流行性出血灭活疫苗二针与三针接种效果的比较

本文研究人体接种流行性出血热灭活疫苗总量为三毫升时,比较观察分三次接种和分二次接种的反应及免疫效果。试验分三组进行,第一组根据常规方法０、７、２８天免疫三针,每针１毫升;第二组０、２８天免疫二针,每针１．５毫升;第三组０、２８天免疫二针,和一针２毫升,第二针１毫升。结果三组均未发生全身或局部的不良反应,未针１５－３０天,采血测定ＥＨＦ中和抗体,阳转率分别为８７．１％、７９．４％和７６．６％经统计处     

EHF灭活疫苗扩大人体试用的效果观察

流行性出血热(EHF)沙鼠肾细胞灭活疫苗,经75名自愿者扩大试用,未发现不良反应。中和抗体阳转率达70.6～96.7％,4℃保存14个月的疫苗,仍有较高的中和抗体阳转率,再一次证明此疫苗是安全有效的,且有良好的稳定性。接种程序为0、7、28天内三次免疫与0、28、60天内三次免疫无明显差别。皮下接种佐剂苗产生的中和抗体滴度高于肌肉接种的佐剂苗和疫苗。     

流行性出血热灭活疫苗人体试验的反应观察

由流行性出血热(EHF)病毒浙_(10)株感染沙鼠肾细胞,经0.05％β-丙内酯灭活研制成的EHF灭活疫苗,于4℃放置7个月后,对10名志愿者免疫三针(0天、7天、28天各注射1ml)。结果免疫者的局部和全身均无任何副反应。首针免疫后第28天,血清用反向被动血凝抑制试验(RPHIA)、ELISA和间接免疫荧光试验(IFA)检测EHF抗体,分别有9人、9人和8人阳转,第42天,血清用三种方法检测抗体均全部阳转。空斑减少中和试验(PRNT)于第28天有4人阳转,第42天有9人阳转。上述结果表明,此疫苗对人体有较好的的安全性和免疫原性。     

新生儿接种流感嗜血杆菌乙型肝炎偶联疫苗（COMVAX^TM）的安全性和免疫效果研究

将出生时接种过重组酵母乙肝疫苗的131名HBsAg阴性母亲的新生儿,随机分为两组,一组接种COMVAX^TM,另一组接种单价乙肝疫苗和单价流感嗜血杆菌偶联疫苗,出生时第一针乙肝疫苗接种后,应用2,4,13月程序免疫,在2,4月免疫后,接种COMVAX^TM组和对照组新生儿中无一例发生重度副反应,接种COMVAX^TM组新生第一针免疫前（2月）和二针免后一个月（5月）的抗－HBs阳转率分别为53．73％和95．00％,抗全GMT分别为104．10和56．29,均与接种单价组无显著差异,第二针免疫后一个月接种COMVAX^TM组96．00％新生儿抗－PRP抗体达到长期保护临界值（1.0ug/ml)水平,而接种单价流感嗜血杆菌疫苗组新生儿为95．20％,结果表明,对于健康母亲所生的新生儿,接种COMVAX^TM疫苗,抗－HBs和抗－PRP抗体阳转率及滴度均不低于接种单价疫苗组。     

浓缩地鼠肾细胞狂犬病疫苗与纯化Vero细胞狂犬病疫苗接种人体的血清学效果观察

为了解国产浓缩地鼠肾细胞狂犬病疫苗与法国纯化Vero细胞狂犬病疫苗接种人体后中和抗体产生情况。分别用两种疫苗接种 1 0人 ,用小鼠中和试验方法检测中和抗体滴度。国产疫苗五针全程免疫后 30天 (第一针接种后 6 0天 )可 1 0 0 %达到保护水平 ,法国疫苗在第一针接种后 30天 1 0 0 %达到保护水平。第一针接种后 1 4、30、6 0天时 ,前者抗体平均滴度分别是 0 0 6IU /ml、1 .0 2IU/ml、2 .0 7IU/ml;后者抗体平均滴度分别是 0 2 5IU /ml、3.2 4IU/ml、1 1 .86IU/ml,后者比前者产生抗体的滴度高 ,具有显著性差异 (P <0 0 2 )。     

