产蛋鸡饲粮锌和钙水平对蛋的品质和蛋中锌含量的影响

试验研究了在玉米一豆饼型基础饲粮(含锌30Ppm)中添加不同水平锌和钙对鸡蛋品质和蛋中锌含量的影响。结果表明,饲粮未加锌时后期(70～71周龄)蛋壳比,蚕黄,蛋白和蛋壳风干物含量,蛋的比重和蛋壳厚度显著降低;饲粮高钙使中期(45周龄)和后期蛋壳比,各期蛋的比重和蛋壳厚度显著提高。蛋黄中锌含量随着饲粮锌水平的提高而显著提高;蛋白中锌含量在前期(25周龄)同蛋黄一样,但在中期和后期未加锌组鸡蛋白中锌含量显著高于加锌对照组;蛋壳中锌含量在前期不受饲粮锌水平显著影响,在中期和后期饲粮高锌使之显著提高。饲粮高钙对蛋各组分中锌含量没有显著影响。     

Release of tumor necrosis factor-alpha from bovine alveolar macrophages stimulated with bovine respiratory viruses and bacterial endotoxins

The release of tumor necrosis factor-alpha (TNF-) from cultured bovine alveolar macrophages (BAM) was evaluated following stimulation of BAM with bovine herpesvirus-1 (BHV-1), parainfluenza-3 (PI-3) virus, bovine respiratory syncytial virus (BRSV), Escherichia coli 0111:B4 endotoxin, Pasteurella haemolytica type 1 endotoxin, Pasteurella multocida endotoxin, and virus/endotoxin combinations. A cytotoxic assay system using Georgia bovine kidney cells as targets was used to measure TNF- activity. The cytotoxic activity was neutralized by an anti-human TNF- monoclonal antibody.

Stimulation of BAM with 1 median tissue culture infectious dose (TCID₅₀) of live or ultraviolet (UV)-inactivated PI-3 virus/cell resulted in release of TNF- in significantly (P<0.05) higher amounts than sham-induced BAM. The quantities of TNF- released after live or UV-inactivated BHV-1 or BRSV induction were not significantly higher than sham-induced BAM. E. coli 0111:B4, P. haemolytica type 1 and P. multocida endotoxins stimulated TNF- release in a dose-dependent manner. Sequential exposure of BAM to 1 TCID₅₀ per cell of either live BHV-1, PI-3 virus or BRSV and then 5 μg ml⁻¹ of either E. coli 0111:B4, P. haemolytica type 1 or P. multocida endotoxin caused a significant (P<0.05) reduction in detectable TNF- in seven of nine virus/endotoxin combinations tested, when compared with 5 μg ml⁻¹ of endotoxin alone. Parainfluenza-3 virus/endotoxin combinations stimulated higher TNF- release when compared with other virus/endotoxin combinations. Five out of six test animals had serum-neutralizing antibodies to PI-3 virus, one out of six had serum-neutralizing antibodies to BHV-1, and two out of six had serum-neutralizing antibodies to BRSV, suggesting a possible relationship between serum neutralizing antibodies and TNF- release from in vitro cultivated BAM.     

Potential of a recombinant antigen as a prophylactic vaccine for day-old broiler chickens against Eimeria acervulina and Eimeria tenella infections.

A genetically engineered Eimeria tenella antigen (GX3262), produced as a fusion protein with beta-galactosidase and identified with a monoclonal antibody, induced partial but significant protection in young broiler chickens against experimental E. tenella and Eimeria acervulina infections. The antigen appears to share a T-helper cell epitope with the parasite as evidenced by (a) booster inoculation with either the recombinant antigen or with a small number of live oocysts enhanced the protective immunity in GX3262 primed chickens, and (b) ability of the antigen to induce in vitro stimulation of T-cells from chickens immunized with antigen or parasite. These observations suggest the feasibility of a single vaccination of 1 or 2-day-old broilers with GX3262 to induce an acceptable degree of protective immunity. The implications of the observations reported here are far reaching in terms of a practical coccidiosis vaccine for poultry, and show for the first time that 1-day-old broiler chickens can be efficiently vaccinated with a recombinant antigen against one or more species of Eimeria.     

