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1.
The reduction of nitrogen (N) excretion in animal production is crucial in intensive farming systems particularly in the developed countries. In this study, a model to predict N excretion in cattle was developed based on existing feeding standards and evaluated using independent N balance experiments for Holstein steers and lactating cows and Japanese Black (JB) steers. Although model predictions for fecal and urinary N excretions appeared to be close to observed values in plot figures, statistical analysis showed that the model tended to over-predict both fecal and urinary N excretions, especially in Holstein lactating cows. This was because body weight changes of cows during lactation period were not considered in the model due to the lack of information (i.e., body weight gain or loss) available in the experimental data for evaluation. There were large mean bias and small line bias for urinary N prediction, but reverse results were obtained for fecal N prediction. The largest mean square prediction errors for both N excretions were due to random variation in all cases. When all data were pooled (combined), the accuracy for predictions for fecal N excretion was considerably high (r2 = 0.94), indicating that the model may predict fecal N excretion beyond breeds, sexes and physiological states (growing and lactating). More information and accumulated data will be required to predict urinary N excretion under a wide range of genotype and environmental situation.  相似文献   
2.
A systematic method is proposed for determination and confirmation of aflatoxin M1 in cheese by liquid chromatography (LC). A sample of cheese is extracted with chloroform, cleaned up on 2 silica gel columns followed by a Sep-Pak C18 cartridge, and chromatographed on a 5 microns octadecyl silica column with fluorometric detection. The sample extract or standard is treated with n-hexane-trifluoroacetic acid (TFA) (4 + 1) for 30 min at 40 degrees C. Analysis by LC with TFA-treatment of the extract provides quantitative data. Multiple assays of 5 samples of Gouda cheese spiked with aflatoxin M1 at levels of 0.5, 0.1, and 0.05 ng/g showed average recoveries of 93.2, 91.6, and 92.4%, with coefficients of variation of 2.63, 3.97, and 4.52%, respectively. Assay of 5 naturally contaminated cheeses resulted in 0.051-0.448 ng/g of aflatoxin M1. Limit of quantitation is about 0.01 ng/g. The identity of aflatoxin M1 is confirmed by treating aflatoxin M1 or the M2a derivative with TFA-methanol (or ethanol) (3 + 1). The TFA-methanol reaction products of M2a could be detected quantitatively.  相似文献   
3.
The outermost layer of skin, the epidermis, is cornified epithelial tissue composed of keratinocytes. To maintain the structure and function of the epidermis, the regulation of proliferation, differentiation, and cornification of keratinocytes is crucial, and various soluble factors secreted by keratinocytes are involved in these regulations. Previously, work has shown that keratinocytes secreted the protein Kdap (keratinocyte differentiation-associated protein) associated with the formation of cornified cell envelopes, a specialized protective barrier structure on the periphery of terminally differentiating keratinocytes. In the present report, the canine counterpart of human Kdap is identified and an attempt has been made to define its physiological role in canine keratinization. Canine Kdap (cKdap) showed structural features commonly observed in other counterparts and is secreted from transfected cells. The expression profile of cKdap mRNA, which was restrictively expressed in cornified epithelial tissues besides skin has also been determined. These findings indicate that there is a strong association between cKdap expression and cornification, which supports previous observations that Kdap is involved in the synthesis and/or degradation of cornified cell envelopes in humans and mice.  相似文献   
4.
This study aimed to examine the effects of feeding kraft pulp (KP) on the growth performance, feed digestibility, and rumen fermentation of Japanese Black fattening steers. Ten Japanese Black fattening steers (aged 26 months) were randomly divided into control and KP groups. The control group (n = 5) was fed concentrate feed without KP, and the KP group (n = 5) was fed concentrate feed containing 10% KP. Both the groups were provided rice straw as roughage. The experiment was conducted over a period of 12 weeks. There was no significant difference in dry matter intake, daily body weight gain, and nutrient digestibility between both groups. No difference was observed in the ruminal concentrations of volatile fatty acids among the groups. At weeks 8 and 12 after the onset of the experiment, the acetate‐to‐propionate ratio in the ruminal fluid of the KP group was significantly higher than that of the control group. The average daily pH of ruminal fluid and activity of ruminal lipopolysaccharide did not differ between the groups. Our results suggested that the growth performance and feed digestibility in the Japanese Black fattening steers were not influenced by replacing concentrate feed with KP.  相似文献   
5.