甲、乙型肝炎联合疫苗接种恒河猴的初步观察

为了探索联合接种甲乙肝疫苗、实验性甲乙肝联合疫苗免疫恒河猴的安全性及免疫原性。实验中挑选了甲肝抗体阴性,乙肝两对半阴性,肝功能指标正常的健康恒河猴24只,随机分为10组。混合或分别接种,进行不同毒株的甲肝灭活疫苗与不同厂家的乙肝疫苗的配对效果比较。并接种了实验性甲乙肝联合疫苗;史克甲乙肝联合疫苗试验组。设甲肝单价灭活疫苗L8株、深圳乙肝单价疫苗作为对照。免疫方案0、4、24w。每只恒河猴接种lml。接种3d内,每天观察动物有无不良反应。接种1针和2针后4w内,每2w采集空腹静脉血,以后每4w采血1次检测抗HAV、抗HBs、ALT、AST直至40w。接种疫苗后4、8、24、28w穿刺肝组织做病理学检查。结果显示接种疫苗后3d内,所有恒河猴均无不良反应。ALT、AST无异常升高。4、8、24、28w肝组织无特殊病理改变。注射2针后4w,除3组外,其余各组抗HAV及抗HBs均阳转。3组抗HAV阳转时间迟至12w。全程免疫后12w(即40w),抗HAVGMT为258.75～37489.50mIU/ml;抗HBsGMT为8263.68～60008.064mIU/ml。甲乙肝疫苗联合免疫及实验性的甲乙肝联合疫苗接种恒河猴安全性及免疫原性均良好。     

流行性出血热(EHF)Ⅱ型(家鼠型)纯化灭活疫苗Ⅰ期临床观察

根据卫生部(91)特申体第02号文,92年完成了Ⅱ型纯化疫苗Ⅰ期临床反应及血清效果观察,免疫程序为0,1,2月,分原倍疫苗组和1∶2稀释组,各免15人,每针次免疫后连续观察3天,结果均无不良反应,仅在注射时稍有微胀痛感。二针次免疫后均能产生较高的免疫抗体:原倍疫苗免疫抗体滴度,ELISA1∶181(GET),PRNT中和抗体≥1∶10;1∶2稀释疫苗,ELISA1∶169(GMT),PRNT≥1∶10。三针次免疫后抗体滴度高于二针次;原倍疫苗,ELISA1∶478(GMT),PRNT1∶10～1∶20;稀释疫苗,ELISA1∶446(GMT),PRNT1∶10～1∶20,但原倍疫苗和稀释疫苗的抗体水平之间无显著性差异。半年后仍保持一定抗体水平。可采用二针次总量2ml免疫。     

流行性出血热(EHF)双价纯化灭活疫苗——I 期临床观察

根据卫生部药审(91)特申体第02号文件,本品纯化灭活双价疫苗92年完成了Ⅰ期人体反应及血清学效果观察。91001批双价疫苗以0,1,2月和0,14,35天程序免疫,91002批以0,1,2月程序免疫,各接种15人。接种后未出现任何不良反应,与Ⅰ型,Ⅱ型单价疫苗相同,是安全可靠的。两种免疫程序,二针次免疫后皆能产生较高免疫抗体,接种后半年仍保持一定抗体水平。中和抗体(PRNT)均在1∶10～1∶20,ELISA1∶478～1∶549(GMT),阳转率100％,再次证明本型纯化疫苗安全有效,并具有较高免疫活性,本型疫苗也可采用二针次(0,1月),总量2ml免疫。     

河南省9个县农村地区儿童第二类疫苗接种率及影响因素调查

目的 了解河南9个县农村地区第二类疫苗接种情况及其影响因素,评价第一类替代疫苗现状,为全省提高第二类疫苗接种率和制定第一类疫苗使用策略提供参考依据.方法 采用单纯随机抽样方法,抽取濮阳市、新乡市、南阳市、商丘市、洛阳市5个地市9个县18个乡镇32个村的1 463名2～7周岁农村儿童,疫苗接种知识及主要影响因素从调查儿童监护人获得,疫苗接种记录来自于儿童预防接种证,用EPiData 3.1软件建立数据库,采用Excel 2003和SPSS 17.0进行数据统计分析.结果 9个县农村儿童中第一类替代疫苗率最高的是甲肝灭活疫苗第一针,占20.6％,其次是首针次ACYW135(1)流脑疫苗和AC流脑结合疫苗(1),分别占适龄接种对象的13.8％、12.9％.第二类疫苗以b型流感嗜血杆菌(Hib)第一针次接种率最高,达到46.4％,Hib疫苗三针次接种率为12.6％,其次是水痘疫苗接种率为23.2％;口服轮状疫苗(RV)、23价肺炎(PPV23)疫苗接种率较低,分别为9.5％和7.3％.单因素与多因素logistic回归分析结果表明,接种方式、儿童类别、疫苗价格高低都是影响第二类疫苗接种针次多少的主要因素,乡镇门诊化接种4～6针次和7针次以上的比例分别为22.5％、6.9％,高于村级接种比例12.8％和1.9％;散居儿童疫苗接种针次高于托幼儿童(P＜0.01);监护人文化程度、家庭收入、接种通知方式、儿童是否留守等对二类疫苗接种针次影响不大或无影响(P＞0.05).结论 不同县第二类疫苗替代一类疫苗率和种类不同;第二类疫苗接种率因各地接种方式、价格因素、重视程度和家长认知程度不同而差别较大;扩大以乡为单位接种门诊实施范围、降低第二类疫苗接种价格并加大托幼机构第二类疫苗的宣传等有利于提高第二类疫苗的接种率和接种针次.     

