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951.
Hatkin J  Styer E  Miller D 《Avian diseases》2002,46(4):1070-1075
A 4.5-yr-old rooster was presented for a "lump on the neck." The bird exhibited dyspnea immediately prior to death. Necropsy revealed a crateriform lesion in the crop. Histologically, the lesion was diagnosed as an invasive squamous cell carcinoma, extending almost the entire thickness of the crop. Polymerase chain reaction and ultrastructural examination failed to identify a viral component. Early vascular invasion was identified.  相似文献   
952.
Birth and rearing conditions were evaluated for their effects on pig growth, body composition, and pork quality using 48 barrows during the spring and summer months. Pigs were either farrowed in indoor crates or outdoor huts. At weaning, indoor-born and outdoor-born pigs were randomly allotted to indoor or outdoor treatments for growing/finishing. Body weight data were collected. Pigs were transported 5 h to a commercial processing plant, allowed 2 h of rest, and then processed as a group under commercial conditions. Boneless loins were collected from the left side of each carcass and aged for 14 d. Objective and subjective color measurements were taken on the longissimus muscle at the 10th rib on d 14 postmortem. Loin chops were evaluated for sensory attributes, shear force, and retail display features. Pigs born outdoors were heavier and had greater ADG at all growth intervals after weaning (d 28, 56, 112, and final weight, P < 0. 05) than pigs born indoors. Outdoor-born pigs had heavier carcass weights (91.2 vs 81.3+/-3.4 kg, P < 0.001), larger loineye areas (54.6 vs 49.7+/-0.2 cm , P < 0.05), and higher pork flavor intensity scores (6.5 vs 6.1+/-0.10, P < 0.01) than indoor-born pigs. Birth x rearing environment interactions were not significant for most measures. Backfat measurements at the last rib were greater (3.2 vs 2.8+/-0.05 cm, P < 0.05) for the pigs reared outdoors than for the pigs reared indoors. Pigs finished outdoors had more reddish pink color scores, lower shear force values, and lower L* values, indicating darker-colored pork, compared with pigs finished indoors (P < 0.05). Pig birth environment played a significant role in improving growth rates of outdoor-born pigs and increasing pork flavor intensity scores of loin chops from pigs born outdoors. Finishing pigs outdoors may improve pork color and tenderness but also may increase backfat thickness when they are fed conventional diets.  相似文献   
953.
Effects of pig birth (first 3-wk period) and rearing environments on growth and muscle quality characteristics of loins were evaluated in three experiments over seasons in west Texas and central Missouri. Housing systems included indoor slatted-floor buildings, indoor deep-bedded buildings, outdoor housing on dirt, and outdoor housing on alfalfa pasture. Experiments were conducted during the growing/finishing phases and pigs were slaughtered at the same age. Loins were collected, vacuum-packaged, and stored for 14 d at 2 degrees C. Pigs born and finished in an outdoor environment during the summer months (Exp. 1) had a greater ADG (0.92 vs 0.82+/-0.06 kg/d, P < 0.05) and had heavier carcass weights (87.9 vs 78.4+/-2.4 kg, P < 0.05) than pigs born and finished in an indoor environment with a slatted-floor finishing building. Carcasses from the outdoor-reared group measured a larger (P < 0.05) loineye area and were fatter (P < 0.01) at the first rib, last rib, and last lumbar vertebra measurements than carcasses from the indoor-reared group. Loin chops from outdoor-reared pigs had darker color scores in the retail display case throughout the 4-d period, measured lower L* values on d 1, and had more discoloration and browning on d 4 than loin chops from the indoor-reared group. During the winter months (Exp. 2), no difference was detected in ADG, carcass measurements, sensory characteristics, or shear force values from indoor-born pigs placed in either an outdoor or indoor finishing environment. Pigs finished on deep bedding (Exp. 3) had heavier carcass weights and more backfat (P < 0.01) than pigs finished on slats, but no differences were detected in sensory panel or shear force results. Overall, carcass measurements, pH, drip loss, sensory panel, and shear force values were similar among the groups finished in different housing systems. Outdoor or deep-bedded systems may increase growth rates of pigs if suitable land area and resources are available, but pork quality of loins will be similar for pigs finished in either conventional or alternative systems.  相似文献   
954.
