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31.
This study compared vitamin A, vitamin E, selenium (Se), and L-lactate in blood and synovial fluid in 2 groups of 6 dogs; a control group (without OA) and an osteoarthritic group with spontaneous cranial cruciate ligament rupture and OA. Concentrations of vitamin E were significantly higher in serum than in synovial fluid in both OA (P = 0.006) and control (P = 0.0008) groups. Vitamin E concentration in synovial fluid was significantly higher in the OA group than in the control group (P = 0.009). Concentrations of Se were significantly higher in serum than in synovial fluid in both OA (P = 0.003) and control (P = 0.0006) groups. There were no significant differences in levels of Se, vitamin A, and L-lactate between the 2 groups. This is the first study to show an increased concentration of vitamin E in the synovial fluid of dogs with OA compared with dogs that did not have OA.  相似文献   
32.
This study was aimed at assessing the changes in sperm motion patterns and the percentage of acrosome reaction (AR) in domestic cat semen after treatment with either ionomycin or progesterone (P4). Ten ejaculates were collected from five tomcats using an artificial vagina, and were diluted, centrifuged and resuspended in a capacitation medium. Samples were evaluated and divided into seven equal aliquots and, after 2 h at 25°C, were incubated for 30 min at 38°C in 5% CO2 and then analyzed. Computer-assisted sperm analysis and a combination of three fluorescent probes were used to assess sperm plasma, acrosomal membrane integrity and mitochondrial transmembrane potential. Thirty minutes after the start of incubation, P4 was added (10 μg/ml) to the P1 group. Groups P2 and P3 were supplemented with P4 (10 and 20 μg/ml, respectively) only after 2 h of incubation, and groups I1 and I2 were supplemented with ionomycin (4 and 8 μ m , respectively) 2 h after incubation. Group E was supplemented with ethanol (0.6%) at 2 h after incubation and group C received no supplementation. Ionomycin and P4 treatments led to a hyperactivation-like sperm motion and an increase (p < 0.05) in the percentage of AR. Although a higher (p < 0.05) percentage of AR was obtained in group I2 when compared with all P4 groups, a decrease (p < 0.05) in total and progressive motility was observed in I2 group. As I1 group was similar to I2 to induce AR without diminishing sperm motility, we can conclude that ionomycin at 4 μ m seems to be more suitable to trigger AR in domestic cat sperm.  相似文献   
33.
A recombinant luteinizing hormone-releasing hormone (LHRH) fusion protein was evaluated for its effectiveness in suppression of estrus in heifers. Eight heifers were randomly assigned to two equal treatment groups. Treatments consisted of recombinant ovalbumin-LHRH-7 or recombinant ovalbumin (control). This recombinant chimeric fusion protein consisted of ovalbumin with seven LHRH peptides (ovalbumin-LHRH-7). The plasmid for this protein was expressed in E. coli and was collected and purified as an insoluble protein. One milligram of the respective proteins was suspended in 2 mL of Z-Max adjuvant and administered by intramammary injection three times at 7-wk intervals. Luteinizing hormone-releasing hormone antibody binding was elevated in heifers treated with ovalbumin-LHRH-7 compared to ovalbumin-treated heifers (P < .05). Serum progesterone concentrations (< 1 ng/mL) indicate that the estrous cycle of the four heifers treated with ovalbumin-LHRH-7 was suppressed for a time period ranging from 60 to 238 d, which was different from control heifers (P < .01). Serum progesterone for the control heifers continued to exhibit cyclic profiles over the experimental period. This preliminary study in heifers demonstrated that a chimeric LHRH fusion protein induced elevated concentrations of circulating LHRH antibodies that suppressed estrus for an average of 122 +/- 41 d.  相似文献   
34.
