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81.
A possible role of breeding activities in the composition of the microbial population in stallions' external genitalia (EG) and the relationship between micro‐organisms colonizing the skin of the abdomen and the ones colonizing the EG have not been studied. In experiment 1, EG microbiological samples were collected from 41 stallions used for both natural cover and semen collection (BST) and from 18 non‐breeding stallions (NBST). A higher (p < 0.05) frequency of isolation of potentially pathogenic species was found for BST. Age did not influence number of micro‐organism species isolated both in BST and NBST. In experiment 2, the microbial content of the EG and semen was compared in 23 BST. Most micro‐organisms isolated from the EG were present in semen, albeit with a numerically lower prevalence. In 7 stallions, six microbial species isolated from semen were absent from the EG cultures, suggesting contamination by the operator. In experiment 3, a numerically higher number of micro‐organism species was isolated from the EG of 31 stallions, than from their skin of the ventral abdomen in contact with the penis or from the skin of the thorax. With the sole exception of Escherichia coli, potentially pathogenic bacteria were only isolated from the EG but not from the skin. Results suggest that breeding activity increased the number of species colonizing the EG; most species isolated from the EG were also found in semen even if with a lower frequency, and additional semen contamination seemed to occur during its manipulation. Many micro‐organism species of the skin were also isolated from the penis, but independently of being or not in contact with the penis, skin did not seem to provide an adequate environment for the growth of potentially pathogenic bacteria that were isolated from EG, with the sole exception for E. coli.  相似文献   
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83.
ObservationsA 9 year-old, 40 kg, female spayed Bouvier des Flandres was anesthetized for surgical removal of an intra-cardiac mass. Pre-anesthetic work-up included thoracic radiographs, which revealed moderate pleural effusion, and cardiac ultrasound, which identified a mass attached to the wall of the right ventricular outflow tract (RVOT). The mass caused dynamic obstruction of the RVOT during systole. The dog was pre-medicated with intravenous (IV) hydromorphone (0.05 mg kg?1). Following pre-oxygenation, anesthesia was induced with ketamine (3.75 mg kg?1, IV) and diazepam (0.18 mg kg?1, IV). Anesthesia was maintained with isoflurane in oxygen, an intravenous constant rate infusion (CRI) of fentanyl (10–30 μg kg?1 hour?1) and a CRI of lidocaine (50–200 μg kg?1 minute?1). A right lateral thoracotomy was performed. The heart was stopped transiently with a cold cardioplegic solution for 7.83 minutes to allow the removal of the mass through an open-heart procedure. No cardiopulmonary bypass was used. The heart was successfully restarted after cardiopulmonary resuscitation with internal cardiac massage and internal defibrillation. The dog recovered uneventfully from anesthesia without any apparent neurological sequelae. Post-operative analgesia consisted of intercostal nerve blocks with bupivacaine, CRIs of fentanyl (2–5 μg kg?1 hour?1) and lidocaine (40 μg kg?1 minute?1) and with oral meloxicam (0.1 mg kg?1). Five days following surgery, the dog was discharged from the hospital. Histopathology and immunohistochemistry of the mass identified an ectopic thyroid carcinoma.ConclusionsThis case showed the feasibility of whole body hypothermia and using a cold cardioplegic solution to induce cardiac arrest for a short open-heart procedure.  相似文献   
84.
Between 1999 and 2002, the effect of mid-season doramectin treatments on the level of resistance in pyrethroid-resistant horn fly populations was examined at three separate Louisiana State University Agricultural Center research stations. The cattle were treated with pyrethroid ear tags in all years at all farms, and each farm received a mid-season doramectin treatment in 1 year. The number of weeks of control at Red River was 11 weeks higher in the year following the mid-season treatment of doramectin. At Macon Ridge, the number of weeks of control was 2 weeks higher in the year following the doramectin treatment. No change was observed at St. Joseph. The LC50s for fly populations tested at Macon Ridge and St. Joseph were found to increase for pyrethroids from the spring populations to the fall populations between 2000 and 2002. The LC50s for fly populations at Red River followed the same trends except in 2000, the year when the doramectin treatment was administered. Flies collected pre and post-treatment each year from St. Joseph and Red River were assayed for two alleles (kdr and skdr) associated with target site resistance to pyrethroids. Flies collected pretreatment at Macon Ridge in 1999 also were assayed for the kdr and skdr, and this population of flies had a frequency of 85.6% R-kdr alleles. At St. Joseph and Red River there was a general decline in the frequency of homozygous susceptible skdr (SS-skdr) and homozygous susceptible kdr (SS-kdr) individuals, as well as a general increase in homozygous resistant skdr (RR-skdr) and homozygous resistant kdr (RR-kdr) individuals, during the 4-year study. At both sites, the frequency of R-kdr alleles increased significantly in flies collected in the fall compared to flies collected in the spring with the exception of Red River in 2000, when dormacetin was applied. The frequency of the R-kdr alleles was significantly higher in flies collected in the fall compared to flies collected in the spring in the following year at both sites in two out of three comparisons. The frequency of R-skdr alleles was significantly lower in fly populations tested in the spring compared to fly populations tested in the fall at both farms in years when doramectin was not applied but there were no differences in the years when doramectin was applied. The frequency of R-skdr alleles was significantly higher in fly populations tested in the fall compared to in the spring the following year during all three comparisons at Red River and in one of three comparisons at St. Joseph.  相似文献   
85.