Semen was collected from three captive odontocetes: a killer whale (Orcinus orca); a Pacific white-sided dolphin (Lagenorhynchus obliquidens) and a beluga (Delphinapterus leucas). Semen was collected from the killer whale and Pacific white-sided dolphin using behavioural commands, whereas semen from the beluga was collected postmortem. Ultrastructure of the spermatozoa was examined using scanning and transmission electron microscopy. Species differences were more pronounced in the head sections followed by the midpiece and finally, the tail sections. Spermatozoa from the killer whale and beluga were similar but differed from the Pacific white-sided dolphin spermatozoa.  相似文献   
955.
Canines affected with corneal lesions demonstrate increased proteolytic activity at the affected site. Canines that develop persistent corneal ulcers and maintain elevated levels of proteolytic activity respond to protease inhibitor therapy with polysulpated glycosaminoglycan, PSGAG. In this study, the proteolytic activity expressed in lacrimal fluid of canines was evaluated as normal (1.15 U mL−1) or healed (1.19 U mL−1). Six of the 26 dogs affected with persistent corneal ulcers, however, had a protease level consistent with the unaffected control animals. These dogs did not appear to respond to PSGAG therapy. Two pathophysiologies for persistent corneal ulcers are indicated. Identifying which mode is active could help determine the therapeutic treatment needed.  相似文献   
956.
Cardiovascular, pulmonary and anaesthetic-analgesic responses were evaluated in 18 male and female dogs to determine the effect of the injectable anaesthetic propofol used in conjuction with acepromazine and butorphanol. The dogs were randomly divided into three groups. Dogs in Group A were premeditated with 0.1 mg/kg of intramuscular acepromazine followed by an induction dose of 4.4 mg/kg of intravenous propofol; Group B received 0.2 mg/kg of intramuscular butorphanol and 4.4 mg/kg of intravenous propofol; dogs in Group AB were administered a premeditation combination of 0.1 mg/kg of intramuscular acepromazine and 0.2 mg/kg of intramuscular butorphanol, followed by induction with 3.3 mg/kg of intravenous propofol. The induction dose of propofol was given over a period of 30-60 seconds to determine responses and duration of anaesthesia. Observations recorded in the dogs included heart and respiratory rates, indirect arterial blood pressures (systolic, diastolic and mean), cardiac rhythm, end-tidal CO, tension, oxygen saturation, induction time, duration of anaesthesia, recovery time and adverse reactions. The depth of anaesthesia was assessed by the response to mechanical noxious stimuli (tail clamping), the degree of muscle relaxation and the strength of reflexes. Significant respiratory depression was seen after propofol induction in both groups receiving butorphanol with or without acepromazine. The incidence of apnea was 4/6 dogs in Group B, and 5/6 dogs in Group AB. The incidence of apnea was also correlated to the rate of propofol administration. Propofol-mediated decreases in arterial blood pressure were observed in all three groups. Moderate bradycardia (minimum value > 55 beats/min) was observed in both Groups B and AB. There were no cardiac dysrhythmias noted in any of the 18 dogs. The anaesthetic duration and recovery times were longer in dogs premeditated with acepromazine/butorphanol.  相似文献   
957.
Fluoresceinated, heat-aggregated bovine immunoglobulins (B-IgG) and human immunoglobulins (H-IgG) were used to detect a receptor for the crystallizable fragment (Fc) of the immunoglobulin molecule on peripheral blood lymphocytes (PBL) of cattle. The aggregated and B-IgG and H-IgG bound to the bovine PBL, but aggregated H-IgG was found to be more sensitive for the detection of Fc receptors. The specificity of aggregated H-IgG binding to the Fc receptors was established by demonstrating that antigen-antibody complexes inhibited this binding, and unaggregated H-IgG did not bind significantly to PBL. Double-labeling experiments suggested that all Fc+ cells have surface immunoglobulins (SIg), a marker for B lymphocytes. The percentage of Fc+ and SIg+ cells in normal animals was 9.5% (range 4-15%) and 16.2% (range 4.5-30.2%), respectively. Persistent lymphocytotic cows had 2.71 times more Fc+ and 3.85 times more SIg+ lymphocytes than did normal cows. Cows with lymphosarcoma had a lower percentage of Fc+ and SIg+ cells than did cows with persistent lymphocytosis. Cases with thymic lymphosarcoma and those with the skin form of leukemia had normal percentages of Fc+ and SIg+ cells.  相似文献   
958.