Olive oil extraction generates olive cake (OC) that could be used in ruminant feeding. However, the chemical composition of OC is affected by multiple factors, being therefore highly variable. The objective of this study was to analyse the influence of storage time and further processing: crude, exhausted (subjected to a second oil extraction) and cyclone (obtained from a cyclone separator) on nutritive value of OC samples. Twelve samples (six crude and six exhausted) were obtained monthly from the same pond from 1 to 6 storage months, and nine samples (three crude, three exhausted and three cyclone) were obtained monthly from a different pond from 6 to 9 months storage. Chemical composition was analysed, and OC samples were fermented in vitro with sheep rumen fluid. Increasing storage time up to 6 months decreased sugars and total soluble polyphenols content but increased fibre content in OC. Dry matter effective degradability (DMED) decreased linearly (p < 0.001) by 35.9 and 45.5% as storage time augmented from 1 to 6 months for crude and exhausted OC, respectively. Crude OC had lower DMED values than exhausted OC (averaged values 0.255 and 0.294 g/g, respectively). Both potential production and rate of gas production were lower (p ≤ 0.018) in crude compared with exhausted OC, which was attributed to the high fat content of crude OC (≥86 g/kg dry matter). For samples stored longer than 6 months, cyclone had greater (p < 0.05) DMED than crude and exhausted OC (averaged values 0.207, 0.164 and 0.164 g/g, respectively). The results indicate that ruminal degradability of OC is reduced with advancing storage time, but only subtle changes were observed during the first two months. Cyclone showed greater degradability than crude and exhausted OC, but differences between crude and exhausted OC became negligible after five storage months.  相似文献   
35.
Pharmacokinetics of dexamethasone and prednisolone were studied in 6 horses given dexamethasone alcohol (IV or IM) or dexamethasone 21-isonicotinate as a solution IV or IM (50 micrograms/kg of body weight), prednisolone 21-sodium succinate IV or IM (0.6 mg/kg of body weight), or prednisolone acetate IM (0.6 mg/kg of body weight). Plasma concentrations were determined using a high-performance liquid chromatographic method. After dexamethasone alcohol (IV) or dexamethasone 21-isonicotinate (IV), the half-life of elimination was similar (53 minutes) for both formulations. After dexamethasone (alcohol and isonicotinate, IM), concentrations were low or nondetected. After prednisolone 21-sodium succinate (IV), the half-life of elimination (99.5 minutes) was significantly (P less than 0.01) longer than that for dexamethasone. After prednisolone 21-sodium succinate (IM), absorption was rapid and bioavailability was high. After prednisolone acetate (IM), absorption was slow and prednisolone was present in plasma for about 7 days. Due to the nonlinearity of prednisolone kinetics, a bioavailability higher than 100% was obtained. The basal plasma hydrocortisone concentration was approximately 70 ng/ml. After dexamethasone (IV or IM), plasma hydrocortisone values decreased after a 2-hour delay and returned to base line after a 3 to 4 day delay. After prednisolone 21-sodium succinate (IV or IM), plasma hydrocortisone decreased immediately (IV) or rapidly (IM) and returned to base line after a 24-hour delay. After prednisolone acetate (IM), plasma hydrocortisone decreased for up to 21 days.  相似文献   
36.
Leishmaniasis is kept in nature by the participation of several animal species. This study evaluated the presence of Leishmania spp. in skin samples of free-ranging marsupials Micoureus paraguayanus (n=95) and Didelphis albiventris (n=191), captured in Morro do Diabo State Park and in sections of its surrounding forest, in the region of Pontal do Paranapanema, S?o Paulo State, Brazil. The samples were tested for the presence of kDNA of Leishmania spp. by polymerase chain reaction (PCR) and by real time PCR (qPCR). All samples from D. albiventris tested by PCR were negative for the presence of kDNA of Leishmania spp. However, when tested by qPCR, the positivity was 1.6%. A positivity of 7.4% by PCR and 11.6% by qPCR was observed for M. paraguayanus. Sixty-four per cent (9/14) of positive animals were limited to the same forest fragment. Presence of Leishmania (Leishmania) amazonensis and Leishmania (Viannia) braziliensis was detected in M. paraguayanus samples. While D. albiventris is the most studied marsupial species due to its urban habits, other marsupial species such as M. paraguayanus can be potential reservoirs of Leishmania spp. and should also be studied.  相似文献   
37.
