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1.
Joyce D'SILVA 《Integrative zoology》2006,1(1):53-58
Industrial animal agriculture is grounded in the concept of maximizing productivity and profit. Selective breeding for maximum productivity in one characteristic of the animal (e.g. milk yield in cows, or breast meat in broiler chickens) has resulted in genotypes and phenotypes that may predispose the animals to poor health and welfare. The conditions in which these individuals are kept may also frustrate many inherited behaviors that they are strongly motivated to perform. In order to curb the resulting harmful aberrant behaviors, such as feather‐pecking in chickens, we sometimes resort to mutilating the animals. In many places chickens are routinely de‐beaked by means of a hot metal guillotine. Compassion in World Farming (an international organization that promotes the humane treatment of farm animals) believes that it is unethical to treat sentient beings in such ways. We have a duty to respect farm animals' sentience by providing them with housing conditions that take their needs and wants into account, and by reverting to the use of dual‐purpose, slower‐growing breeds that have the potential for good welfare. Alternatives to current farming practices are available, and we owe it to the animals, and to our consciences, to pursue them. 相似文献
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Mohammadreza Ebrahimi Laura Mara Bernardo Chessa Fabrizio Chessa Abbas Parham Maria Dattena 《Reproduction in domestic animals》2021,56(3):467-475
Microinjection of exogenous DNA into the cytoplasm of matured oocytes or zygotes is a promising technique to generate transgenic animals. However, the data about the microinjection time and procedure in sheep are limited and have not treated in detail. To obtain more in-depth information, the Sarda sheep oocytes from abattoir-derived ovaries were subjected to IVM and IVF. Then, the GFP plasmid as a reporter gene was injected into the cytoplasm of MII oocytes (n: 95) and zygotes at different post-insemination intervals (6–8 hpi, n: 120; 8–10 hpi, n: 122; 10–12 hpi, n: 110 and 12–14 hpi, n: 96). There were no significant differences in the cleavage rates between the groups. However, blastocyst rate of injected zygotes at all-time intervals was significantly lower than injected MII oocytes and control group (p < 0.05). Interestingly, the proportion of GFP-positive embryos was higher at 8–10 hpi compared with other injected groups (4 % versus 0 %, p < 0.01). Among these, the proportion of mosaic embryos was high and two of those embryos developed to the blastocyst stage. In conclusion, we settled on the cytoplasmic microinjection of GFP plasmid at 8–10 hpi as an optimized time point for the production of transgenic sheep and subsequent experiments. 相似文献
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Alana Batista dos Santos Mara Lúcia Albuquerque Pereira Herymá Giovane de Oliveira Silva Gleidson Giordano Pinto de Carvalho Taiala Cristina de Jesus Pereira Leandro Sampaio Oliveira Ribeiro José Augusto Gomes Azevêdo Maria das Graças Conceição Parada Costa Silva Larisse Borges Sousa Leandro Borges Sousa Daiane de Oliveira Alencar 《Tropical animal health and production》2016,48(3):509-515
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Plasma Adrenocorticotropin Concentration in Healthy Horses and in Horses With Clinical Signs of Hyperadrenocorticism 总被引:2,自引:0,他引:2
Laurent Couëtil Mary Rose Paradis Joyce Knoll 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1996,10(1):1-6
Pituitary adenomas are commonly reported in older horses. The typical clinical signs associated with this condition, also known as equine Cushing's disease (ECD), are related to increased adrenocorticotropin (ACTH) production resulting in hyperadrenocorticism. The primary purpose of this study was to determine whether plasma ACTH concentrations differed between cushingoid and healthy horses. The second objective was to determine the effects of blood sample handling techniques on ACTH concentrations. A commercial human ACTH radioimmunoassay (RIA) was used to quantify equine plasma ACTH. Intra-assay and interassay variations, as well as dilutional parallelism were determined during the RIA validation. Plasma ACTH concentrations were evaluated in a group of healthy equids composed of 18 horses and 9 ponies, and in 22 equids with a clinical diagnosis of hyper adrenocorticism (11 horses and 11 ponies). The mean plasma ACTH concentrations in healthy