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81.
82.
Cezinande Meira Valsair Matos Pessoa Jo?o Carlos Pinheiro Ferreira Gustavo Henrique M. Araujo Marilu M. Gioso Sony Dimas Bicudo Eunice Oba Cassia Orlandi 《Journal of veterinary science (Suw?n-si, Korea)》2006,7(4):387-390
The present study was conducted in order to verify the efficacy of lower doses and alternative routes of a prostaglandin F2α analogue, luprostiol (PGF), for the induction of luteolysis and the precipitation of estrus in nonlactating Nelore cows (Bos taurus indicus). A conventional dose (15 mg) of PGF was compared to doses lower than the conventional dose, which ranges from 10 to 50%, that were administered intramuscularly (IM), intravulvosubmucosally (IVSM), or in the Bai-hui acupuncture site located within the lumbosacral area. The cows were administered PGF 8 day after estrus in the presence of a corpus luteum, and randomly assigned to the following groups: G1 (positive control), 15 mg, IM (n = 23); G2, 7.5 mg, IM (n = 23); G3, 3.75 mg, IM (n = 24); G4, 7.5 mg, IVSM (n = 25); G5, 3.75 mg, Bai-hui acupoint (n = 24); and G6, 1.5 mg, Bai-hui acupoint (n = 25). The results indicated that 50% of a conventional dose of PGF (7.5 mg) resulted in a complete luteal regression (plasma progesterone <1 ng/ml) at Hour 48, and hastened estrus, regardless of whether or not PGF was administered IM or IVSM. Comparatively, 10 or 25% of the conventional dose, even when administered to the Bai-hui acupoint, resulted in an initial reduction in the concentration of progesterone at Hour 24, followed by an increase observed at Hour 48. In conclusion, 25% of a conventional PGF dose administered via the Bai-hui acupoint proved inadequate to induce a complete luteal regression, whereas 50% of a conventional dose administered IM or IVSM was found to be the minimal dose required to induce effectively a complete luteal regression, and to precipitate the onset of estrus in nonlactating Nelore cows. 相似文献
83.
del Castillo JR Laroute V Pommier P Zémirline C Keïta A Concordet D Toutain PL 《Journal of animal science》2006,84(11):3155-3166
Anorexigenic substances released during infection may hinder the therapeutic efficacy of in-feed antibiotics. Paracetamol (acetaminophen; PARA) inhibits the anorexia of infection and seems to improve the clinical efficacy of doxycycline (DOX) against bacterial respiratory disease in swine herds. In order to verify whether PARA selectively stimulates intake of DOX-medicated feed in diseased pigs, we documented the pharmacokinetics (PK) of DOX when coadministered with PARA and examined the effect of in-feed PARA on the interindividual variability in plasma concentrations after systemic exposure to in-feed DOX in swine herds with respiratory disease. Systemic exposure to DOX was measured with the area under the curve (AUC) of its plasma concentrations over time. First, a rich-sampling PK study of in-feed and i.v. DOX (10 mg/kg of BW) and PARA (30 and 10 mg/kg of BW, respectively) was performed on 5 pigs. The PK profiles of in-feed DOX were used in mathematical simulations to determine 5 optimal sampling times for the farm-based population PK study. A randomized, blind, parallel PK study was performed in 2 herds with bacterial respiratory disease, where liquid feed was fortified with DOX alone (5 mg x kg of BW(-1) x meal(-1)) or combined with PARA (15 mg x kg of BW(-1) x meal(-1)). Medicated meals were given twice, 12 h apart, to group-housed growing pigs (n > 50 pigs x treatment(-1) x herd(-1), totaling 215 pigs). Plasma concentrations of DOX and PARA were measured with HPLC. At variance with our expectations, PARA decreased (P = 0.069) mean AUC of in-feed DOX and did not decrease its variability (P > 0.34). Mean AUC of DOX increased with feed intake and with initial exposure to DOX, and was greater in sick animals. Therefore, symptomatic PARA-induced improvement in bacterial respiratory disease control with DOX is more likely caused by its analgesic/antipyretic effects than by its orexigenic effect. Interindividual variation in the AUC of DOX was large in pigs given group medication, even when sufficient feeding space was allowed and the amount of feed offered was greater than their requirements. Therefore, future studies to improve the efficacy of group antibiotic therapy should focus on feeding behavior characteristics as well as biopharmaceutical properties of medicated feeds. 相似文献
84.
