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151.
SUMMARY: Additive genetic and maternal effects were estimated for postweaning growth traits and carcass traits using a derivate-free REML procedure under animal model. The traits studied were weight at 84 days of age, age at slaughter, postweaning ADG, dressing percentage, weight of kidney and pelvic fat, and muscle pH value and electrical conductivity in the semimembranosus muscle. Heritability estimates from a total of 728 rabbits in a reciprocal crossbreeding experiment ranged from 0.15 to 0.26 for postweaning growth traits, 0.21 for dressing percentage, 0.38 for weight of kidney and pelvic fat, 0.02 for pH value, and 0.51 for electrical conductivity. Considerable maternal effects were present in postweaning growth traits and in weight of kidney and pelvic fat. Genetic correlation estimates indicated that genetic selection for postweaning daily gain would lead to lower dressing percentages (- 0.51) and leaner carcasses (- 0.34). The genetic relationships between ADG after weaning and pH value (- 0.90), and between ADG and electrical conductivity (0.58) illustrated a shifting towards a glycolytic energy metabolism of the muscle due to increased growth. Litter size at birth was found to be a significant source of variation for all postweaning growth traits (p < 0.001) and for electrical conductivity (p < 0.05). Genetic selection for litter size at birth would result in decreased growth rates, lower dressing percentage and enhanced adiposis. ZUSAMMENFASSUNG: Die Sch?tzung additiv-genetischer und maternaler Effekte auf Mastleistungs- und Schlachtk?rpermerkmale beim Kaninchen Additiv-genetische und maternale Effekte wurden für Mastleistungsmerkmale nach dem Absetzen und für Schlachtk?rpermerkmale anhand eines Tiermodells (DFREML-Methode) gesch?tzt. Bei den untersuchten Merkmalen handelt es sich um das 84-Tage-Gewicht, das Schlachtalter, Zunahmen nach dem Absetzen, Ausschlachtungsprozente, Nieren- und Beckenfettgewicht und um den pH-Wert und die elektrische Leitf?higkeit im M. semimembranosus. Die Heritabilit?tssch?tzungen an insgesamt 728 Tieren, die aus einem reziproken Kreuzungsversuch stammten, lagen bei den Wachstumsmerkmalen zwischen h(2) = 0,15 und h(2) = 0,26. Sie betrugen h(2) = 0,21 für die Ausschlachtungsprozente, h(2) = 0,38 für das Nieren- und Beckenfettgewicht, h(2) = 0,02 für den pH-Wert und h(2) = 0,51 für die Leitf?higkeitsmessung. Die Sch?tzung genetischer Korrelationen deutet an, da? eine genetische Selektion auf t?gliche Zunahmen nach dem Absetzen zu einer verringerten Ausschlachtung (- 0,51) und zu magereren Schlachtk?rpern führen würde. Die genetischen Beziehungen zwischen den Zunahmen und dem pH-Wert (- 0,90) und zwischen den Zunahmen und der elektrischen Leitf?higkeit (0,58) lassen eine Verschiebung in Richtung eines glykolytischen Muskelenergiestoffwechsels bei verst?rktem Wachstum erwarten. Die Wurfgr??e bei der Geburt stellt eine signifikante Variationsursache für die Mastleistungsmerkmale nach dem Absetzen (p < 0,001) una für die elektrische Leitf?higkeit (p < 0,05) dar. Bei einer Erh?hung der Wurfgr??e durch Selektion sind verminderte Wachstumsraten, geringere Ausschlachtungsprozente und verst?rkte Verfettung zu befürchten.  相似文献   
152.
SUMMARY: The activity of enzyme aldolase (ALD) was determined in the sera of Simmental young bulls, with the purpose to see whether there exists a relationship between the enzyme activity and fattening capacity and whether the ALD could be an indicator of the muscle quantity and protein content. Early ALD activity was correlated with slaughter weight and ADG in the last fattening month. The regression analysis suggests that young bulls with higher serum ALD acitivity at the start of the experiment had more total muscles and less bone in the analysed rib part. On the basis of ALD activity in the first fattening month it was possible to