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91.
This paper's objectives were to estimate the genetic (co)variance components of the Gompertz growth curve parameters and to evaluate the relationship of estimated breeding values (EBV) based on average daily gain (ADG) and Gompertz growth curves. Finnish Yorkshire central test station performance data was obtained from the Faba Breeding (Vantaa, Finland). The final data set included 121,488 weight records from 10,111 pigs. Heritability estimates for the Gompertz growth parameters mature weight (alpha), logarithm of mature weight to birth weight ratio (beta) and maturation rate (kappa) were 0.44, 0.55 and 0.31, respectively. Genotypic and phenotypic correlations between the growth curve parameters were high and mainly negative. The only positive relationship was found between alpha and beta. Pearson and Spearman rank correlation coefficients between EBV for ADG and daily gain calculated from Gompertz growth curves were 0.79. The Spearman rank correlation between the sire EBV for ADG and Gompertz growth curve parameter-based ADG for all sires with at least 15 progeny was 0.86. Growth curves differ significantly between individuals and this information could be utilized for selection purposes when improving growth rate in pigs.  相似文献   
92.
Jervis  M.  Huaman  O.  Cahuascanco  B.  Bahamonde  J.  Cortez  J.  Arias  J. I.  Torres  C. G.  Peralta  O. A. 《Veterinary research communications》2019,43(3):165-178
Veterinary Research Communications - Mesenchymal stem cells (MSCs) are found in virtually all tissues, where they self-renew and differentiate into multiple cell types. Cumulative data indicate...  相似文献   
93.
Plasma concentrations of doramectin in 40 cattle dosed by subcutaneous (sc) or intramuscular (i.m.) injection (200 μg/kg) were compared to assess the bioequivalence of the two routes of administration. Peak concentration ( C max), and areas under the concentration curve ( AUC0– ) were determined from plasma concentrations. Animals treated by the sc route showed a mean AUC0– of 457 ± 66 ng±day/mL (± SD) and a mean C max of 27.8 ± 7.9 ng/mL. Results from the i.m. treatment group showed a mean AUC 0– of 475 ± 82 ng-day/mL and a mean C max of 33.1 ± 9.0 ng/mL Absorption constants ( k a) determined by modelling were 0.542 ± 0.336 day-1after sc administration and 0.710 ± 0.357 day-1after i.m. administration. The 90% confidence limits on the difference between mean AUC 0– values for the sc and i.m. groups fell within 20% of the mean value for the subcutaneous group. C max was somewhat greater for the i.m. route. The 90% confidence limits on the difference in mean In ( T max+1) also fell within 20% of the mean sc value. Based on this analysis, bioequivalence of the sc and i.m. formulation has been established.  相似文献   
94.
Furosemide is a problematic drug in a prolonged-release product because its absorption is site specific, taking place mainly in the upper parts of the alimentary tract. The aim of the study reported here was to develop prolonged-release furosemide formulations for dogs. The type of preparation selected was a hydroxypropyl methylcellulose (HPMC) matrix tablet. Evaluation was based on dissolution studies, on in vivo disintegration studies in the canine stomach and on bioavailability studies in Beagle dogs. The variables tested were the viscosity grade of the polymer, the amount of polymer and presence or absence of an alkaline compound (potassium carbonate) in the formulation. When potassium carbonate was included, furosemide was absorbed so slowly that drug administration once daily would give plateau drug plasma concentrations, even though the elimination half-life of furosemide is only about one hour.  相似文献   
95.