Dosage assessment of valnemulin in pigs based on population pharmacokinetic and Monte Carlo simulation 下载免费PDF全文
Y. X. Zhang J. Sun X. Y. Luo L. X. Zhu Z. Zhang R. Wang Y. H. Liu 《Journal of veterinary pharmacology and therapeutics》2015,38(4):400-409
To estimate the valnemulin pharmacokinetic profile in a swine population and to assess a dosage regimen for increasing the likelihood of optimization. This study was, respectively, performed in 22 sows culled by p.o. administration and in 80 growing‐finishing pigs by i.v. administration at a single dose of 10 mg/kg to develop a population pharmacokinetic model and Monte Carlo simulation. The relationships among the plasma concentration, dose, and time of valnemulin in pigs were illustrated as Ci,v = X0(8.4191 × 10‐4 × e?0.2371t + 1.2788 × 10?5 × e?0.0069t) after i.v. and Cp.o = X0(?8.4964 × 10?4 × e?0.5840t + 8.4195 × e?0.2371t + 7.6869 × 10?6 × e?0.0069t) after p.o. Monte Carlo simulation showed that T>MIC was more than 24 h when a single daily dosage at 13.5 mg/kg BW in pigs was administrated by p.o., and MIC was 0.031 mg/L. It was concluded that the current dosage regimen at 10–12 mg/kg BW led to valnemulin underexposure if the MIC was more than 0.031 mg/L and could increase the risk of treatment failure and/or drug resistance. 相似文献
85.
Sahin A Ulutas Z Yilmaz Adkinson A Adkinson RW 《Tropical animal health and production》2012,44(5):1027-1034
A study was conducted to assess the influence of genetic and environmental factors on Brown Swiss calf birth weight, and to
estimate variance components, genetic parameters, and breeding values. Data were collected on 1,761 Brown Swiss calves born
from 1990 to 2005 in the Konuklar State Farm in Turkey. Mean birth weight for all calves was 39.3 ± 0.09 kg. Least squares
mean birth weights for male and female Brown Swiss calves were 40.3 ± 0.02 and 39.0 ± 0.02 kg, respectively. Variance components,
genetic parameters, and breeding values for birth weight in Brown Swiss calves were estimated by restricted error maximum
likelihood (REML)–best linear unbiased prediction(BLUP) procedures using an MTDFREML (multiple trait derivative free restricted
maximum likelihood) program employing an animal model. Direct heritability (h
d2), maternal heritability (h
m2), total heritability (h
T2), r
am and c
am estimates were 0.12, 0.09, 0.23, −0.58, and −0.06, respectively. The estimated maternal permanent environmental variance
expressed as a proportion of the phenotypic variance (c
2) was 0.05. Breeding values were estimated for the trait and used to evaluate genetic trends across the time period investigated.
The genetic trend linear regression was not different from zero. No genetic trend for birth weight was expected, since there
had been no direct selection pressure on the trait. Absence of a trend confirms that there was no change due to selection
pressure on correlated traits. Genetic and environmental parameter estimates were similar to literature values indicating
that effective selection methods used in more developed improvement programs would be effective in Turkey as well. 相似文献
86.
