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31.
The aim of the present study was to investigate the effects of crossbreeding on collagen content and solubility, shear force (WBSF) and the eating quality of Infraspinatus (INF) and Semimembranosus (SM) muscles of young bulls and the relationships between collagen content and solubility, shear force and the eating quality of beef. The experimental material comprised muscles of crossbred young bulls (about 600 days old) of Polish Holstein‐Friesian (PHF) × Limousine (LM) (n = 10), PHF × Charolaise (CH) (n = 9), PHF × Hereford (HER) (n = 9) breeds. The crossbreeding influenced WBSF, aroma and taste, total, water‐soluble, acid‐soluble, total soluble and insoluble collagen content, as well as the acid‐soluble, total soluble and insoluble collagen proportions. WBSF was significantly negatively correlated with sensorial tenderness and water‐soluble collagen content. The eating quality of beef obtained from different crossbreds was similar; however, the meat from PHF × LM and PHF × HER bulls had lower WBSF values than PHF × CH bulls. © 2016 Japanese Society of Animal Science  相似文献   
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The aim of this study was to analyse and describe the variability of the umbilical artery. Two hundred and thirty‐two pelvic halves from 116 adult dogs were examined. To study the permeability of the umbilical artery, ten adult dogs, nine newborns and thirteen foetuses between 35 and 50 days of gestation were also used. In relation to the origin of the umbilical artery, six anatomical variations were found. From which five involved a cranial (= 4) or caudal (= 1) relocation of its origin, and in one case (= 1), the umbilical artery arose from the median sacral artery. In eight cases, the umbilical artery gave off the prostatic (= 1) or vaginal (= 7) arteries. The permeability of the umbilical artery was the most significant anatomical variation: permeability was detected in 45% (106 of 232 pelvic halves) of all cases, from which 36 were males and 70 females. Interestingly, an equal vascular permeability in both hemipelvises was found for 82% of the dogs, thus additional data related to such feature of the umbilical artery was also recorded. In accordance with the statistical study, the main anatomical variations described showed significant values for gender, side of the body, size and profile variables.  相似文献   
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A total of 417 isolates of Escherichia coli collected from five animal species/organ system combinations from swine [urinary/genital tract (UGT) incl. mastitis metritis agalactia syndrome], horses [genital tract (GT)] and dogs/cats [respiratory tract (RT), UGT and gastrointestinal tract (GIT)] were analysed quantitatively for their susceptibility against different antimicrobial agents by determination of minimum inhibitory concentrations. Regardless of which animal species the strains originated from, resistance appeared most frequently against sulfamethoxazole (18-59%), tetracycline (14-54 %), and ampicillin (14-39%). High percentages of intermediate isolates were observed for cephalothin (39-46 %). In general, low prevalences of resistance were detected for amoxicillin/clavulanic acid (1-4%), gentamicin (1-9%), and cefazolin (0-11%). Generally speaking, the antimicrobial resistance situation among E. coli isolates from horses and small animals is relatively good.  相似文献   
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Adrenomedullin (AM) has been characterized as an endogenous tissue survival factor and modulator of many inflammatory processes. Because of the increased susceptibility of the mammary gland to infection during the time surrounding parturition in the cow, we investigated how milk and tissue content of AM and its binding protein (AM-BP) might be affected by the stage of lactation and the udder health status. Milk and mammary biopsy samples were obtained from Holstein cows 21 days prior to and at various times after calving to represent the dry period and early and mid-stages of lactation. Additional cows received an intramammary challenge with Escherichia coli for immunohistochemical characterization of AM and AM-BP. Milk AM concentrations were relatively constant across the stages of lactation while AM-BP increased two-fold (P<0.04) between early and mid-lactation. Milk AM (P<0.04) and AM-BP (P<0.03) increased as somatic cell counts (SCCs) increased within a given stage of lactation. Tissue content of both (AM and AM-BP) were significantly affected by stage of lactation, lowest in the dry period and progressively increasing to peak at mid-lactation as well as increasing in association with higher levels of SCCs. Following E. coli challenge, AM increased in epithelial cells surrounding mammary alveoli presenting high levels of SCCs. The data suggest that AM and AM-BP are cooperatively regulated in the mammary gland during lactation; changes in localized tissue AM and AM-BP content reflect a dynamic regulation of these tissue factors in the bovine mammary gland consistent with their protective effects within inflamed tissue.  相似文献   