浓缩地鼠肾细胞狂犬病疫苗与纯化Vero细胞狂犬病疫苗接种 …

为了解国产浓缩地鼠肾细胞狂犬疫苗与法国纯化Ｖｅｒｏ细胞狂犬疫苗接种人体后中和抗体产生情况。分别用两种疫苗接种１０人,用小鼠中和试验方法检测中和抗体滴度。国产疫苗五针全程免疫后３０天（第一针按种后６０天）可１００％达到保护水平,法国疫苗在第一针接种后３０天１００％达到保护水平。第一针接种后１４、３０、６０天时,前者抗体平均滴度分别是０．０６ＩＵ／ｍｌ、１０２ＩＵ／ｍｌ、２．０７ＩＵ／ｍｌ;后者抗体平     

Progesterone secretion by induced corpora lutea (CL) of anestrous bitches after administration of gonadotropin-releasing hormone (GnRH) and human chorionic gonadotropin (HOG)

Sixteen bitches were treated with pregnant mare serum gonadotropin (PMSG; 44 IU/kg bwt) intramuscularly (i.m.) for nine consecutive days and each was given 500 IU HOG i.m. on the tenth day or on the first day of induced estrus (Day 0). On Day 12, each bitch was randomly assigned to three groups and treated as follows: Group 1-six bitches, each given 10 mcg GnRH i.m.once every 24 hr; Group 2-six bitches, each given 500 IU HOG i.m. once every 24 hr; and Group 3-four bitches, each given 5 ml 0.9% saline i.m. once every 24 hr. Treatments were continued until Day 55. Blood samples were obtained prior to treatment and every other day until Day 55. Plasma progesterone concentrations were determined by radioimmunoassay (RIA) and data arranged using a split-plot design, with treatment as the main plot and days of sampling as subplots. Analysis of data was by Duncan's Multiple Range Test and treatment-by-day interaction determined by the least-squares method. After treatment, progesterone concentrations from Group 2 were higher (P<0.05) than those of the other groups. A significant effect was seen on Day 20 (P<0.01), while on Day 50 the difference approached significance. These findings suggest that HOG is capable of stimulating the production of progesterone by induced CL in the bitch. However, neither HOG nor GnRH prevented premature regression of these induced CL. Results of this study suggest that premature luteolysis of induced CL is probably not due to lack of gonadotrophic support from either the hypothalamus or the anterior pituitary gland.     

The optimum time for single artificial insemination of blue fox vixens (Alopex lagopus) with frozen-thawed semen from silver foxes (Vulpes vulpes)

During the breeding season of 1991 a total of 608 blue fox vixens aged 1 to 6 years (2.3 +/- 0.1 years, mean +/- SEM) from 2 farms were artificially inseminated intrauterine once with frozen-thawed silver fox semen (1 ml dose containing a total of 150 million spermatozoa). The vixens were allocated to 3 different groups according to the time of insemination. Vixens in Group 1 (n = 203), Group 2 (n = 198), and Group 3 (n = 207) were inseminated on the first, second or third day after the peak value of vaginal electrical resistance, respectively. An overall conception rate of 75% (456 of 608) and 6.0 +/- 0.1 (mean +/- SEM) cubs per litter was obtained. Conception rates and mean litter sizes were significantly different between groups of vixens with respect to day of insemination (P = 0.02, Chisquare, Kruskall-Wallis Test). Vixens inseminated on the second day (Group 2) had the highest conception rate (81%) and the largest mean litter size (7.0 +/- 0.2 cubs) of the three groups, while those inseminated on the third day (Group 3) had the lowest conception rate and mean litter size (70%, 5.4 +/- 0.3 cubs).     

