Comparative biological and biochemical studies in hybrid chicks

The normal course of development of electrophoretic serum protein patterns has been examined in two hybrid strains of chicks during the 7 weeks after hatching and was found to proceed distinctively. Hybrid A (susceptible to aflatoxin) had an almost constant mean serum protein concentration over this period. On the other hand, after a high mean concentration (4–09 g./100 ml.) in day‐old chicks of hybrid B (less susceptible to aflatoxin) there was a fall to 2.69 g./100 ml. at 7 days, followed by a gradual increase to 3.28 g./100 ml., approximately the level found throughout the experiment in hybrid A.

Proportions of albumin and total globulins varied in an almost identical manner in each group. Day‐old chicks of hybrid A had significantly lower β‐ and γ‐globulin concentrations and at 7 days, when there was a maximum difference in mean total protein concentrations, the serum albumin content was significantly higher in this hybrid.     

Corynebacterium pyrogenes; a biochemical and serological study

The study comprises 136 strains of Corynebacterium pyogenes originating from cattle (105), swine (20), sheep (1), and insects (10). For comparison 2 strains of human origin and 1 strain of Gorynebacterium hemolyticum were examined.One of the bovine strains was atypical, being gelatinase-negative, otherwise the strains of Cb. pyogenes were found to be biochemically identical apart from minor deviations in fermentation patterns (Table 1). Neither were antigenic differences demonstrated (gel diffusion analyses, Figs. 1 and 2).Both of the human strains agreed biochemically with Cb. pyogenes (Table 1). By gel diffusion cross analyses one of them was found to be identical with Cb. pyogenes, the other not, though anti-genically related to it (Fig. 2).Gb. hemolyticum deviated biochemically as well as serologically from Gb. pyogenes, but the 2 organisms shared antigenic determinants (Fig. 3).     

Microbiological and serological studies on caprine pneumonias in Oman

Eight of 10 typical cases of contagious caprine pleuro-pneumonia in Oman yielded strain F38-like mycoplasmas from the lungs in high titre, but no other mycoplasmas: both negative animals had been treated with tylosin shortly before death. Among 21 other lungs examined three of six cases of acute pneumonia yielded Mycoplasma ovipneumoniae; one also yielded M capricolum. M ovipneumoniae was also isolated from all eight cases of chronic pneumonia sampled from an abattoir, and from the lungs of three animals which died without overt signs of pneumonia. A single isolate of M arginini and three of unidentified mycoplasmas were also obtained from goats with and without pneumonia. Various bacterial species were isolated, none of which predominated. Antibodies to M mycoides subspecies capri (M m capri) and strain F38 were detected in sera from eight different sources. Assuming titres of 1 in 40 or more as positive in the indirect haemagglutination test used, 29 per cent of 422 serum samples had antibodies to M m capri alone, 2.6 per cent to strain F38 alone and 3.6 per cent to both organisms. These results confirm the presence of F38-like mycoplasmas in Oman, and indicate also widespread infection with M m capri. The role of the latter in caprine pneumonias in Oman requires elucidation.     

Influence of methisoprinol on the replication of rhabdoviruses isolated from carp (Cyprinus carpio) and catfish (Ictalurus melas): in vitro study

Rhabdoviruses constitute one of the most pathogenic viruses isolated from rainbow trout and carp culture. Several viruses were also isolated from other species of fish. These viruses are mostly associated with epizootics and heavy losses. Spring viraemia of carp virus (SVCV) and pike fry rhabdovirus (PFRV) have been the most extensively studied, due to their significant economic impact. Significant progress has been made towards controlling the major bacterial fish diseases using vaccines, but this approach has not yet been successful in preventing viral diseases in fish culture. However, for an effective therapeutic approach, specific drugs should be developed to selectively inhibit virus replication and/or stimulate antiviral protection. In this investigation we examined the in vitro influence of methisoprinol on the SVCV and virus isolated from catfish (Ictalurus melas) replication by measuring their RNA synthesis. The viruses were propagated in EPC cells and cell cultures containing methisoprinol were followed by infection with SVCV or catfish rhabdovirus suspension containing 10(7) TCID50/ml. Methisoprinol (Polfa, Poland) at concentrations of 0, 100, 200, 300, 400 and 500 microg/ml of medium (Glasgow MEM) was used in this study. The results of this study show the strong inhibition of incorporation (cpm) of [3H]-uridine into SVCV and catfish rhabdovirus RNA in cell culture exposed to methisoprinol at various concentrations. The highest percent of inhibition of viral RNA at 72 h after infection with two rhabdoviruses were observed in doses of 400 and 500 microg/ml of methisoprinol in medium. The results of this in vitro study showed that methisoprinol inhibits the rhabdoviruses isolated from carp and catfish.     

不同周龄莱籽鹅和北方白鹅17项血清生化指标的比较研究

分别测定了4、8、12周龄时菜籽鹅(莱菌鹅♂×籽鹅♀)和北方白鹅(东北白鹅♂×籽鹅♀)17种血清生化指标的正常值,并进行比较分析.结果表明,2品种鹅各时期血清生化指标存在不同程度的差异,4周龄莱籽鹅葡萄糖(Glu)含量显著高于北方白鹅(P＜0.05);8、12周龄2品种鹅丙氨酸氨基转移酶(ALT)存在极显著差异(P＜0.01),12周龄莱籽鹅磷(P)含量极显著高于北方白鹅(P＜0.01),而北方白鹅甘油三酯(TG)含量显著高于莱籽鹅(P＜0.05);2品种鹅钙(Ca)、乳酸脱氢酶(LDH-L)及碱性磷酸酶(ALP)都有随周龄增加而减少的趋势,其中Ca含量各时期差异极显著(P＜0.01);而TG、蛋白胆固醇(HDL-C)、天门冬氨酸氨基转移酶(AST)和肌酐含量都随周龄显著升高(P＜0.05),ALP、镁(Mg)、γ-谷氨酸酰基转移酶(γ-GT)、LDH-L含量趋于稳定(P＞0.05).