SUMMARY: Replicated lines of mice were selected High and Low for adjusted food intake and contemporaneous control lines were maintained. The selection criterion was food intake between 8 and 10 weeks, adjusted by phenotypic regression on mean body weight at 8 and 10 weeks of age to reduce correlated changes in body weight. Responses are given for the first 23 generations of selection, after which adjusted food intake had diverged by a factor of 1.7-1.95. A small correlated response in body weight occurred and mice from the High line were slightly heavier: at 10 weeks of age body weight had diverged by a factor of 1.09-1.11. The realized within-family heritability varied between the replicates from 0.16-0.27 from which a mean estimated mass selection heritability (h(2) = 0.35±0.05) was derived. Mice from the Low line were fatter, however not significantly, because of a High between replicate variance (p > 0.05). Differences in growth over the selection period may account for around 5% of the divergence and increased maintenance costs associated with the larger lean mass of the high lines may explain a further 5%. Mice from the High lines spilled significantly (p < 0.05) more food which accounted for 23% of the divergence in apparent food intake. The heat increment of feeding, brown adipose tissue activity and locomotor activity all appear to be unchanged. ZUSAMMENFASSUNG: Auswirkungen der Selektion auf Futteraufnahme in der adulten Maus In einem Experiment mit Wiederholungen wurden M?uselinien auf hohe und niedrige korrigierte Futteraufnahme selektiert und korrespondierende Konttrollen gehalten. Das Selektionskriterium war die Futteraufnahme im Alter von 8 bis 10 Wochen, die mittels ph?notypischer Regression korrigiert wurde, um die K?rpermasse m?glichst konstant zu halten. Der direkte Selektionserfolg über die ersten 23 Generationen ist beschrieben. Die Linien divergierten zu diesem Zeitpunkt bezüglich des Selektionsmerkmals um 70 bis 95%. In der K?rpermasse trat ein geringfügiger korrelierter Selektionserfolg auf. Die Tiere der 'high'-Linie waren im Alter von 8 bis Wochen ca. um 6 bis 11% schwerer. Die realisierte Intra-Familien-Heritabilit?t variierte zwischen den Wiederholungen zwischen 0.16 und 0.27, woraus sich eine mittlerer Heritabilit?tskoeffizient von h(2) = 0.35±0.05 für die Massenselektion ergab. M?use der 'low'-Linie hatten mit 10 Wochen 2.4% (P > 0.05) und mit 17 Wochen ca. 7% (P < 0.05%) mehr Fett. Mit Unterschieden im Wachstum lassen sich weniger als 5% der Linienunterschiede in der Futteraufnahme erkl?ren. Der h?here Erhaltungsbedarf, der aus einer h?heren fett-freien K?rpermasse in der 'high'-Linie resultiert, k?nnte weitere 5% erkl?ren. Tiere der 'high'-Linie verstreuten deutlich (P < 0.05) mehr Futter, worauf sich 23% der Divergenz in der scheinbaren Futteraufnahme zurückführen lie?en. Die Aktiv?t des braunen Fettgewebes, die lokomotorische Aktivit?t und die fütterungsbedingte Wàrmeproduktion sind scheinbar unver?ndert.  相似文献   
96.
The aim of this work was to record the modifications of the form and amplitude of the electrocardiographic tracings during growth using the Dubois system and to study its sensibility to these physiological changes. This work was carried out on 179 healthy, young and adult Spanish-bred horses (98 females and 81 males). One electrocardiogram (ECG) was obtained from each horse using the Dubois leads system. The bifid shape deflection of the P wave was generally more frequent than the simple one in animals at 4 months of age or older. Amplitudes of the P2 component and of the simple positive wave presented significant differences (p < 0.01) between the age groups studied: animals up to 3 months in age and older than 2 years of age (highest amplitudes), and the rest of the animals (lowest amplitudes). Significant variations (p < 0.05) were found for the QS amplitude between animals of 1 month of age, and all the other groups. The multiple range analysis did not define a clear distribution of age groups for the amplitude of the T wave. It may therefore be concluded, that in the Spanish-bred horse up to 1 month of age, the form and amplitude of the QRS complex in the Dubois leads system differ from those of older animals. Thus, this study shows the sensibility of the Dubois leads system for detecting the electrocardiographic changes related to the growing process in the Spanish-bred horse. In addition, it provides standard values of electrocardiographic parameters in the Spanish-bred horse at different stages of growth.  相似文献   
97.