Rabbits were immunized with inactivated influenza virus via the subarachnoidal (SA) or subcutaneous (SC) route, and the antibody titers in cerebrospinal fluid (CSF) and serum were assayed. There were no nervous signs or morphological lesions related to SA immunization. In the SC group, the antibody titer was elevated in serum, but not elevated in CSF. In the SA group, the antibody titer was significantly elevated in serum and even in CSF, and their antibody titers were much greater than in the SC group. The present results suggest that intrathecal immunization is more effective than SC immunization at inducing a protective immune response against the transneural spread of viruses.  相似文献   
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87.
A novel technique was developed to estimate the caudal medial tibial plateau landmark in the face of osteophytosis to improve accuracy in tibial plateau angle measurements. Using this technique, tibial plateau angles were evaluated in 31 normal dogs before and 8 months after right cranial cruciate ligament transection. There was no significant difference in mean tibial plateau angle before or after induction of osteophytosis. Additionally, it was determined that 90% of dogs had a difference of =2 degrees between right and left tibial plateau angles, which was considered symmetrical.  相似文献   
88.
Melatonin, the major secretory product of the pineal gland, scavenges a variety of reactive oxygen and nitrogen species in vivo and in vitro, indicating that melatonin is a potent function as an antioxidant. The objective of this study was to investigate the effect of melatonin in the presence or absence of hydrogen peroxide (H2O2) on sperm characteristics (motility, viability, survival rate, membrane integrity, lipid peroxidation (LPO) and mitochondria activity) and also to examine the developmental rates to the blastocysts stage of porcine oocytes fertilized in vitro with semen treated with or without melatonin (100 nm ) in the presence or absence of H2O2 (250 μm ). The sperm were treated with melatonin in the presence or absence of H2O2 for 3, 6, 9 and 12 h at 37°C and then analysed for the sperm characteristics. The porcine embryos were produced by in vitro maturation and in vitro fertilization (IVM/IVF) using semen treated with or without melatonin (100 nm ) in the presence or absence of H2O2 (250 μm ) for 6 h. The semen characteristics, including motility, viability, survival rate, membrane integrity and mitochondria activity, were higher in the groups that were treated with melatonin in comparison to other groups, irrespective of incubation periods. Malondialdehyde levels in control, melatonin and melatonin + H2O2 groups were lower than H2O2 only group. A positive correlation was shown among motility, viability, survival rate and membrane integrity, but a negative correlation was observed between LPO and the other evaluation methods. The developmental rates to blastocysts of IVM/IVF porcine oocytes fertilized by semen treated with melatonin were significantly increased compared with any other groups, with the cell number of blastocysts shown to have a similar trend to the developmental rates. These results demonstrate that melatonin can improve the semen characteristics during in vitro storage and support the developmental ability of IVM/IVF embryos in pigs.  相似文献   
89.
This study investigated the effect of dietary nutmeg oil (NO) on growth performance, blood parameters, lipid peroxidation and heat shock protein (HSP) 70 expression in Korean native chicken (KNC) reared under hot temperature. We allocated 273 meat‐type KNCs (Hanhyup3, 4‐week‐old, body weight [BW] = 539.93 ± 1.75 g) to the following three treatments with seven replicate pens (13 birds/pen) per treatment. Three treatment diets were as follows: (a) Control, basal diet without NO supplementation; (b) NO 250; and (c) NO 500, basal diet supplemented with 250 and 500 ppm NO respectively. Diets and water were provided ad libitum throughout the 6‐week feeding trial. During overall period (0–6 weeks), no differences (p > 0.05) were observed in BW gain (BWG), feed intake (FI) and feed conversion rate (FCR) among treatments. However, the FI at 0–3 weeks decreased (p < 0.05) quadratically with increasing NO levels. Most blood parameters did not differ (p > 0.05) among treatments, although the monocyte level of the NO 500 group was considerably lower (p > 0.05) than that of the other groups. Furthermore, dietary NO did not affect serum triglyceride, cholesterol, total protein, albumin, calcium, phosphorus and alanine aminotransferase (ALT) levels (p > 0.05); however, it linearly decreased serum aspartate aminotransferase (AST) level (p < 0.05). Additionally, serum malondialdehyde (MDA) concentration decreased (p < 0.05) and heart MDA concentration was lower (p = 0.08) with increasing dietary NO supplementation. After a 3‐hr heat (35°C) challenge, the rectal temperature (RT) reduced (p < 0.05) linearly with increasing NO levels. Dietary NO did not affect liver HSP70 (p > 0.05) gene expression. In conclusion, NO potentially enhanced the ability of chickens to alleviate heat stress. Furthermore, our findings suggest that lipid oxidation inhibition by dietary NO likely mediated the enhanced heat‐stress tolerance of the chickens.  相似文献   
90.
A two‐year‐old Rottweiler presented for acute onset of a right hindlimb lameness 20 weeks after a cementless total hip replacement (THR) and 16 weeks after open reduction to address luxation of the THR. Radiographs revealed periosteal proliferation of the medial acetabulum and a stable implant. Synovial fluid cytology was consistent with inflammatory joint fluid. Treatment consisted of surgical debridement and intravenous and oral antibiotics. THR implants were not removed. Culture of tissue removed from the THR site yielded growth of Pseudomonas and Staphylococcus species. Lameness resolved 2 months after surgery. Twenty months after surgery, the dog was exercising normally with no clinical lameness and pelvic radiographs revealed no evidence of implant loosening and markedly decreased periosteal reaction. To the authors’ knowledge, this is the first report of an infected THR site successfully treated without prosthesis explantation in the dog.  相似文献   
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