estimate protein and fat content in the MLD. ZUSAMMENFASSUNG: Fructose-1,6-biphosphat Aldolase beim Serum Simmentaler Jungbullen. Beziehung zwischen Mastf?higkeit, Muskelmenge und Proteingehalt Aldolase (ALD) Enzymt?tigkeit im Serum von Simmentaler Jungbullen wurden in Hinblick auf eine Beziehung mit Mastf?higkeit, Muskelmenge und Proteingehalt untersucht. Es zeigt sich eine Korrelation zwischen früher ALD Aktivit?t und Schlachtgewicht und Tageszuwachs im Endmastmonat. Regressionsanalyse ergab, da? Jungbullen mit h?herer ALD Aktivit?t bei Mastbeginn mehr Muskelanteil im m. longissimus dorsi und weniger Knochen besitzen. ALD Aktivit?t im ersten Mastmonat erlaubt Sch?tzung des Protein- und Fettgehalts im m. long, dorsi. RESUMEN: Fructosa 1,6-bifosfato aldolasa en el suero de los terneros simentales. Relatión con sus capacidades de ser cebados, su cantidad de músculos y el contenido de proteínas Con el fin de establecer la relación entre la actividad de enzimas y las capacidades durante el proceso de la ceba, asf como para precisar si el ALD puede servir como indicador de la cantidad de músculos y el contenido de proteinas, intentaba determinarse la actividad de los enzimas de aldolasa (ALD) en el suero de los terneros simentales. A base de la actividad indicial del ALD, es posible estimar el peso final de matadero y la crecencia diaria media durante el último mes de la ceba. Tras una análisis regresiva se ha probado que los terneros con una actividad mayor del ALD en el suero a principios del proceso de su ceba tienen más músculos en total en la parte de costillas y m. longissimus dorsi mientras que tienen menos huesos. A base de la actividad del ALD durante el primer mes de la ceba es posible estimar el contenido de proteinas y grasa en m. long, dorsi. RéSUMé: Fructose 1.6-biphosphate aldolase dans le sérum des taurillons de Simmental. Le rapport entre l'aptitude à l'angraissement, la proportion des muscles et la teneur en protéines On a déterminé l'activité de l'enzyme aldolase (ALD) dans le sérum des taurillons de Simmental afin de vérifier s'il existait un rapport entre l'activité des enzymes et l'aptitude à l'engraissement et si l'ALD pouvait être indicatrice de la proportion de muscles et de la teneur en protéines. A la base de l'activité initiale de l'ALD, il est possible d'évaluer le poids de la carcasse et le gain quotidien moyen au cours du dernier mois d'engrais. Par analyse régressive, il a été établi que les taurillons à l'activité supérieure de l'ALD dans le sérum avaient au début de l'engrais plus de muscles au total dans la région costale et le m. longissimus dorsi et moins d'os. A la base de l'activité de l'ALD au cours du premier mois d'engrais il est possible d'évaluer la teneur en protéines et en graisse dans le muscle longissimus dorsi.  相似文献   
153.
Current literature in veterinary internal medicine regarding the clinical use of the serum bile acids test to assess hepatobiliary function in dogs and cats is reviewed. The test is best used in cases where clinical signs and routine laboratory tests are suggestive of liver disease. It is a highly sensitive and specific test of hepatic function, and is the best method of assessing liver function available to the private practitioner. Abnormal results do not determine etiology, severity, or prognosis of the disorder. They merely indicate the need for hepatic biopsy. The serum bile acids concentration should always be measured in both a fasting and a two-hour postprandial sample.  相似文献   
154.
155.
Malignant catarrhal fever was diagnosed in a newly imported swamp buffalo calf. This disease is prevalent in deer and cattle in New Zealand and causes sporadic losses in these species. The disease is recognised as a problem in buffaloes overseas and this paper records the first case in a swamp buffalo in New Zealand.  相似文献   
156.
Hodge IM 《Science (New York, N.Y.)》1995,267(5206):1945-1947