Red-leg syndrome (RLS) is one of the main infectious diseases that cause economic losses in Lithobates catesbeianus hatcheries, Citrobacter freundii being an etiological agent. Treatment or prevention with therapeutics or chemicals results in modifications of the indigenous microbiota, development of antibiotic resistance, presence of their residues in food and enhancement of production costs. Thus, probiotics could be used as an alternative therapy. Lactic acid bacteria are part of the indigenous microbiota of healthy frogs and can prevent pathogen colonization by different mechanisms, including the production of antagonistic substances. In this work, the evaluation and characterization of the inhibition of C. freundii CFb by Lactococcus lactis subsp. lactis CRL 1584, a potentially probiotic candidate, were carried out. This strain produced lactic acid, H(2)O(2) and bacteriocin in static and shaken conditions and inhibited pathogen growth in associative cultures, with an earlier inhibition under agitated conditions. The elimination of each of the antimicrobial metabolites partially abolished the inhibition of the pathogen, suggesting that the inhibitory effect could be attributed to a combined action of the three antagonistic molecules. Electron microphotographs revealed the damage caused by L. lactis CRL 1584 supernatants to C. freundii cells. The addition of pure lactic acid, H(2)O(2) and bacteriocin to the culture media showed that each metabolite caused different morphological modifications in C. freundii, in agreement with the effect on viable cell counts. The results support the possibility that L. lactis CRL 1584 might be considered as a probiotic to be used in the prevention of RLS in raniculture.  相似文献   
98.
Hemophagocytic syndrome (HPS) is a macrophage hyperactivation disorder triggered by disrupted T-cell macrophage cytokine interaction. HPS has been reported in humans, dogs, cats, and cattle, and it is infrequent and poorly characterized in animals. A 16-year-old male rhesus macaque was euthanized because of severe pancytopenia, including nonregenerative anemia (hematocrit = 5.5%), neutropenia (0.29 K/μl), and thrombocytopenia (21 K/μl). Bone marrow was hypocellular with normal maturation, myeloid hypoplasia, and few megakaryocytes. There were numerous morphologically normal macrophages (12% of nucleated cells), with 6% of nucleated cells being hemophagocytic macrophages in the bone marrow. Serology was negative, but polymerase chain reaction and immunohistochemistry were positive for simian retrovirus type 2. Blood and bone marrow findings were consistent with HPS. Cytopenias are common in simian retrovirus-infected macaques, but HPS has not been reported. An association between simian retrovirus infection and HPS is undetermined, but retrovirus-associated HPS has been observed in humans.  相似文献   
99.
The current cervical artificial insemination (CAI) procedure, involving deposition of excessive sperm numbers, is uneconomical for pig industry. The most obvious alternative requires uterine deposition in combination with fixed-time AI, which would reduce the number of sperm required per pregnant sow, thus allowing the best use of valuable boars and, ultimately, the commercial integration of frozen-thawed and sexed sperm. This review depicts possible best ways to implement an efficient use of liquid-stored, frozen-thawed and sexed sperm by the pig industry.  相似文献   
100.
Five Boxer dogs with a new neurological disease are described. There is a progressive ataxia and weakness, initially in the hind-legs but later involving forelegs. The onset of signs is usually around 6 months of age although an older dog was affected. Proprioceptive function, muscle tone and tendon reflexes are diminished or absent while pedal reflexes and pain sensation are preserved. Muscle atrophy is minimal. The peripheral nerves are depleted in myelinated fibres. Nerve roots and, to a lesser extent, peripheral nerves show demyelination/remyelination changes and in the cervical ventral roots in particular, regenerative clusters are present. Forelimb muscles show evidence of re-innervation. In the CNS numerous swollen axons are present. The dorsolateral and ventral columns of the spinal cord are affected throughout their length. In the brain a number of nuclei and tracts, particularly in the lower brain stem, are affected and the superior olives are severely involved. The cerebral cortex and subcortical white matter appear normal. Various portions of the auditory and optic pathways are affected pathologically as are a number of cranial nerves. The axonal swellings contain a number of organelles including smooth endoplasmic reticulum, disordered neurofilaments, vesicles and mitochondria. The disease may be specific to Boxer dogs and may be inherited.  相似文献   
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