Background: Progesterone receptor (PR) antagonist aglepristone (RU534) has been used successfully for pregnancy termination and therapy of pyometra, vaginal tumors, and mammary hyperplasia in bitches and queens. All of these conditions share with canine mammary carcinomas the expression of PR. Objectives: To study the effect of RU534 on proliferation and apoptosis in canine mammary carcinomas in relation to PR expression. Animals: Twenty‐seven nonspayed bitches with mammary carcinomas were treated with either 2 doses of 20 mg/kg RU534 (n = 22, RU534‐treated group) or oil placebo (n = 5, control group) on days 1 and 8. Methods: Tumor samples were collected before (day 1) and after (day 15) treatment for immunohistochemistry. PR expression, proliferation index (PI), and apoptotic index (AI) were determined using antibodies against PR, Ki67, and cleaved lamin A/C antigens, respectively. The effect of treatment on these parameters was analyzed. Results: Differential expression of PR between day 1 (59.1% PR‐positive tumors) and day 15 (36.4% PR‐positive tumors) was observed in RU534‐treated tumors exclusively. After RU534 treatment, mean PI was significantly decreased in PR‐positive but unchanged in PR‐negative RU534‐treated tumors. A reduction of ≥20% in PI was found in 61.5% of RU534‐treated tumors with PR expression. Conversely, no effect on AI was observed after RU534 treatment. Conclusions and Clinical Importance: Neoadjuvant RU534 treatment had PR expression‐related inhibiting effects on proliferation of canine mammary carcinoma cells.  相似文献   
38.
The rate of osteogenesis was studied in 8 non-pregnant, non-lactating Friesian dairy sheep, 3–6 years old, by means of a treatment with 3 different bone seeking agents. Four sheep were fed a low calcium ration (LCa : 1.8 g Ca/d) and four other sheep a high calcium ration (HCa : 12.7 g Ca/d). The bone markers, oxytetracycline-HCl, alizarine-complexon and demeclocycline-HCl, were administred at intervals of 6 weeks, and the sheep were killed 1 week after administration of the last marker. In undecalcified cross sections from the middle of ribs 2, 10 and 12, and from the proximal and distal parts of rib 10, the numbers of labelled osteons and the number of osteons with 1, 2 or 3 markers were counted under fluorescent microscopy.In the ribs of sheep from the LCa group, the number of labelled osteons and the quantity of labels per osteon tended to be higher than those of sheep from the HCa group. When osteogenic activity was compared in the different sites of ribs analysed, lowest osteogenic activity was observed in the proximal part of the 10th rib.The use of fluorescing markers offers the possibility of studying osteogenic activity over a certain period of time in adult sheep.  相似文献   
39.
Although the second largest chromosome of the genome, the X chromosome is usually excluded from genome-wide association studies (GWAS). Considering the presence and importance of genes on this chromosome that are involved in reproduction, the aim of this study was to evaluate the effect of its inclusion in GWAS on reproductive traits (scrotal circumference [SC], early pregnancy [P16] and age at first calving [AFC]) in a Nelore herd. Genotype data from 3,263 animals with the above-mentioned phenotypes were used. The results showed an increase in the variances explained by the autosomal markers for all traits when the X chromosome was not included. For SC, there was an increase of more than 10% for the windows on chromosomes 2 and 6. For P16, the effect was increased by almost 20% for windows on chromosome 5. The same pattern was found for AFC, with an increase of more than 10% for the most important windows. The results indicate that the noninclusion of the X chromosome can overestimate the effects of autosomes on SC, P16 and AFC not only because of the additive effect of the X chromosome itself but also because of its epistatic effect on autosomal genes.  相似文献   
40.
Home monitoring of blood glucose (HMBG) concentrations has been recommended in the monitoring of human diabetics for 3 decades. During the last number of years, it also gained popularity in long-term follow-up of diabetic cats and dogs. The aim of this retrospective study was to evaluate the practical feasibility of and identify the major problems encountered with HMBG in diabetic pets. A standard questionnaire was filled in by owners of 9 diabetic pets monitored with HMBG. The need for more than 1 puncture to obtain a blood drop, the creation of a sufficient blood drop, the need for assistance in restraining the pet, and the resistance of the pet were the most frequently encountered problems during HMBG. The major obstacles for the owners to start with HMBG were also identified. In conclusion, HMBG is a practical and simple technique for most owners and, overall, owners were satisfied.  相似文献   
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