MytiLec; a novel lectin isolated from the Mediterranean mussel (Mytilus galloprovincialis); shows strong binding affinity to globotriose (Gb3: Galα1-4Galβ1-4Glc). MytiLec revealed β-trefoil folding as also found in the ricin B-subunit type (R-type) lectin family, although the amino acid sequences were quite different. Classification of R-type lectin family members therefore needs to be based on conformation as well as on primary structure. MytiLec specifically killed Burkitt''s lymphoma Ramos cells, which express Gb3. Fluorescein-labeling assay revealed that MytiLec was incorporated inside the cells. MytiLec treatment of Ramos cells resulted in activation of both classical MAPK/ extracellular signal-regulated kinase and extracellular signal-regulated kinase (MEK-ERK) and stress-activated (p38 kinase and JNK) Mitogen-activated protein kinases (MAPK) pathways. In the cells, MytiLec treatment triggered expression of tumor necrosis factor (TNF)-α (a ligand of death receptor-dependent apoptosis) and activation of mitochondria-controlling caspase-9 (initiator caspase) and caspase-3 (activator caspase). Experiments using the specific MEK inhibitor U0126 showed that MytiLec-induced phosphorylation of the MEK-ERK pathway up-regulated expression of the cyclin-dependent kinase inhibitor p21, leading to cell cycle arrest and TNF-α production. Activation of caspase-3 by MytiLec appeared to be regulated by multiple different pathways. Our findings, taken together, indicate that the novel R-type lectin MytiLec initiates programmed cell death of Burkitt’s lymphoma cells through multiple pathways (MAPK cascade, death receptor signaling; caspase activation) based on interaction of the lectin with Gb3-containing glycosphingolipid-enriched microdomains on the cell surface.  相似文献   
6.
The effect of irradiance and temperature on the photosynthesis of two Japanese agarophytes, Gelidium elegans and Pterocladiella tenuis (Gelidiales), was determined using dissolved oxygen sensors and pulse amplitude modulated (PAM) fluorometry. Gross photosynthesis and dark respiration rates were determined over a range of temperatures (8–36 °C). The highest gross photosynthetic rates were 40.3 and 37.0 mg O2 g ww ?1  min?1 and occurred at 24.3 and 25.5 °C [95 % Bayesian credible interval (BCI) 20.7–28.0 and 23.4–28.3 °C], respectively. The dark respiration rate in G. elegans and P. tenuis increased with increasing temperature at a rate of 0.10 and 0.31 mg O2 g ww ?1  min?1 °C?1 , respectively. Modeling the net photosynthesis–irradiance (PE) responses of G. elegans and P. tenuis at 20 °C revealed that the net photosynthetic rates quickly increased at irradiance levels below the estimated saturation irradiance of 88 and 83 µmol photons m?2 s?1, with a compensation irradiance of 14 and 19 µmol photons m?2 s?1, respectively. The highest value of the maximum effective quantum yield (Φ PSII) occurred at 20.1 °C (BCI 18.9–21.5 °C) and 21.3 °C (BCI 20.2–22.5 °C) for G. elegans and P. tenuis and was 0.49 and 0.45, respectively. These optimal temperatures of Φ PSII were relatively lower than those determined by the photosynthesis–temperature model of oxygen evolution. The temperature response of these species indicates that they are probably well adapted to the current range of seawater temperatures in the study site but that they are near the boundary of their tolerable limits.  相似文献   
7.
