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91.
Hypoxic ascites in broilers: a review of several studies done in Colombia   总被引:2,自引:0,他引:2  
A Hernandez 《Avian diseases》1987,31(3):658-661
In Bogotá, Colombia, broilers developed ascites due to pulmonary hypertension of hypoxic origin at 2638 m above sea level. This disease has tremendous economic impact in various countries of the world and is characterized by pulmonary hypertension, hypertrophy and hyperplasia of the right ventricle of the heart, increased hematocrit and hemoglobin values, and ascites. This entity appears to be influenced by management practices and by inability of broilers to adapt to high altitude.  相似文献   
92.
Prevalence of infectious diseases in feral cats in Northern Florida   总被引:7,自引:0,他引:7  
Objectives of this study were to determine prevalence of infection in feral cats in Northern Florida with a select group of infectious organisms and to determine risk factors for infection. Blood samples or sera from 553 cats were tested with a panel of antibody, antigen or PCR assays. Male cats were at higher risk for FIV, Mycoplasma haemofelis, and M. haemominutum. Infection with either FeLV or FIV was associated with increased risk for coinfection with the other retrovirus, M. haemofelis, or M. haemominutum. Bartonella henselae had the highest prevalence and was the only organism that did not have any associated risk for coinfection with other organisms. Feral cats in this study had similar or lower prevalence rates of infections than those published for pet cats in the United States. Thus, feral cats assessed in this study appear to be of no greater risk to human beings or other cats than pet cats.  相似文献   
93.
OBJECTIVE: To evaluate horseshoe characteristics and high-speed exercise history as risk factors for catastrophic musculoskeletal injury in Thoroughbred racehorses. ANIMALS: 377 horses (37,529 race starts). PROCEDURES: Shoe characteristics included material, toe grab height, heel traction device, pads, and rim shoes. Racing variables were obtained from a computerized database. Forty-three horses that had a musculoskeletal injury and then failed to race or train for 6 months (cases) and 334 noninjured horses from the same race in which a horse was injured (controls) were compared regarding risk factors. RESULTS: Overall, 98% of race starts were associated with aluminum shoes, 85% with toe grabs, 32% with pads, and 12% with rims on forelimb horseshoes. Among 43 horses with musculoskeletal injury, sex (geldings), an extended interval since last race, and reduced exercise during the 30 or 60 days preceding injury were risk factors for catastrophic injury. Odds of injury in racehorses with toe grabs on front shoes were 1.5 times the odds of injury in horses without toe grabs, but this association was not significant (95% confidence interval, 0.5 to 4.1). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that horses that return to racing after an extended period of reduced exercise are at high risk of catastrophic musculoskeletal injury. Results regarding the use of toe grabs as a possible risk factor for catastrophic injury were inconclusive because the probability of declaring (in error) that use of toe grabs was associated with an increased risk of musculoskeletal injury (eg, odds ratio > 1.0) was 38%.  相似文献   
94.
(1) In order to make trimethoprim (TMP) available to broilers throughout the day, a sustained release formulation (SRF) of the drug in the form of granules was added to the water tank that supplies drinking water. (2) Broilers were initially dosed with sulphachloropiridazine-TMP (SCP-TMP 5:1) and then further medicated throughout the day, achieving in the end a dose of 30 mg/kg each of SCP and TMP (group A). Group B received a preparation with the same dose of SCP and TMP (1:1) as group A, but administered as a single dose without the SRF of TMP. Group C received the customary SCP-TMP 5:1 preparation (30 and 6 mg/kg, respectively). Water tanks were completely consumed in 3 to 4 h. (3) Broilers were bled at different times and concentration of antibacterial activity in serum determined by correlating the composite antibacterial activity of SCP and TMP with actual concentrations of these drugs by means of a microbiological agar diffusion assay. (4) Time vs serum concentrations of activity were higher in group B; the increments in the maximum serum concentration for group B over groups A and C being 39 and 67%, respectively. (5) However, the sustained concentration of activity over time, measured as the area under the cu)rve, was highest in group A. Group B had higher values for area under the curve than group C. (6) An additional dose of TMP to achieve 30 mg/kg of both SCP and TMP improves the serum concentration of this combination over the customary 5:1 proportion. The best values for sustaining antibacterial activity were obtained using a 1:1 ratio as in group A. The use of a SRF as in group A may translate into better clinical results.  相似文献   
95.