An endobronchial polyp was visible radiographically and bronchoscopically in an 11-year-old, mixed-breed dog with a persistent cough. The polyp was removed by traction. Initial histological examination suggested it was a myxomatous fibroma. The cough resolved but recurred with polyp regrowth. Two additional lung masses became visible radiographically. The polyp was removed twice more at 6-month intervals. Euthanasia was performed 15 months after first presentation when coughing recurred soon after the final bronchoscopy. Histological examination revealed that the mass was a myxomatous sarcoma. The lung contained two other unrelated tumors: a bronchioloalveolar carcinoma and a carcinoma of unknown origin.  相似文献   
959.
In the present study we have employed an in vitro organ challenge model to study the post-challenge responses in parasite na?ve and immune gastric tissue of sheep, in an attempt to identify the host derived factors involved in immune exclusion of Teladorsagia circumcincta larvae. Proteins present in the epithelial cells and mucus from ovine abomasa following parasite challenge in previously na?ve and immune animals were analysed through Matrix Assisted Laser Desorption/Ionization-Time of Flight (MALDI-Tof)-MS and shotgun proteomics. MALDI-ToF analysis of epithelial cell lysates revealed that a number of proteins identified were differentially expressed in na?ve and immune cells. These included intelectin and lysozymes, which were present at higher levels in epithelial cell lysates derived from immune samples. A large number of proteins were identified in the mucosal wash from immune tissue which were not present in the mucosal wash of the na?ve tissue. Some of these proteins were present in washes of immune tissue prior to the parasite challenge including immunoglobulin A, galectin 14 and 15 and sheep mast cell protease 1. However, other proteins, such as calcium activated chloride channel and intelectin were only detected in the washings from the challenged tissue. The latter may be related to an enhanced mucus release, which may result in entrapment of infective larvae and thus reduced establishment in tissue that has been previously challenged with the parasite. In conclusion, several proteins have been identified which may be involved, either directly or indirectly, in the exclusion and immune elimination of incoming infective larvae. In the present study, the usefulness of the in vitro model has been confirmed, and the global proteomic approach has identified proteins that had not previously been associated with parasite exclusion from abomasal mucosa, such as the calcium activated chloride channel.  相似文献   
960.
The objective of this retrospective article was to describe the use of, and to determine long-term outcome of, tibiotarsal arthroscopy in dogs. The medical records of 20 client-owned dogs with tibiotarsal joint disease with arthroscopic treatment were reviewed. Long-term follow-up evaluation of lameness, force plate gait analysis, and radiographs to assess progression of degenerative joint disease (DJD) were performed. Arthroscopy was utilized in the diagnosis of talar osteochondritis dissecans (OCD), collateral ligament injury, septic arthritis, immune mediated arthritis, and a distal talar fragment. Sixteen joints with OCD treated resulted in 10/14 dogs with lameness after exercise only, progression of DJD in most cases, and chronic lameness when comparing operated to unoperated limbs with force plate evaluation at a mean follow-up of 35 months. Following treatment, three dogs with collateral ligament injury had reduced weight bearing on the operated limb, radiographic progression of DJD, and minimal lameness at a mean follow-up of 27 months. Tibiotarsal arthroscopy can be successfully used to help diagnose, and often to treat: OCD, collateral ligament injury, fractures, septic and non-septic arthritis in the dog. The minimally invasive nature of arthroscopy preserved joint stability while allowing complete examination of the articular cartilage. In most cases long term tibiotarsal DJD advancement was the rule.  相似文献   
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