The nitrogen pool of piglets weighing 19.4 +/- 1.4 kg at the beginning of the experiment was labeled with an oral application of ([15N]H4)2SO4 (1.26 [15N]-atom percent excess of dietary N) over a period of 7 d. The labeling period was followed by an equilibration period of 7 d without feeding the labeling compound. The two experimental diets were based on wheat (53%) and rye (25%) and were fed either with or without a xylanase containing enzyme preparation over both experimental periods. Additionally, diets were supplemented with an indigestible marker during the 2nd period of the experiment to allow the calculation of endogenous N-losses in subsequent segments of the digestive tract of the pigs. These endogenous N-losses were estimated at the end of the experiment by analyzing feces, ingesta and urine for [15N]-enrichment assuming that [15N]-enrichment of urine represents the [15N]-enrichment of the precursor pool. Endogenous N-losses were not significantly affected by xylanase addition at any measurement site (stomach, 3 sections of the small intestine, total digestive tract). Endogenous N-proportions of total nitrogen amounted on average for the six pigs to 42 +/- 11% and 56 +/- 5% at the last section of the small intestine and over the whole digestive tract, respectively, which corresponded to endogenous N-losses of 2.8 +/- 1.3 g N/kg DM and 2.0 +/- 0.3 g N/kg DM, respectively. 相似文献
87.
The effects of feeding two fibre-rich diets with contrasting solubility and a concentrated low dietary fibre on the rate of gastric emptying were examined in six gastric cannulated pregnant sows. Additionally, it was examined whether any effect could be related to the physico-chemical properties of digesta, i.e. viscosity and/or water binding capacity. The sows were fed each diet for one week in a 3 x 3 Latin Square design and the samples were taken in a randomised order 0.5, 1, 2, 3, 5 and 15.5 h after the morning meal. The stomach contents were evacuated through the gastric cannula once daily. The evacuated gastric digesta was quantified and a representative sample was taken to determine its viscosity, water binding capacity and its content of dry matter, dietary components and solid (Cr2O3) and liquid (polyethylene glycol) phase markers. The flow of liquid digesta was calculated as the difference between digesta and dry matter. Increasing the content of dietary fibre in the diet led to higher recovery of liquid digesta but did not have any significant effect on the gastric emptying of dry matter and dietary components. The effect of dietary fibre could not be attributed to the viscosity of the liquid phase of digesta but might be related to the ability of the increased gastric dietary fibre content to hold water. The stomach selectively retained the insoluble dietary fibre components most noticeably seen with the bran-supplemented diet where the concentration of insoluble NSP in digesta increased significantly from 2 hours and onward. 相似文献
88.
R G?ltenboth 《Berliner und Münchener tier?rztliche Wochenschrift》1991,104(1):15-18
It is reported of the treatment of a lower jaw fracture, a toe fracture, dislodging of the horn, and fissures in the plantar surface of the foot in three Indian and one Black rhinoceros in Berlin Zoo. Discussed are cause and course of the diseases, and surgical measures taken. 相似文献
89.
The aims of this study were 1) to determine the prevalence of Salmonella in clinically ill birds in aviaries in Ankara, Turkey, and 2) to compare conventional culture and polymerase chain reaction (PCR) for detection of Salmonella in feces from clinically ill pet birds. In the study, 185 fecal samples (feces and/or swabs) collected from the pet birds kept in the seven different aviaries in the city of Ankara were investigated for the existence of Salmonella spp. by bacterial isolation and PCR. The conventional isolation and identification methods were performed for Salmonella isolation from fecal cultures. Suspected colonies were confirmed with the Salmonella polyvalent O antiserum and serogrouped with Salmonella group-specific antiserum. PCR was performed after the fecal swabs were incubated for 18 hr in 10 ml of tetrathionate broth. Three (1.63%) out of 185 fecal samples were found to harbor Salmonella spp. by conventional identification tests and were found to belong to serogroup B. Five (2.7%) swab samples were found to harbor Salmonella DNA by PCR tests. As a conclusion, PCR following incubation of clinical samples in pre-enrichment broth seemed to be a fast and practicable method for Salmonella spp. diagnosis when compared to protracted labor-intensive conventional culture techniques. 相似文献
90.
Lena Steng?rde Madeleine Tr?vén Ulf Emanuelson Kjell Holtenius Jan Hultgren Rauni Niskanen 《Acta veterinaria Scandinavica》2008,50(1):31