Effect of absorbent pads containing black seed or rosemary oils on the shelf life of sardine [Sardina pilchardus (Walbaum, 1792)] fillets

The effects of essential oils on the shelf life of sardine (Sardina pilchardus) fillets in cold storage were assessed at 4–6°C. The oils were sprayed on the fillets as well as with the addition of absorbent food pads that also contained essential oils. Sardine fillets were divided into eight test groups. Group A: fillets stored without treatment (control group); Group B: fillets packaged with food pads (without the addition of essential oils); Group C: Rosemary oil sprayed onto food pads (10 ml of 1.5% RO); Group D: Black seed oil sprayed onto the food pads (10 ml of 1.5%BSO); Group E: Rosemary oil sprayed onto both sides of the sardine fillets (10 ml of 1.5%RO); Group F: Black seed oil sprayed onto both sides of sardine fillets (10 ml of 1.5% BO); Group G: Rosemary oil sprayed onto both sides of the sardine fillets (10 ml of 1.5% RO) and on the food pads (+10 ml of 1.5% RO); and Group H: Black seed oil sprayed onto the sardine fillets and the food pads (10 ml of 1.5% BSO onto both sides of fillets +10 ml of 1.5% BSO onto food pads). Tests were carried out at days 0, 3, 5 and 7. When compared to the control group, food pads containing rosemary and black seed oils extended the shelf life of sardine fillets by approximately 2 days at 4–6°C. Group A and B exceeded the limit of consumption on day 3, and Group C and D exceeded this microbiological limit after day 5. RO and BSO both exhibited the same antimicrobial effects on the shelf life of sardine fillets. Groups E, F, G and H prolonged the microbiological threshold by 7 days compared to the control. However, Group G and H had 1–1.5 log lower TVC load than Group E and F. Food pads containing antimicrobial essential oils may be used to extend the shelf life of fresh fish, however, further investigations are needed to determine safety standards.     

Bacterioplankton and bacteriobenthos of some floodplain lakes in the course of the lower Amur river

The main structural and functional characteristics of bacterioplankton and bacteriobenthos of three lakes in the lower course of the Amur River are presented: the total number of bacteria (TNB), biomass, the numbers of bacteria of certain aerobic and anaerobic groups; the intensities of methanogenesis (MG), methane oxidation (MO), assimilation of 14C-compounds, sulfate reduction (SR); and gross estimate of organic matter decomposition (D). Depending on the reservoir type and the anthropogenic load, TNB constituted (2.27 to 16.1) x 10(6) cells/ml in water and (1.06 to 10.35) x 10(9) cells/ml in sediments; MO was 0 to 0.28 ml CH4/(1 day) in water and 0 to 8.4 ml CH4/(dm3 day) in sediments; MG in sediments was 0.001 to 40 ml CH4/(dm3 day); SR varied from 0.001 to 24.8 mg S/(dm3 day); D was 0.3 to 25 g C/(m2 day) in water and 0.2 to 4.9 g C/(m2 day) in sediments. The role of anaerobic microbial processes of organic matter decomposition was shown to increase with an increase in the anthropogenic load, attaining 95% of the total D in the ecosystem of an accumulating pond.     

Effect of sequential treatment with prostaglandin F2 alpha and/or oxytocin on estrus and pregnancy rate of lactating dairy cows

A total of 335 lactating dairy cows was used to determine the effect of oxytocin or PGF2a given 8 h after treatment with a luteolytic dosage of PGF2a on the percentage of cows exhibiting estrus within 7 d after treatment, and the pregnancy rate to a single insemination at this time. On the initial day of treatment (Day 0), cows with a palpable corpus luteum on the ovary were treated with 25 mg, im of PGF2a. At 8 h later, the cows were divided into 3 groups. Cows in Group 1 (n = 112) were treated with oxytocin (0.33 IU/kg bwt im); cows in Group 2 (n = 112) were treated with 25 mg, im of PGF2a; and cows in Group 3 (n = 111) served as the untreated controls. Cows in all 3 groups were continuously observed for estrus visually or by way of an activated heatmount detector within 7 d after treatment, and were inseminated within 12 h of the observed estrus.Plasma progesterone (P4) concentration was determined using radioimmunoassay on Day 0 and Day 2. Of the cows with P4 greater than 1 ng/ml on Day 0, the percentage of cows observed in estrus within 7 d after treatment was 75, 89 and 72% for cows in Group 1, Group 2 and Group 3, respectively. When all cows were evaluated, the percentage of cows observed in estrus within 7 d after treatment was 60, 70 and 55% for cows in Group 1, Group 2 and Group 3, respectively. In both instances, the value for cows in Group 2 was significantly higher than that for either cows in Group 1 or Group 3. The pregnancy rate for cows inseminated within 7 d was similar for cows in all 3 groups. The results of this study demonstrated that treatment of dairy cows with 2 luteolytic dosages of PGF2a at an 8-h interval resulted in more cows being observed in estrus within 7 d than with 1 treatment with PGF2a, or with oxytocin given at an 8-h interval after a luteolytic dosage of PGF2a.     

