Skeletal muscle characteristics in young trained and untrained standardbred trotters.

Muscle biopsies were taken from the middle gluteal muscle of 28 Standardbred trotters, 3-4 years of age. The 13 horses in Group T were trained consistently from 18 months of age, whereas the 15 horses in Group UT were not exposed to any systematic training before 3 years of age. Group T horses had a lower percentage of Type IIB fibres (31%) than did Group UT horses (39%). Citrate synthase (CS) activity, representing oxidative capacity, was higher in Group T (72 mmol kg-1 min-1) than in Group UT (47 mmol kg-1 min-1). Biopsies were taken from 4 horses in each group when they were foals and then annually until 3-4 years of age. Results from this study indicate that regular training of Standardbreds from 18 months of age resulted in increased CS activity and a decrease in the percentage of Type IIB fibres. This study shows that training, not growth, is the main factor that induces a high oxidative capacity and a high Type IIA/IIB fibre ratio in muscle of Standardbred trotters.     

Investigation of Cervical Patency and Uterine Appearance in Domestic Cats by Fluoroscopy and Scintigraphy

The cervical patency of six domestic female cats was monitored under sedation by infusion of contrast medium (Omnipaque) into the cranial vagina during early oestrus, mid‐oestrus, late oestrus and interoestrus or a radiopharmaceutical (^99mTc‐HSA) during mid‐ and interoestrus in a non‐ovulatory oestrous cycle. The transport of the contrast medium or the radiopharmaceutical through the cervix and within the uterine horns was observed under fluoroscopy and with the aid of scintigraphy. In three of the queens, transcervical transport of contrast medium was demonstrated in all stages of oestrus, in one queen during mid‐oestrus, late oestrus and 1 day after oestrus, and in two queens only during late oestrus. The relations between the cervical patency to the contrast medium and the oestrous behaviour, cornification of the vaginal cells and the serum oestradiol‐17β concentration were evaluated, and a relationship was found between the cervical patency and the degree of vaginal cornification. Transcervical transport of the radiopharmaceutical was observed in three queens during mid‐oestrus. When the cervix was open, hysterography under a fluoroscope and hysteroscintigraphy were performed. The fluoroscopic and scintigraphic recordings revealed the patterns of the uterine contractions during oestrus in both ascending and descending directions, and the movement of the uterine contents back and forth between the uterine horns. The hysterograms were classified according to the shape of the uterine horns and the appearance of the endometrial lining. Spiral‐shaped uterine horns with a smooth inner contour were observed in two queens, and a corkscrew appearance with irregular filling defects in the uterine lumen was shown in two queens that had developed subclinical cystic endometrial hyperplasia. These findings demonstrated that fluids or particles deposited in the cranial vagina of the cat can be transported into the uterus during some stages of the oestrous cycle. The fluoroscopic and scintigraphic techniques developed in this study may be further modified to permit more detailed studies of uterine contractile patterns and sperm transport in the feline female reproductive tract. Hysterography proved useful to diagnose uterine disease. The information on cervical patency is of value also for the development of techniques for artificial insemination in this species, and should be studied also in the ovulatory cycle.     

依托三大支柱发展犬业经济

当今社会科技日新月异，推动着社会文明进程和经济的快速发展，全球犬业呈现出蓬勃生机。纵观国内外犬业发展史，大多以优良品种、训用技术技能、器具研发为犬业的三大支柱，三方面强则犬业兴。笔者现就发展我国犬业的思考抛砖引玉，愿与犬业界有识之士共商。     

Infectious disease serologic survey in free-ranging Venezuelan anacondas (Eunectes murinus).

Reptiles can harbor pathogenic microorganisms asymptomatically and serve as potential reservoirs of infection for humans, domestic animals, and other reptiles. Infectious diseases are also problematic for free-ranging reptile populations and are an important consideration in reptile reintroduction and translocation projects. There have been limited serologic studies of free-ranging reptiles for evidence of exposure to potential pathogens. In the present study, serum or plasma samples from five male and five female free-ranging Venezuelan anacondas (Eunectes murinus) were screened for antibodies to eastern, western, and Venezuelan equine encephalitis viruses, vesicular stomatitis virus, ophidian paramyxovirus, 19 Leptospira interrogans serovars, and Cryptosporidium serpentes. Antibodies to these agents were not detected, or antibody titers were low and possibly nonspecific. These results for the limited number of anacondas surveyed suggest that they do not serve as significant reservoirs for these infectious agents at this location.     

