IFI). Furthermore, data related to libido, ejaculate volume, spermatic concentration, and seminal vigor were recorded for these animals employing the criteria of the CSAI.ResultsNine animals (20.45 %) showed T. vivax trypomastigotes and parasitemia between 0.02 and 0.07, and antibody titers from 1:80 to 1:320 in IFI. Twenty nine negative animals in parasitological tests were not reactive in IFI, and six animals presented the antibodies IgG anti T. vivax in IFI. Data on reproductive activity showed that animals infected with T. vivax have a decreased libido and an increased spermatic volume, whereas other factors related to the reproductive process such as spermatic concentration, motility and spermatic force, were unchanged in infected bulls.ConclusionsThe T. vivax infection in Zebu bulls from CSAI caused patent parasitemia, induced a febrile state, promoted reduction in the libido and increased the ejaculate volume. These conditions together may account to decrease the performance of these animals.

Background:The hematology of turtles of the Amazon, such as the Arrau turtle (Podocnemis expansa), has not been well described in the literature. Referencing how to collect and analyze blood samples is fundamental for the medical practice of these exotic animals. Objectives:The aim of this study was to evaluate the hematologic parameters of Arrau turtles of the Amazon to determine the best anticoagulant (EDTA, citrate, or sodium heparin) and cytologic stain (Giemsa, Quick Panoptic, or Rosenfeld) for use with this species.Methods: Blood samples from eight turtles were collected. Three blood smears were made using blood without anticoagulant, and the rest of the sample was distributed in three tubes, containing EDTA, citrate, and sodium heparin, for erythrogram and leukogram analyses. How to cite this article: Garcia GC, Alves-Júnior JRF, Santana ÁE, et al. Hematologic variables of the Arrau turtle (Podocnemis expansa) under the effects of different anticoagulants and cytologic stains.

ABSTRACT. Differences in cellular and humoral immunity in Zebu (Bos taurus indicus) and European (B. taurus taurus) cattle breeds, which may be related to differences in resistance or susceptibility to infectious or parasitic diseases, are largely unknown. This study aimed to perform a comparative analysis of innate and adaptive immunity of European (including Holstein, Brown Swiss, and Hereford) and Zebu (including Gir, Nelore, and Guzera) breeds, by assessing their peripheral blood leukocyte profiles (i.e., monocytes, eosinophils, and lymphocytes, including CD4 + and CD8 + T cells, and CD21 + B cells). Phenotypic profile of peripheral blood bovine leukocytesHigher frequencies of cells involved in innate immunity were observed in Zebu breeds, particularly monocytes and non-T and non-B cells (13.37 ± 0.9058 and 37.67 ± 1.55, respectively). This finding may contribute to the increased resistance of B. taurus indicus to certain infectious and parasitic diseases. Considering other leukocyte populations in the peripheral blood, among-breed variation was greater than differences between the two subspecies. This study will serve as a basis for further investigations regarding comparative immunology and resistance to infectious and parasitic diseases of cattle.

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Canine otitis externa is a common and recurrent disease in domestic dogs. Although not being life threatening, it can result in the overuse of antibiotics, increased bacterial resistance and reduction of options for treatment. This study aimed to determine: the principal characteristics (age, race, and gender) of dogs affected by otitis externa; the most frequently bacteria identified as being associated with it and their antimicrobial resistance profiles. A total of 221 bacterial isolates were identified by morphological staining and biochemical processes and tested against eleven antibiotics. Among the 148 dogs diagnosed with otitis externa, 51.4% (76/148) were males and 48.6% (72/148) females. The cases were detected mainly in dogs with age above 7 years (54.7%; 81/148. Among the races examined, poodles were the most numerous (14.84%; 22/148). The most common bacteria found were: coagulase-negative Staphylococcus (StCN), 33.9% (75/221); coagulase-positive Staphylococcus (StCP), 19% (42/221); Proteus spp., 17.2% (38/221) and Pseudomonas aeruginosa, 9.5% (21/221). Simultaneous resistance to more than three classes of antimicrobials were most frequently detected in P. aeruginosa (61.9%; 13/21) and Proteus spp (39.47%; 15/38). According to data obtained from this study, two veterinary medications found to be most effective for topical treatment were tobramycin and ciprofloxacin.