Laboratory Animal and Comparative Medicine

Experimental Studies on the Animal Model of Fetal Distress in Ewe

ZHOU Guang-Xing-1, YANG You-Ming-1, LI Xiao-Tian-2, SHI Hao-1, 吕Mei-Ming-1 , ZHAO Wei-Zhi-1, ZHU Ping-Shu-1

1998, 18(1): 1-5.

Asbtract ( 877 )

PDF (7268KB) ( 528 )

Related Articles | Metrics

To establish animal model of fetal distress in ewe,the intrauterine operations were performed on the near-term gestation sheep, and 0.5 ml microsphere （50μm in diameter） suspension at 1% concentration was injected into the fetal abdominal aorta by intravascular catheterization once at 15 minutes interval. The variations in the blood gas and blood acid-base status induced by microsphere injection in the model fetus were moni-tored. The results showed that the variations were similar to clinical signs of fetal distress in human,on the other hand，the maternal blood pH，Pco₂ and Po₂ were maintained rela-tively steady.

Morphometric Analysis of Rat Tendon at Different Growing Ages

CHEN Zhen-Bing, HONG Guang-Xiang, WANG Fa-Bin, HUANG Qi-Shun, WENG Yu-Xiong

1998, 18(1): 6-8.

Asbtract ( 876 )

PDF (4080KB) ( 769 )

Related Articles | Metrics

In order to investigate the morphometric changes of tendons of rats at different grow-ing ages,the tendons of extensor digitorum longus to the middle toes from 0，6 and 12-week-old female Wistar rats were taken for microscopic observation and morphometric analysis. The results showed that with the increase of the age,the tendon blast cells decreased and become slender,collagens increased and become more regular in arrangement,and the diameter of tendons become larger, from 13.1±2.2nm at 0-week-lod to 135.0±21.3nm at 12-week-old. It was concluded that there are marked differences on the morphometry of rat tendons at different growing ages.

Relation between Ocular Growth and Refraction Development in Chick

WANG Fang-Run, HU Lei, LI Jun, JI Hong-Yun, ZHOU Xiao-Dong

1998, 18(1): 9-11.

Asbtract ( 732 )

PDF (5234KB) ( 741 )

Related Articles | Metrics

Three hundred and six newly hatched chicks were applied to explore the charac-ter istics of ocular growth and its relation to refractive development. The refractive state, axial length, equatorial diameter, ocular volume were measured during different periods and the ocular histomorphology was noted. The results showed that the diopter decresed with the age. On days 1 through 56 the refractive state varied from hyperopia （+3.85D） to emmetropia which is the refractive state of maturity with 14mm axial length and 4cm³ ocular volume.The study indicates that it is possible to use chick as an-imal model of experimental myopia.

Mouse Leukopenia Model Induced by Intraperitoneal Injection of Cyclophosphamide and Dynamic Analysis

ZHAO Xi-Xin-1, YAN Du-Hai-1, WANG He-Ping-2, TIAN Kai-Yu-1, DU Cai-Xia-1

1998, 18(1): 12-14.

Asbtract ( 873 )

PDF (4705KB) ( 579 )

Related Articles | Metrics

Leukopenia model were induced by intraperitoneal injection of cyclophosphamide （100,150，200 and 250mg/kg） in KM mice. The peripheral WBC of the mice were decreased dramatically and to the lowest level 4 days after the injection, thereafter began to rise and exceed the pre-injection level at 6th day and then remained for a long period. The lowest level of WBC is linear-negatively correlative with the cyclophosphamide dosage.According to the complete inactivation of cyclophosphamide in the body after 4 hours and the dynamic changes of WBC,the dynamic process and chronaxia of WBC growth were analysed.The results suggested that any chemotherapy resulting in the change of peripheral WBC chronaxia of the model mouse may be considered having the effects on leukopenia.

Effects of Dietary Restriction on Endurance in KM Mice

LUO Xing-Qin-1, SUN Xiu-Fa-2, WU Ai-Guo-2, WANG Ji-Yao-2, WAN Fa-Da-2

1998, 18(1): 15-18.