Physical aging refers to structural relaxation of the glassy state toward the metastable equilibrium amorphous state, and it is accompanied by changes in almost all physical properties. These changes, which must be taken into account in the design, manufacture, and use of glassy polymer materials and devices, present a daunting challenge to theorists.  相似文献   
157.
158.
To assess changes in 24 blood constituents in frozen serum and heparinized plasma, blood samples were drawn from 10 clinically normal German Shepherd army dogs. The storage characteristics of nine enzymes (ALP, ALT, amylase, AST, CK, GGT, GLDH, LDH, lipase), and 15 metabolites and minerals (albumin, bile acids, bilirubin, calcium, cholesterol, creatinine, fructosamine, glucose, magnesium, phosphate, potassium, protein, sodium, triglycerides, urea) were studied. Parallel samples of serum and heparinized plasma were stored for 90 and 240 days at two different storage temperatures, -200 degrees C and -700 degrees C. Sixteen of the 24 analytes (ALP, ALT, amylase, AST, CK, GGT, GLDH, LDH, bile acids, calcium, cholesterol, creatinine, fructosamine, magnesium, phosphate, urea) showed statistically significant (p < 0.05) changes during the storage period related to storage time, storage temperature, and sample type. Seven of the analytes (amylase, GGT, GLDH, LDH, bile acids, fructosamine, magnesium) showed changes of possible clinical importance with mean differences from baseline larger than 20% for the enzymes and 10% for the metabolites and minerals during the storage periods.  相似文献   
159.
The purpose of this study was to determine whether myocardial adenosine triphosphatase (ATPase) activities were reduced in pigs with naturally occurring hypertrophic cardiomyopathy (HCM). The selection of hearts for the HCM and the normal control groups depended on histological examination. Specific ATPase activity and 5-nucleotidase activity were measured in left ventricular myocardium obtained from HCM (n=7) and normal control (n=7) animals. The histological features of HCM included marked disorientation of muscle cells, thickening of the intramural coronary arterial wall with a narrowed lumen, endocardial fibrosis and myocardial fibrosis. The HCM group showed significant increases in both heart weight (32%) and heart weight to body weight ratio (46%). The total ATPase activity in crude homogenates from the HCM group was significantly decreased by 16%. Azide-sensitive ATPase (mitochondrial ATPase) activity, ouabain-sensitive ATPase (Na+,K+-ATPase) activity, basal Mg2+-ATPase activity and Ca2+-ATPase activity were all significantly decreased by 18%, 30%, 20% and 50%, respectively. In contrast, no significant decrease was found in the mean values for 5-nucleotidase activity. These results suggest that myocardial ATPase activities are suppressed in pigs with naturally occurring HCMAbbreviations ATP adenosine triphosphate - gww grams wet weight - HCM hypertrophic cardiomyopathy - Pi inorganic phosphate  相似文献   
160.
1. The perfusion of livers with the vital dye trypan blue was performed to test for evidence of tissue hypoxia in 3 groups of young broiler chickens, namely, ascitic, hypoxia‐induced and controls.

2. Hepatocytes that stained with trypan blue were considered to be dead or dying before fixation and represented damaged cells.

3. The proportion of trypan blue‐stained hepatocytes in the livers of ascitic birds was slightly less than half that observed in the hypoxia‐induced birds but significandy more than the proportion of stained cells observed in control birds.

4. Liver damage in the ascitic birds was also assessed biochemically by an altered enzyme profile.

5. The study demonstrated that increased trypan blue uptake in the livers of ascitic birds reared at sea‐level may be the consequence of hypoxia stress caused by reduced oxygen utilisation.  相似文献   

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