The objectives of this study were to estimate genetic parameters and to perform a genome‐wide association study (GWAS) for predicted methane‐related traits in Japanese Black steers. The methane production and yield traits were predicted using on‐farm measurable traits, such as dry matter intake and average daily gain. A total of 4,578 Japanese Black steers, which were progenies of 362 sires genotyped with imputed 551,995 single nucleotide polymorphisms (SNPs), had phenotypes of predicted methane‐related traits during the total fattening period (52 weeks). For the estimation of genetic parameters, the estimated heritabilities were moderate (ranged from 0.57 to 0.60). In addition, the estimated genetic correlations of methane production traits with most of carcass traits and feed‐efficiency traits were unfavorable, but those of methane yield traits were favorable or low. For the GWAS, no genome‐wide significant SNP was detected, but a total of four quantitative trait locus (QTL) regions that explained more than 5.0% of genetic variance were localized on the genome, and some candidate genes associated with growth and feed‐efficiency traits were located on the regions. Our results suggest that the predicted methane‐related traits are heritable and some QTL regions for the traits are localized on the genome in Japanese Black steers.  相似文献   
8.
Changes in plasma concentration of lipid composition were analysed in cattle with anemia due to Theileria sergenti infection. Plasma levels of phospholipids, cholesterol, free cholesterol, high density lipoprotein cholesterol, and vitamin E decreased to 40-67% of the pre-infection levels, corresponding to the decrease of PCV due to the infection. However, no definite changes were detected in plasma level of triglyceride. By gradient centrifugation, it was confirmed that lipid components, other than triglyceride, occur in high density lipoprotein (HDL) and these decreases lowered the HDL value. There was no correlation between this phenomenon and liver function. As similar changes in lipid composition were also observed in phlebotomized calves, it was considered that this phenomenon might partially depend on the acceleration of erythropoiesis as a reaction to anemia caused by T. sergenti infection.  相似文献   
9.
The objective of this experiment was to investigate whether the motility parameters and acrosome integrity of goat ejaculated spermatozoa are affected by collecting semen into tubes containing an extender, and thereby determine the significance of reducing contact between seminal plasma and the sperm membrane at ejaculation. Semen were collected from three goats into tubes containing 0, 1 or 10 ml extender, or collected into tubes containing 10 ml extender supplemented with 0.1, 1 or 5% BSA. Sperm motion parameters were evaluated immediately after collection, after washing, and during a 3-h thermal resistance test. Acrosome integrity was assessed using FITC-PNA staining. Semen collection into tubes containing 10 ml extender produced higher sperm motility, progressive motility, and acrosome integrity than that using a smaller volume of extender. Furthermore, collection into 5% BSA-containing extender exhibited higher sperm characteristics and maintained high sperm motility and progressive motility throughout incubation. In conclusion, semen collection into tubes with a large volume of extender, especially extender containing higher concentrations of BSA, improved the quality of ejaculated spermatozoa, strongly suggesting that the in vitro functional characteristics of the spermatozoa were abruptly modified by flash sperm contact with accessory sex gland fluid at ejaculation.  相似文献   
10.
Pressure measurement devices in equine sports have primarily focused on tack (saddle pads and saddle fitting methods). However, saddle pressure devices may also be useful in evaluating the interaction and distribution of normal forces between the horse and rider, including rider position and riding technique. This study examined the validity, reliability, repeatability and possibilities of using a saddle pressure device to evaluate rider position. All measurements were performed using a standing horse. Validity was tested by calculating the correlation coefficient between measured normal force and the weight of the rider. Repeatability was tested by calculating intra-class correlation coefficients. The use of normal force measurements to evaluate horse–rider interaction was tested by adding a known weight to saddle or rider and collecting measurements with the rider sitting in four different positions.The device was found to be valid and reliable for force measurements when the measurement device was not replaced. The system could be used to determine the expected differences with added weight and in different rider positions. The normal force distribution measurement device proved to be a valid and reliable tool for studying the interaction between a rider and a static horse provided it is positioned carefully and consistently relative to both the horse and the saddle.  相似文献   
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