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931.
Malignant catarrhal fever was induced in cattle and rabbits inoculated intranasally with cell-free wildebeest-calf nasal and ocular secretions. This method of reproducing the disease is similar to that occurring in nature and should prove useful as a means of challenging experimentally induced immunity.  相似文献   
932.
Three samples were selected representing bread, soft, and durum wheat. Uniaxial compression and stress relaxation tests were performed on wheat kernels. Force‐deformation curves from intact wheat grain typically exhibited at least two points of inflection (PI) at ≈0.1 and 0.2 mm displacement. The first PI is related to the mechanical properties of all the bran layers. The second PI (0.2 mm) seems to be the endosperm boundary near the aleurone layer. These structures had higher degree of elasticity (DE) compared to the inner endosperm (0.5–0.6 mm). Besides wheat class and specific structures of the caryopsis, moisture content is a prominent factor affecting the mechanical strength of kernels. Stress relaxation tests show that bread wheat kernels with 69.2% DE at 13% moisture decreased to 31.6% DE with additional 6% moisture content. Soft wheat kernels DE of 61.0% at 13% moisture decreased to 22.7% at 19.7% moisture. Stress relaxation revealed pronounced time‐dependence. However, the differences of stress values at 120–180 sec were not significant in all wheat classes and moisture contents evaluated. The stress values after 120 sec might be attributed to the elastic deformation of the kernels.  相似文献   
933.
The impact of pelleted diets with different mineral compositions on the crown size of the mandibular cheek teeth, as well as the mandibular bone and cheek teeth density, in degus (Octodon degus) was investigated. A total of 28 animals were randomly divided into four groups and fed different calcium or phosphorous dietary content, in the presence or absence of UV light, for 14 months. Dental radiographs and CT images of the head were taken, and the crown size of premolar and molar teeth was recorded. Apical and coronal crown elongation of all cheek teeth and significantly smaller relative cheek teeth and mandibular densities were recorded in degus fed a high-phosphorus diet with an improper calcium:phosphorus ratio. A diet with a calcium:phosphorus ratio of 1:1 was also responsible for the rapid development of dental disease with subsequent severe health impairment.  相似文献   
934.
奶牛精确饲喂技术的实施不仅能够促进奶牛业健康发展,而且还能够提高牛场经济效益。基于牛场现状,该文在设计的等径双螺旋精确给料的奶牛饲喂装置基础上,理论分析了物料输送速度与给料时间,通过Solidworks对双螺旋给料装置进行了三维建模,并利用EDEM软件分别对40 mm搅龙和70 mm搅龙不同转速(80、100及120 r/min)的给料过程进行了离散元仿真,分析了装置给料稳定性,结果表明,40 mm搅龙在转速为120 r/min时变异系数为0.052 2,70 mm搅龙在转速为100 r/min时变异系数为0.105 2,给料稳定性最优。为进一步验证仿真结果,在搭建的双螺旋给料饲喂装置上,对40 mm搅龙和70 mm搅龙进行了给料试验,试验结果显示,40 mm螺距搅龙转速120 r/min和70 mm搅龙转速100 r/min时给料稳定性最优,试验结果与仿真结果吻合。在验证装置给料稳定性基础上,对给料精度进行了试验,结果显示:40 mm搅龙和70 mm搅龙在80、100、120 r/min等不同工作转速组合下,给料精度均大于95%,当40 mm搅龙转速为120 r/min,70 mm搅龙转速为100 r/min时,给料时间为14.1 s,给料量为6.009 kg,装置给料精度不低于99.835%,符合奶牛精确饲喂效率与精度要求。  相似文献   
935.
The relationship of glass transition temperature Tg and moisture content (MC) gradient of rice kernels to head rice yield (HRY) variation was investigated. Mathematical models describing heat and moisture transfer inside rice kernels during drying were developed and solved using the finite element method. Moisture distributions inside a kernel were simulated and verified using thin-layer drying experiments, and the intra-kernel MC gradients during drying were accordingly determined and analysed. Results showed that in the glassy region, rice did not incur measurable HRY reduction after drying. However, when rice was dried in the rubbery region and then cooled down immediately without being tempered following drying, HRY decreased markedly after MC gradients exceeded certain levels. It was found in this study that the time when the percentage point of moisture removal reached a maximally allowable level before HRY decreased dramatically coincided with the time at which the curve of kernel MC gradients versus drying duration reached its peak. Such a relation was verified with the HRY data of two varieties (Cypress and M202) as measured in this study and cited from literature. The HRY trends for these two varieties were well explained through the behaviour of glass transition and MC gradients of rice.  相似文献   
936.
To determine the plasma pharmacokinetics of suppository acetaminophen (APAP) in healthy dogs and clinically ill dogs. This prospective study used six healthy client‐owned and 20 clinically ill hospitalized dogs. The healthy dogs were randomized by coin flip to receive APAP orally or as a suppository in crossover study design. Blood samples were collected up to 10 hr after APAP dosing. The hospitalized dogs were administered APAP as a suppository, and blood collected at 2 and 6 hr after dosing. Plasma samples were analyzed by ultra‐performance liquid chromatography with triple quadrupole mass spectrometry. In healthy dogs, oral APAP maximal concentration (CMAX=2.69 μg/ml) was reached quickly (TMAX=1.04 hr) and eliminated rapidly (T1/2 = 1.81 hr). Suppository APAP was rapidly, but variably absorbed (CMAX=0.52 μg/ml TMAX=0.67 hr) and eliminated (T1/2 = 3.21 hr). The relative (to oral) fraction of the suppository dose absorbed was 30% (range <1%–67%). In hospitalized ill dogs, the suppository APAP mean plasma concentration at 2 hr and 6 hr was 1.317 μg/ml and 0.283 μg/ml. Nonlinear mixed‐effects modeling did not identify significant covariates affecting variability and was similar to noncompartmental results. Results supported that oral and suppository acetaminophen in healthy and clinical dogs did not reach or sustain concentrations associated with efficacy. Further studies performed on different doses are needed.  相似文献   
937.
1. A dose–response experiment with 6 dietary choline concentrations (0, 342, 779, 1285, 1662 and 1962 mg/kg) was conducted with male White Pekin ducks to estimate the choline requirement from 21 to 42 d of age.