Reproductive roles predict sexual dimorphism in internal and external morphology of lake whitefish,Coregonus clupeaformis

Abstract – The different reproductive roles of the sexes can predict the direction and magnitude of sexual dimorphism of external and internal morphology. Males should have enlarged structures that enhance the acquisition of mating opportunities, whereas females are predicted to have enlarged organs that are associated with the production of eggs. We tested these predictions in male and female lake whitefish, a species in which both sexes have similar overall body size and shape. After controlling for body size, male lake whitefish had significantly longer jaws and pectoral and pelvic fins, larger hearts, and more muscle than females. Sexual dimorphism in relative muscle mass may be one of the most fundamental morphological differences between males and females. Females had relatively heavier livers than males. Because the liver is important for the breakdown of fats and vitellogenesis, selection should favour an enlarged liver in females for the processing of energy and the production of large numbers of eggs.     

北疆棉区打本调控棉纤维生态位适宜度的研究

以北疆高产棉田棉纤维作为研究对象,引入生态位适宜度理论,对三个打原次数不同的处理的棉花群体棉纤维生态位适宜度进行分析研究,结果表明用生态位适宜度来评价棉纤维品质是切实可行的,三个打顶处理中7月10日和7月25日打顶棉株棉纤维生态位适宜度均为中部最高,并且随着棉花群体打顸次数的增加,其下部棉纤维生态位适宜度较上部有逐渐增高的趋势,与一次打顶相比较,其二、三次打顶棉株上、下部棉纤维生态位适宜度均升高.二、三次打顶处理中的6月25日打顶棉株棉纤维生态位适宜度最大值所在部位上移至棉株上部.     

Familial stomatocytosis--hypertrophic gastritis (FSHG), a newly recognised disease in the dog (Drentse patrijshond)

A newly recognised disease, which we have given the provisional name of familial stomatocytosis-hypertrophic gastritis (FSHG), is described in two families of dogs of the Drentse partrijshond breed. The affected dogs consisted of 3 females and 5 males, 3 to 19 (mean 9.5) months of age at admission. The main clinical problems were diarrhoea, icterus, and ataxia and paresis of the pelvic limbs. Laboratory evaluation revealed abnormal red cell shape (stomatocytosis), increased osmotic fragility, haemolytic anaemia, and increased liver enzymes and serum bilirubin. Gastroscopic and histopathologic examination of the gastric mucosa revealed hypertrophic gastritis resembling Ménétrier's disease in man. Histologic findings in the liver were suggestive of progressive liver disease. Cysts were found in the kidneys of the five oldest patients. Electroneurography in 2 dogs revealed polyneuropathy. In the parents of 2 patients (sister and brother), there were no clinical or laboratory abnormalities. An autosomal recessive hereditary defect of lipid metabolism is suspected.     

Identification by isoelectric focusing of creatine kinase-MM isoforms in the plasma and striated muscle of pigs

Total creatine kinase (CK) and CK-MM isoforms were determined in plasma and longissimus dorsi muscle extracts from normal pigs. Based on their total CK activity, the pigs were divided into two groups. Pigs of group 1 (n=16) had a mean plasma total CK of 298±16 U/L and the distribution of the CK-MM isoforms was 65.7±2.5% CK-MM₃, 18.9±1.6% CK-MM₂ and 15.3±1.5% CK-MM. In group 2 (n=18; 826±75 U/L total CK) four isoforms were observed: 3.1±0.9% CK-MM, 67.9±3.0% CK-MM₃, 21.5±2.3% CK-MM₂ and 7.5±1.3% CK-MM₁. The differences between the two groups of pigs were significant (p<0.001) for CK-MM₁ and the presence of CK-MM. Four CK-MM isoforms were also detected in longissimus dorsi muscle homogenates: 45.6±8.1% CK-MM, 32.6±11.7% CK-MM₃, 16.6±2.3% CK-MM₂ and 5.1±2.8% CK-MM₁. The release of CK-MM isoforms from muscle into plasma seems to be unrelated to the concentration of these isoforms in striated muscle.