Asbtract ( 772 )

PDF (5700KB) ( 675 )

Related Articles | Metrics

The weanling KM mice were randomly devided into three groups：group A as control fed with normal diet；group B fed with 80% energy intake of that in group A；group C 65% enegy intake of that in group A.The intake of protein，lipids, vitamins and mineral elements was the same in the three groups. The dietary restriction （DR） was maintained for 3 and 6 months respectively. The results showed：① DR for three months had no significant effect on blood lactate before and after swimming，while in 6 months DR,both 80% and 65% energy intake help cleaning blood lactic acid after swimming. 65% energy intake could decrease the blood lactic acid before swimming （P＜0. 05），and made the change of blood lactic acid with the time at a lower rate than that of group A. These results indicate that DR for longer time can retard the appearance of fatigue and accelerate recovery.② The survivial time of the mice in anoxia condition was significantly different among the three groups,but it seemed to be caused mainly by the difference in body weight.③ 80% energy intake made no significant influence on the ability of resisting against low tempera-ture,65% energy intake for three months could decrease this ability,but after six-month DR the ability was improved.

Breeding of SCID Mice and Its Preliminary Application in Cancer Research

YAO Ming-1, LIU Bing-Ya-2, KONG Han-Wei-1, QI Jin-Fang-1, WU Ren-3

1998, 18(1): 19-22.

Asbtract ( 986 )

PDF (5669KB) ( 651 )

Related Articles | Metrics

SPF SCID mice breeding colony has been maintained successfully in the barrier sys-tem. The reproductive performances and growth of SCID mice were observed. The results showed that the weaning litter sizes were 3. 8±1.3（1♂×1♀）and 4.4±1.6（1♂×2♀），life spans were over 12 months. The microbiological quality monitoring showed that the SCID mice were specific pathogens free. The human tumor cells,including lung cancer （H128）,stomach adenocarcinoma （SGC-7901），brain cancer （U251） and hepatocellular carcinoma （BEL-7402,SMMC-7721），were transplanted successfully onto these SCID mice.The results showed that the human tumor grew much better in SCID mice as compared with those in BALB/c -nu mice. Moreover, metastasis were observed in SCID mice with SMMC-7721 and SGC-7901 transplantaion，especially the later with a high metastatic rate in the liver,lymph node，peritoneum and spleen.

Disinfection Effects of TD Disinfectant on Laboratory Animal Facilities

PENG Qin-Xing, ZHENG Ke-Fan

1998, 18(1): 23-25.

Asbtract ( 1134 )

PDF (4347KB) ( 770 )

Related Articles | Metrics

TD disinfectant has been employed in hospital and used to clean and disinfect vegeta-bles and fruits. It is harmless to both men and animals. The possibility of TD disinfectant to be used in laboratory animal facilities was studied. The results showed that TD could be used for the disinfection of animal cages，air，ceiling and walls of animal rooms at the con-centration of 0.5% （W/V）； 1% TD was available for the disinfection of the floor and cage racks；The disinfection effect of 0. 5% TD was similar to those of 5% lysol and 0.1% bro-mogeramine. These results suggest that TD disinfectant can be employed for the disinfec-tion of laboratory animal facilities.

Diagnosis of Early Pregnancy in Rhesus Monkey by Ultrasonography

LI Zhi-Xiong-1, GAO Ling-Xia-2, FAN Chun-Mei-1, ZHOU Jian-Hua-1, CHEN Xuan-Wu-1

1998, 18(1): 26-28.

Asbtract ( 966 )

PDF (4182KB) ( 562 )

Related Articles | Metrics

Ultrasonic-B was used for the diagnosis of early pregnancy in Rhesus monkey, 23 cases at 18-30 days of gestation were confirmed in 22 with one suspected,15 cases at 31-60 days of gestation were all confirmed by the diagnosis. In early pregnancy monkeys,a region of even and strong echogram and single gestational sac（GS） may be seen in their uteri. Most of the GS were round or oval in shape and the size increased with the length of the gestational period. With the advance of the gestation,fetus and heartthrob of the embryo may be seen. The size of the uterus in normal monkey during breeding season was less than 28mm in length and 22mm in width, no strong echogram region was found in the uterus.

Table of Content