horses and ponies, (18.68 ± 6.79 pg/mL (mean ± SD) and 8.35 ± 2.92 pg/mL, respectively), were significantly different (P = .009). The mean plasma ACTH concentration in horses and ponies with ECD, (199.18 ± 182.82 pglmL and 206.21 ± 319.56 pg/mL, respectively), were significantly higher than the mean ACTH concentration in the control animals (P < .001). Plasma ACTH concentrations appeared to be a sensitive and specific indicator of ECD in horses and ponies. ACTH concentrations measured in plasma samples kept at room temperature (19°C) as long as 3 hours after blood collection were not statistically different from those of samples kept at 1°C. J Vet Intern Med 1996;10:1–6. Copyright 1996 by the American College of Veterinary Internal Medicine . 相似文献
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Samii VF Les Clifford M Schulz KS Keyak JH Stover SM 《American journal of veterinary research》2002,63(8):1159-1166
OBJECTIVE: To evaluate subchondral bone density patterns in elbow joints of clinically normal dogs by use of computed tomographic (CT) osteoabsorptiometry. SAMPLE POPULATION: 20 cadaver forelimbs from 10 clinically normal dogs. PROCEDURE: Each elbow joint was imaged in parasagittal and transverse planes of 1.5-mm thickness. Slice data were converted to dipotassium phosphate equivalent density (PPED) values. Sagittal, parasagittal, and transverse medial coronoid process topographic maps were constructed. Defined zones were created for each of the 3 CT planes, and confluence and peak PPED values were determined. RESULTS: The lowest PPED value was 340 mg/ml (articular and subchondral confluence), and the highest was 1780 mg/ml (peak subchondral density). Detectable effects of joint laterality were not found in the confluence or peak PPED measurements or in the peak-to-confluence PPED ratio for all 3 CT planes. Significant differences were found among zones in all 3 planes for confluence and peak PPED measurements and between sagittal and transverse planes for peak-to-confluence PPED ratios. Subjectively, the pattern of density distribution among dogs was fairly consistent for the sagittal and parasagittal slices. Three specific patterns of density distribution were apparent on the transverse topographic maps of the medial coronoid process that corresponded to conformational differences. CONCLUSIONS AND CLINICAL RELEVANCE: The use of CT osteoabsorptiometry provides a repeatable technique that can be used to noninvasively examine bone density and the effects of stress acting on joints in vivo. Variability in density values for any of the CT planes was not identified among clinically normal dogs. 相似文献
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Lobetti R Dvir E Pearson J 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2002,16(1):63-68
This study compared the sensitivity of ECG and cardiac troponins to predict cardiac histopathological changes, clinical severity, and survival in canine babesiosis. One control group (n = 9) and 4 groups of dogs with mild uncomplicated babesiosis (n = 8), severe uncomplicated babesiosis (n = 9), complicated babesiosis (n = 8), and babesiosis and concurrent immune-mediated hemolytic anemia (IMHA) (n = 9) were studied. A 1-minute lead II ECG was recorded, and cardiac troponin I (cTnI) and T (cTnT) concentrations in plasma were measured. cTnI concentrations were significantly higher in the complicated (mean, 9.9; SE, +/-5.76) and concurrent IMHA (mean, 6.53; SE, +/-4.32) groups and in the 3 dogs that died of the disease (mean, 22.17; SE, +/-12.85) than in the control dogs (concentration below detection limit of test, -0.3 ng/mL). The 3 nonsurvivors had the most severe cardiac histopathological changes, but no arrhythmia and minimal other ECG changes. Dogs with babesiosis developed a variety of ECG abnormalities, but the abnormalities were not associated with disease severity, outcome, or plasma cardiac troponin concentrations. The exception was the presence of ventricular premature complexes (VPCs), which were associated with high cardiac troponin concentrations. This study showed an association between cTnI concentration and histological changes, clinical severity, and survival and no correlation between ECG abnormalities and histological changes or biochemical evidence of myocardial damage as reflected by cTnI concentrations. From this study, it was concluded that the analysis of plasma cTnI is a feasible and sensitive test and is superior to cTnT in diagnosing cardiac involvement in dogs with babesiosis. 相似文献