The pharmacokinetics of amoxicillin (Amx) were determined in pigs following intravenous (IV) administration of a single dose of 15 mg/kg and a single dose of 15 mg/kg of a new oral formulation (Amx-FP containing 10% amoxicillin). Residue studies were performed to determine residues in edible tissues of healthy pigs after chronic oral administration of Amx-FP at a daily dose of 15 mg/kg for five consecutive days. After IV administration, the plasma concentration was characteristic of a two-compartment open model. The main pharmacokinetic variables were: t(1/2lambda(n)), MRT=90.1 min, V(darea)=0.81 L/kg and Cl(b)=3.9 mL/kg/min. After single oral administration the main pharmacokinetic variables were: C(max)=758 mug/L, t(max)=347 min and Cl(b/f)=3.7 mL/kg/min for Amx-FP. The oral bioavailability (F) was calculated at 11% for Amx-FP. Based on maximum residue levels (MRL) for AMX in pigs established at 50 microg/kg for all tissues, the withdrawal times of AMX in muscle and skin plus fat were estimated (95% tolerance limit and 95% confidence) to fall below the MRL after a withdrawal period of seven days. Levels of AMX in the liver and kidneys were estimated to fall below the MRL after a withdrawal period of four days.  相似文献   
96.
Osteoarthritis of the metacarpophalangeal joint is common cause of lameness in equine athletes, and is hallmarked by articular cartilage damage. An accurate, noninvasive method for measuring cartilage thickness would be beneficial to screen for cartilage injury and allow for prompt initiation of interventional therapy. The objective of this methods comparison study was to compare computed tomographic arthrography (CTA), magnetic resonance imaging (MRI), and magnetic resonance arthrography (MRA) measurements of articular cartilage thickness with gross measurements in the metacarpophalangeal joint of Thoroughbred horses. Fourteen cadaveric, equine thoracic limbs were included. Limbs were excluded from the study if pathology of the metacarpophalangeal articular cartilage was observed with any imaging modality. Articular cartilage thickness was measured in nine regions of the third metacarpal bone and proximal phalanx on sagittal plane MRI sequences. After intra‐articular contrast administration, the measurements were repeated on sagittal plane MRA and sagittal CTA reformations. In an effort to increase cartilage conspicuity, the volume of intra‐articular contrast was increased from 14.5 ml, to maximal distention for the second set of seven limbs. Mean and standard deviation values were calculated, and linear regression analysis was used to determine correlations between gross and imaging measurements of cartilage thickness. This study failed to identify one imaging test that consistently yielded measurements correlating with gross cartilage thickness. Even with the use of intra‐articular contrast, cartilage surfaces were difficult to differentiate in regions where the cartilage surfaces of the proximal phalanx and third metacarpal bone were in close contact with each other.  相似文献   
97.
Myeloperoxidase (MPO) is a pro‐oxidant enzyme associated with decreased motility in thawed equine semen. This study aimed to describe MPO concentration, activity and subunits in raw and thawed semen and to correlate these data with motilities in raw and thawed semen. Semen samples from five stallions were collected four times. Motilities were assessed in raw and thawed semen. MPO assays were performed in raw seminal plasma, raw sperm‐rich pellet and thawed semen. Total and active MPO concentrations were, respectively, assayed by enzyme‐linked immunosorbent assay and specific immunological extraction followed by enzymatic detection. MPO subunits present in semen were characterized by Western blot. Purified active MPO was added in saline solution and freezing extender to control its activity during freezing procedure. Differences between medians were determined using Kruskal–Wallis test, and correlations were determined using Spearman's test for nonparametric data. Active MPO concentration was low in seminal plasma and thawed semen, but high in pellet (p = 0.0058), as the opposite relation was observed for total MPO concentration (p < 0.0001). In seminal plasma and post‐thaw semen, inactive 86‐kDa MPO precursor was mainly observed. Purified MPO activity was decreased in the extender (p = 0.0286). MPO activity in pellet was highly correlated with thawed progressive motility (r = ?0.5576, p = 0.0086). Inactive MPO precursor and unknown low molecular weight inactive MPO precursor subunits explain low MPO activity in semen. Major MPO activity was observed in pellet, and post‐thaw loss of activity is partially explained by MPO inactivation in extender. Thawed semen motility was negatively correlated with MPO activity in pellet, becoming a potential freezability predictor.  相似文献   
98.