2. Ninety 21-d-old male White Pekin ducks were allotted to 6 dietary treatments, each containing 5 replicate pens with three birds per pen. At 42 d of age, final weight, weight gain, feed intake and feed/gain were measured. Liver was collected to determine total liver lipid, triglyceride and phospholipids.

3. Significant positive effects of dietary choline on final weight, weight gain and feed intake were observed. In addition, dietary choline supplementation significantly decreased liver lipid and triglyceride content and increased liver phospholipids of Pekin ducks.

4. According to broken-line regression analysis, the choline requirements of male White Pekin ducks from 21 to 42 d of age for weight gain, feed intake and total liver lipid were 980, 950 and 1130 mg/kg. Pekin ducks needed more choline to prevent excess liver lipid deposition than to maintain growth.  相似文献   

938.
microRNA (miRNA) and piwi‐interacting RNA (piRNA) are two classes small non‐coding regulatory RNAs that play crucial roles in multiple biological processes such as spermatogenesis. However, there are no published studies on conjoint analysis of miRNA and piRNA profiles among cattle, yak and their interspecies (the dzo) using sequencing technology. Next‐generation sequencing technology was used to profile miRNAs and piRNAs among those three ruminants to elucidate their functions. A total of 119, 14 and six differentially expressed miRNAs were obtained in cattle vs. dzo, cattle vs. yak and yak vs. dzo comparison groups, while there were 873, 1,065 and 1,158 differentially expressed piRNAs in those three comparison groups. The expression of three miRNAs was validated in the three ruminants, and the results suggested that the miRNA expression profiles data could represent actual miRNA expression levels. Moreover, the putative targets of differentially expressed miRNAs were predicted by their own genome, it is worth to note that both the cattle and yak genome were used for dzo, then the targets were subjected to GO enrichment and KEGG pathway analysis, revealing the likely roles for these differentially expressed miRNAs in spermatogenesis. In conclusion, this study provided a useful resource for further elucidation of the miRNAs and piRNAs regulatory roles in spermatogenesis. It may also facilitate the development of therapeutic strategies for dzo reproduction research.  相似文献   
939.
The response of a salt‐tolerant line ILL 6793 and a salt‐sensitive line ILL 6439 of lentil (Lens culinaris) to N deficiency was studied in a pot experiment under glasshouse conditions. Plants of the two lines were treated with 56, 28, 14 and 7 mg N L?1 in Rorison's nutrient solution. The salt‐tolerant line excelled the salt‐sensitive line in relative biomass production (per cent of control basis) under varying N regimes. Of the various physiological/biochemical variables measured in the present study only chlorophyll b and total soluble sugars proved to be helpful in discriminating the lines. Chlorophyll b was significantly greater in ILL 6793 as compared with ILL 6439 at the two lower N levels. Total soluble sugars increased consistently in both lines with decrease in N level of the growth medium and the salt‐tolerant line ILL 6793 had significantly greater soluble sugars than the salt‐sensitive ILL 6439 at 28 and 14 mg N L?1. Chlorophyll a and free amino acids were uniformly reduced in both lines with decrease in N levels. The salt‐tolerant line showing high efficiency for N utilization could be of great economic value in terms of its use in salt‐affected soils which are usually deficient in N provided it also produces reasonable grain yield.  相似文献   
940.
Uncoupling protein 1 (UCP-1) was believed to be an exclusive protein found in the brown adipose tissue of small rodents and humans; however, recent studies show that the expression of UCP-1 protein has been found in the sebaceous glands of the mouse tail and human skin. There are a few reports about the presence of UCP-1 in the sebaceous glands of other rodents, such as the Sunda porcupine (Hystrix javanica), a wild spiny rodent commonly found in Indonesia with a large sebaceous gland. The aim of this study was to identify the presence of UCP-1 in the sebaceous glands on the skin of the Sunda porcupine. The skin from three regions (thoracodorsal, lumbosacral and apex caudal) of eight adult Sunda porcupines was used to detect UCP-1-immunopositive cells through immunohistochemistry. All three regions were found immunopositive to anti-UCP-1 antibody in the sebaceous gland of quill and hair follicles, and the epidermal layer in quill and hair follicles with various intensities. The result of immunohistochemistry revealed that the thoracodorsal and apex caudal region was the most intense immunoreaction followed by the lumbosacral region. These findings proved that the presence of UCP-1 was also identified in the sebaceous glands of other rodent (Hystrix javanica) and regions of the body, which has not been reported previously.  相似文献   
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