中国内蒙自治区马饲育环境土壤中马红球菌的分布

对中国内蒙古自治区饲育马土壤环境中马红球菌的分布知之甚少;为此,在中国内蒙古通辽近郊、内蒙古南部锡林郭勒盟大草原、内蒙古东部呼伦贝尔大草原等马场共收集了108份土壤样品进行了马红球菌的检测。结果,锡林郭勒盟大草原和呼伦贝尔大草原的马红球菌分离率为25.9%～30.0%,通辽近郊土壤中分离率高达82.3%。这说明在通辽近郊马红球菌的分离菌数是草原土壤中马红球菌分离菌数的10倍。应用PCR技术检测了488株的毒力相关基因,相对分子质量分别为15000～17000（VapA）和20000（VapB）。所有的分离株都未检出毒力相关基因。这些无毒力分离株的质粒资料显示,各种大小的潜在质粒的发生率为13.3%～21.5%。本研究结果截然不同于我们新近对蒙古国的调查结论：马红球菌在蒙古国乌兰巴托的马群中不存在。造成这一差异的原因可能在于蒙古国的游牧生活和内蒙古的非游牧生活。     

灌浆结实期高温对水稻籽粒蔗糖及降解酶活性的影响

选用水稻品种越光和笹锦为材料,在开花后设置自然温度和高温两种处理,研究了不同温度处理下籽粒蔗糖、果糖和葡萄糖含量的动态变化以及蔗糖合酶、液泡型转化酶和细胞壁结合型转化酶活性的差异。高温处理下,蔗糖合酶活性值大于转化酶活性值,且与淀粉积累速率呈显著正相关,表明蔗糖合酶在蔗糖的分解和淀粉的合成过程中起着重要作用;高温下两品种籽粒的蔗糖含量明显增加,但分解的葡萄糖和果糖含量并未相应增加,表明高温有利于籽粒中蔗糖的积累,而不利于籽粒中蔗糖的分解。高温下蔗糖合酶、液泡型转化酶和细胞壁结合型转化酶活性明显下降,表明蔗糖分解速率的下降与蔗糖合酶和转化酶活性下降有关。     

QUANTITATIVE CONTRAST-ENHANCED ULTRASONOGRAPHY OF CANINE SPLEEN

Contrast-enhanced ultrasonography has an important role in the detection of tumors in humans. The second-generation contrast agent Sonazoid has the ability of real-time contrast imaging along with parenchymal imaging. The purposes of this study were to determine the effect and duration of Sonazoid on the changes in gray-scale enhancement of canine spleen and to establish an appropriate protocol for contrast-enhanced ultrasonography of canine spleen. Six healthy beagles were injected with an intravenous bolus of Sonazoid. In the spleen parenchyma, the enhancement was maintained up to 30 min after injection. Moreover, for 5–22 s after injection, gray-scale enhancement of splenic arteries afforded arterial imaging. Perfusion of the kidney may be investigated from 3.6 s to 3.5 min after injection of Sonazoid. These results suggest that Sonazoid is applicable to canine spleen parenchymal imaging and that the optimal time for the parenchymal imaging is 7–30 min after injection. The findings of this quantitative study should prove useful in the evaluation of diffuse or focal splenic and renal diseases in dogs.     

A Preliminary Study of 13C-Phenylalanine and 13C-Dipeptide Breath Tests in Horses

This study aimed to establish a standard dose and sample collection time for ¹³C phenylalanine and ¹³C-Dipeptide breath test in horses. To evaluate dose-dependent effects, healthy horses received 2.5 mg/kg, 5 mg/kg, and 10 mg/kg ¹³C phenylalanine dissolved in 1 ml/kg distilled water and 1.25 mg/kg, 2.5 mg/kg, and 5 mg/kg ¹³C dipeptide dissolved in 2 ml/ kg distilled water. Tmax was observed during the sample collection time. For ¹³C phenylalanine, the standard deviation of Cmax at 5 mg/kg was lower than that of 10 mg/kg. For ¹³C dipeptide, the standard deviation of Tmax was the lowest at 5 mg/kg. This study revealed that an optimal dose for breath tests with ¹³C phenylalanine and ¹³C dipeptide may be 5 mg/kg in horses.     

An insertion/deletion variant of a thymine base in exon 2 of the porcine beta 3‐adrenergic receptor gene associated with loin eye muscle area

An insertion/deletion variant of a thymine base (T5 and T6) in exon 2 of porcine beta 3‐adrenergic receptor (ADRB3) gene has been described. In the current study, we made an association study between the ADRB3 polymorphisms and production traits in 735 Duroc pigs. The allele frequencies for the T5 and T6 alleles in our study population were 0.433 and 0.567, respectively. Any associations between ADRB3 genotype and average daily weight gain during test period, or backfat thickness and intramuscular fat content were not detected in either sex. However the size of the loin eye muscle area (EMA) was significantly associated with ADRB3 genotypes in gilts. T6‐homozygous gilts had a higher mean of EMA (40.6 ± 0.6 cm²) than T5‐homozygous (38.1 ± 0.4 cm², P = 0.002) and heterozygous (38.8 ± 0.3 cm², P = 0.034) gilts. This association was not detected in males. In addition, a multiple traits animal model best linear unbiased predictor (BLUP) analysis revealed that the T6‐homozygous genotype had positive effects on breeding value of EMA. Accordingly, we suggest that ADRB3 polymorphism has the potential to be an important genetic marker for prediction of EMA in Duroc pigs.     

Prognostic value of small intestinal dilatation in dogs with protein-losing enteropathy

To date, little is known about the prognostic significance of ultrasonographic findings in dogs with protein-losing enteropathy (PLE). The aim of this retrospective study was to examine the prognostic value of ultrasonographic findings in dogs with PLE. A total of 26 dogs with PLE were included: 20 dogs with chronic enteropathy and 6 dogs with gastrointestinal lymphoma. The presence of small intestinal dilatation was associated with shorter survival time in dogs with PLE (P=0.003). The presence of hyperechoic intestinal mucosal striations was associated with longer survival time in dogs with PLE (P=0.0085). The results of the current study indicate that the presence of small intestinal dilatation might be associated with poor prognosis in dogs with PLE.