The changes in the nonanthocyanin phenolic composition during red wine malolactic fermentation carried out spontaneously and by four different starter cultures of the species Oenococcus oeni and Lactobacillus plantarum were examined to determine whether differences in nonanthocyanin polyphenolic compounds could be attributed to the lactic acid bacteria (LAB) strain that performs this important step of the wine-making process. The polyphenolic compounds were analyzed by high-performance liquid chromatography with photodiode array detection and HPLC with electrospray ionization-mass spectrometry detection. The malolactic cultures selected for this study were indigenous wine LAB strains from the A.O.C. Rioja (Spain). Results showed different malolactic behaviors in relation to wine phenolic compositions for O. oeni and L. plantarum, and also, a diversity was found within each group. The hydroxycinnamic acids and their derivatives, the flavonols and their glycosides, the flavanol monomers and oligomers, and trans-resveratrol and its glucoside were the main compounds modified by the different LAB. The wild LAB population exerted a greater impact in the wine content of some of these phenolic compounds than the inoculated selected monocultures of this study.  相似文献   
99.
Pen housing has been proposed in rabbits as an alternative to standard-sized cages. Rabbits reared in pens show greater physical activity. This study investigated whether jump exercise could modify body composition, muscle biochemical and histological characteristics, and some meat quality traits, including the biomechanical properties of tendons. Male weaned rabbits of similar BW (793 +/- 11 g) were either reared in giant collective cages and had to jump over obstacles to get food and water for 35 consecutive days (EXE), or confined in small isolated cages (SEDN). Rabbits were weighed weekly to determine ADG (n = 79 EXE; n = 46 SEDN) and ADFI (n = 9 cages in EXE; n = 46 cages in SEDN). At approximately 10 wk of age, rabbits were slaughtered in 2 series. After overnight chilling, carcasses in the first series (n = 30 EXE; n = 27 SEDN) were divided into fore, intermediate, and hind parts. Color and ultimate pH were recorded in the biceps femoris (BF) and LM. The Achilles tendon and patellar ligament were dissected from the legs and cooked. Muscles [semimembranosus proprius, semimembranosus accessorius (SMA), and BF] were harvested from the legs in a subset of animals from the second series (n = 10 in EXE; n = 9 in SEDN). Both ADG and ADFI were slightly reduced (P < 0.10) in EXE rabbits compared with SEDN rabbits. Exercised rabbits showed a greater (P = 0.01) proportion of hind parts than SEDN rabbits. Enzyme activities of 3-hydroxyacyl-CoA dehydrogenase and citrate synthase, which play key roles in fatty acid oxidation and the terminal oxidative degradation of nutrients, respectively, were increased in the semimembranosus proprius, SMA (except citrate synthase), and BF muscles of EXE rabbits compared with SEDN rabbits. Only SMA exhibited a decreased (P = 0.05) activity of the glycolytic enzyme, lactate dehydrogenase, in EXE rabbits compared with SEDN animals. Total lipid content, mean diameter of perimysial adipocytes, and activities of core lipogenic enzymes in the SMA and BF muscles did not differ between EXE and SEDN rabbits. Meat color in BF was shifted toward greater a* (red; P = 0.001) and b* (yellow; P = 0.02) values in EXE rabbits compared with SEDN rabbits. Cooked Achilles tendon and patellar ligaments in the legs had greater stiffness (P < or = 0.05) in EXE rabbits compared with SEDN rabbits. This experiment demonstrates that rabbit muscles turn to a more oxidative metabolic pattern in response to jump exercise. The quality of attachment of cooked meat to bone is also improved in active rabbits.  相似文献   
100.
The effect of over‐expression in tobacco plants of cytosolic Cu,Zn‐superoxide dismutase (cytsod) and ascorbate peroxidase (cytapx) alone, or in combination, against bacterial wildfire and crown gall diseases, caused by Pseudomonas syringae pv. tabaci and Agrobacterium tumefaciens, respectively, was investigated. Disease tolerance was observed in all the transgenic lines against the two causal agents, with various levels of resistance, with the double transformants (lines 35 and 39) the most resistant against bacterial wild fire. In the case of P. syringae pv. tabaci, disease tolerance and symptom decrease was associated with a lower bacterial population and a higher level of several antioxidant defence enzymes. Transgenic lines also exhibited an enhanced tolerance against A. tumefaciens, with the transgenic line harbouring cytapx (line 51) the most resistant to crown gall disease. However, this was only observed with strain C58 among the three pathogenic strains tested. These results suggest that cytosolic antioxidant defences have a role in increasing tolerance to the oxidative stress caused by some bacterial pathogens, and resistance of these tobacco lines to wildfire disease seems to be independent of tissue necrosis.  相似文献   
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