The use of dimenhydrinate in conjunction with dexamethasone for induction of parturition in beef cattle

Forty-eight crossbred Chianina cows (3 to 5 years of age), with an expected gestation length of 288 days, were randomly divided into four treatment groups to evaluate the use of dimenhydrinate (an antihistamine agent) in conjunction with dexamethasone (DEX) for inducing parturition in beef cattle. Group (A) received a 20 mg dose of DEX (im) on day 282 of gestation and a carrier vehicle (iv) 24 hours later (day 283); Group (B) was given a carrier vehicle (im) on day 282 and 500 mg of dimenhy-drinate (DMH) diluted in 200 ml of 2.5% dextrose-0.9% saline solution given (iv) on day 283 and Group (C) received 20 mg of DEX (im) on day 282 and 500 mg of DMH in solution (iv) on day 283 of gestation. The remaining 12 cows assigned to Group (D) were not handled and were allowed to calve under natural conditions. The number of cows calving and percent calving within 60 hours after the first injection were: 10(91%), none(0%) and 12(100%) for the DEX, DMH and DEX plus DMH groups, respectively. The mean gestation length of the control cows in Group (D) was 288.6 days. Frequency of dystocia was: 18.2, 8.3, 0 and 0% and retained placentae (>/=24 hours) was: 72.8, 16.6, 33.3 and 0% for DEX, DMH, DEX plus DMH and control groups, respectively. In this study, a 20 mg dose of DEX (im) followed 24 hours later with 500 mg of DMH (iv) was more successful for calving induction than when DEX or DMH was used alone. The combination DEX and DMH treatment induced calving in a shorter interval from treatment (P<.05) and decreased the incidence of retained placentae (P<.01) when compared with those induced following DEX treatment.     

Ovarian activity in progesterone treated mares following administration of pregnant mare serum gonadotropin

Twelve non-pregnant, non-lactating mares were randomly assigned to four treatment groups using a 2x2 factorial arrangement with three replicates per group. Mares were administered PGF(2alpha) (10 mg, IM) on days -14 and 0, followed by HCG (3000 IU, IM) on day 5. The following treatments were administered: Group A received PMSG on days 2 (4000 IU, IM) and 5 (1000 IU, IV); Group B received PMSG (4000 IU, IM) on day 2; Group C received PMSG (1000 IU, IV) on day; Group D received no PMSG. Mares received progesterone (25 mg, IM) on days 1 through 4. Reproductive tracts were recovered at necropsy on day 16 (10 days post-ovulation). Ovaries were weighed, CL number and weight determined, follicles counted and measured, and volume of follicular fluid quantified. Mean ovarian weight (g) and number of CL per mare, respectively were: Group A, 100.0+/-15.6, 1.7+/-.7; Group B, 128.6+/-40.4, 1.3+/-.7; Group C, 92.4+/-21.0, 2.0+/-.0; Group D, 93.3+/-12.3; .3+/-.3. Mean number of follicles >10 mm and total volume (ml) of follicular fluid per mare, respectively, were: Group A, 9.4+/-2.0, 21.8+/-10.9; Group B, 1.3+/-.3, 32.2+/-28.9; Group C, 4.3+/-1.8, 5.4+/-2.3; Group D, 6.0+/-4.5, 24.0+/-10.3. There was no difference (P>.05) in mean ovarian weight, CL number, CL weight, follicular fluid volume, number of follicles, or size of follicles between treatment groups. These results show no significant effect on ovarian activity in progesterone treated mares following administration of exogenous PMSG.     