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The purpose of this study was to determine the serological and molecular prevalence of Bartonella spp. infection in a sick dog population from Brazil. At the S?o Paulo State University Veterinary Teaching Hospital in Botucatu, 198 consecutive dogs with clinicopathological abnormalities consistent with tick-borne infections were sampled. Antibodies to Bartonella henselae and Bartonella vinsonii subsp. berkhoffii were detected in 2.0% (4/197) and 1.5% (3/197) of the dogs, respectively. Using 16S-23S rRNA intergenic transcribed spacer (ITS) primers, Bartonella DNA was amplified from only 1/198 blood samples. Bartonella seroreactive and/or PCR positive blood samples (n=8) were inoculated into a liquid pre-enrichment growth medium (BAPGM) and subsequently sub-inoculated onto BAPGM/blood-agar plates. PCR targeting the ITS region, pap31 and rpoB genes amplified B. henselae from the blood and/or isolates of the PCR positive dog (ITS: DQ346666; pap31 gene: DQ351240; rpoB: EF196806). B. henselae and B. vinsonii subsp. berkhoffii (pap31: DQ906160; rpoB: EF196805) co-infection was found in one of the B. vinsonii subsp. berkhoffii seroreactive dogs. We conclude that dogs in this study population were infrequently exposed to or infected with a Bartonella species. The B. henselae and B. vinsonii subsp. berkhoffii strains identified in this study are genetically similar to strains isolated from septicemic cats, dogs, coyotes and human beings from other parts of the world. To our knowledge, these isolates provide the first Brazilian DNA sequences from these Bartonella species and the first evidence of Bartonella co-infection in dogs.  相似文献   
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Phenotypic variation in organisms depends on the genotype and the environmental constraints of the habitat that they exploit. Therefore, for marine species inhabiting contrasting aquatic conditions, it is expected to find covariation between the shape and its spatial distribution. We studied the morphology of the head and cephalic sensory canals of the eelpout Austrolycus depressiceps (4.5–22.5 cm TL) across its latitudinal distribution in South Pacific (45°S–55°S). Geometric morphometric analyses show that the shape varied from individuals with larger snout and an extended suborbital canal to individuals with shorter snouts and frontally compressed suborbital canal. There was size variation across the sampled populations, but that size does not have a clear latitudinal gradient. Only 8% of the shape variation relates to this size variation (allometry), represented by a decrease in the relative size of the eye, and a depression of the posterior margin of the head. There were spatial differences in the shape of the head, but these differences were probably caused by allometric effects. Additionally, 2 of the canals of the cephalic lateralis pores and the head shape showed modularity in its development. This study shows that the morphology of marine fish with a shallow distribution varies across distances of hundreds of kilometers (i.e., phenotypic modulation).  相似文献   
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Irrigation techniques that reduce water applications are increasingly applied in areas with scarce water resources. In this study, the effect of two regulated deficit irrigation (RDI) strategies on peach [Prunus persica (L.) Batsch cv. “Catherine”] performance was studied over three growing seasons. The experimental site was located in Murcia (SE Spain), a Mediterranean region. Two RDI strategies (restricting water applications at stage II of fruit development and postharvest) based on stem water potential (Ψs) thresholds (?1.5 and ?1.8 MPa during fruit growth and ?1.5 and ?2.0 MPa during postharvest) were compared to a fully irrigated control. Soil water content (θv), Ψs, gas exchange parameters, vegetative growth, crop load, yield and fruit quality were determined. RDI treatments showed significantly lower values of θv and Ψs than control trees when irrigation water was restricted, causing reductions in stomatal conductance and photosynthesis rates. Vegetative growth was reduced by RDI, as lower shoot lengths and pruning weights were observed under those treatments when compared to control. However, fruit size and yield were unaffected, and fruit quality was slightly improved by RDI. Water savings from 43 to 65 % were achieved depending on the year and the RDI strategy, and no negative carryover effect was detected during the study period. In conclusion, RDI strategies using Ψs thresholds for scheduling irrigation in mid–late maturing peach trees under Mediterranean conditions are viable options to save water without compromising yield and even improving fruit quality.  相似文献   
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