澳洲坚果引种试种研究初报

澳洲坚果无性系从１９７９年开始引入中国，并在南亚热带作物研究所（南亚所）试种，现已在南亚热带地区七省扩大试种达２００ｈｍ＾２，各地生长均良好，已有少量结果。南亚所植区澳洲坚果１３龄树平均单株年产已达６ｋｇ（壳果），抗寒性良好，在－４℃时仍未受害，病虫害不严重（曾发生过花序枯萎病、速衰病、茎干溃疡病），但风害严重。澳洲坚果的适生温度在１０℃－３０℃，以最冷月（１）平均气温≤１０℃，年降雨量在１０００     

Plasma triglyceride concentration during intravenous infusions of propofol and Intralipid in sheep

Plasma triglyceride concentrations were measured in sheep given Intralipid or propofol, which is carried in a vehicle very similar to 10% Intralipid. A bolus dose was administered followed immediately by an infusion of the same agent for 2 h. In the animals that received propofol, the measured concentration increased by a mean amount of 3.39 mmol/l when the infusion rate was l ml/min (Group Pl) and by 7.13 mmol/l when it was 2 ml/min (Group P2). When 10% Intralipid was administered and infused at 1 ml/min (Group I10), the measured concentration increased only by 0.95 mmol/l. One hour after stopping the infusion, the excess of measured concentration over baseline had decreased in the Pl and I 10 groups to 0.52 and 0.13, respectively, of the corresponding maximum excess. The method adopted for measuring plasma triglycerides is widely used in hospitals; however, an incidental observation revealed that it is inappropriate in the presence of injections of propofol or Intralipid. Despite this, evidence and argument are presented to support the conclusion that, with propofol, plasma triglyceride concentrations increased more rapidly during the infusions and returned to baseline more slowly than with a corresponding amount of Intralipid.     

High-resolution computed tomography of the mammalian lung.

High-resolution computed tomography (HRCT) was performed in 21 isolated animal lungs, from 4 mammalian species (pigs, rabbits, dogs, sheep). Gross and subgross central and peripheral lung morphology was determined by HRCT. Three distinct types of lungs can be identified, principally based on the extent of interlobular septal development; the relationship of major vessels to airways; and the thickness of the visceral pleura. Type-I lung is found in pigs, sheep, and cattle; type-II lung is found in rabbits, dogs, cats, and monkeys; and type-III lung is found in human beings and horses. These mammalian lungs were compared with human lungs. The potential use of HRCT to investigate specific human lung diseases in the aforementioned species also was considered.     

Toxic peripheral neuropathy with demyelination in Sprague-Dawley rats given CGS 21595--a 5-lipoxygenase inhibitor.

Male and female Sprague-Dawley rats were given CGS 21595, a pro-drug that is almost immediately metabolized to CGS 19213, a naphthoquinone that acts as a 5-lipoxygenase inhibitor. The compound was administered by gavage to five groups of Sprague-Dawley rats (group Nos. 1, 5, n = 30; group Nos. 2-4, n = 20) at daily doses of 0, 50, 150, 500, or 1,000 mg/kg for 13 weeks. Rats in the higher dose groups had a reduced weight gain, but significant neurologic signs were not observed. A peripheral neuropathy consisting predominantly of myelin destruction in the spinal nerve roots and sciatic nerves in male rats treated with greater than or equal to 150 mg/kg CGS 21595 and in female rats treated with greater than or equal to 50 mg/kg CGS 21595 for 13 weeks. This lesion was not fully reversible after a recovery period of 4 weeks. Lesions consisted of ballooning of myelin sheaths, infiltration by macrophages, demyelination, and occasional areas of remyelination. Axons were generally preserved, and the brain and spinal cord were not affected. Male and female rats in all treatment groups had cytoplasmic hyaline droplets in the proximal renal tubules. This change was reversible after 4 weeks and was not associated with any other adverse effects on the kidney.