Role of endometrial blood flow assessment with color Doppler energy in predicting pregnancy outcome of IVF-ET cycles

This is a prospective study of 182 women (38 yrs or younger) undergoing IVF-ET. Endometrial thickness, echo pattern and blood flow on transvaginal ultrasonography were recorded eight hours prior to hCG administration. The patients were divided into three groups: A (n = 10) with undetectable endometrial blood flow; B (n = 82) with sub-endometrial blood flow; C (n = 90) with both endometrial and sub-endometrial blood flow. According to IVF-ET outcomes, all patients were re-divided into three groups: 1 non-pregnancy (n = 92); 2 intrauterine pregnancy with live fetus (n = 70); 3 others (n = 20 including biochemical pregnancy, embryonic diapause, ectopic pregnancy and miscarriage). Intrauterine pregnancy with live fetus in Group C (62.2%) was much higher than that in Group A and B (0% and 17.1%, p less than or equal to 0.001). The implantation rate (33.2%) was much higher than that in Group A and B (0% and 19.90%, p less than or equal to 0.001). The pulsatility index, resistance index, and S/D of endometrial spiral arteries were 0.1 +/- 0.2, 0.6 +/- 0.1 and 2.5 +/- 0.4 in Group 2, which were much lower than those in Group 1 and Group 3 (p1-2 less than 0.001, p2-3 less than 0.05). The patients with detectable endometrial blood flow had higher clinical pregnancy rates and implantation rates.     

不同周期大剂量地塞米松对初诊ITP的疗效和安全性分析

目的：比较单周期、双周期、三周期大剂量地塞米松治疗初诊原发免疫性血小板减少症（ITP）的疗效和安全性。方法：93名初诊患者按1∶1∶1随机接受单周期（A组：地塞米松每次40 mg每天1次,第1日至第4日）、双周期（B组：地塞米松每次40 mg每天1次,第1日至第4日、第15日至第18日）、三周期大剂量地塞米松（C组：地塞米松每次40 mg每天1次,第1日至第4日、第15日至第18日、第29日至第32日）治疗,比较三组患者的疗效和安全性。结果：93名初诊原发免疫性血小板减少症患者,A组、B组、C组各31名患者,就短期疗效而言,三组相比,停药第7日完全反应率、第14日完全反应率差异均无统计学意义,但是,停药第7日ABC三组的有效率（41.9%vs 70.0%vs 90.0%,P<0.01）、第14日有效率（16.1%vs 36.70%vs 63.3%,P<0.01）差异有统计学意义;就长期疗效而言,三组之间治疗第120日有效率、第60日完全反应率、第90日完全反应率、第120日完全反应率、第90日复发率、第120日复发率差异无统计学意义,但是,第60日有效率（10.0%vs 26.6%vs 53.3%,P<0.01）、第90日有效率（0.0%vs 13.3%vs 30.0%,P<0.01）和第60日复发率（88.9.0%vs 73.3%vs 46.7%,P<0.01）差异有统计学意义,三组治疗相关的不良反应多较轻微,患者大多可耐受。结论：增加大剂量地塞米松的周期,虽没有提高ITP患者的完全反应率,但提高了3月内的有效率,且不良反应可以耐受,可以作为临床用药的参考。     

Plasma progesterone levels during the estrous cycle of Holstein and Brahman cows, Carora type and cross-bred heifers

Daily plasma progesterone (P(4)) was determined during one estrous cycle of 19 cows and 18 heifers of four different breeds: Holstein (H), Brahman (B), Carora-type (C) and crossbred (CB) females. Estrus detection was made by visual observation and using a teaser bull with a chin-ball marker. The P(4) profiles showed no differences among groups. In Group 1 (H), P(4) levels ranged from 0.5 ng/ml plasma on the day of estrus (Day 0) to 5.1 ng/ml at the luteal phase peak (Day 13). In Group 2 (B), P(4) levels ranged from 0.5 ng/ml on Day 0 to 9.2 ng/ml on Day 13. In Groups 3 (C) and 4 (CB), P(4) levels ranged from 0.5 ng/ml, on Day 0, to 13.7 ng/ml on Day 12 and 8.8 ng/ml on Day 13. These last two groups were moved to the same location and then compared. It was found that P(4) concentrations were significantly higher (P < 0.025) in Group 3 between Days 7 and 14 of the estrous cycle. In all groups, P(4) levels were lower than 1 ng/ml one day before the next estrus, and levels of 0.4, 0.5, 0.4 and 0.4 ng/ml were obtained the day of estrus in Groups 1 to 4, respectively. Results indicated that the pattern of P(4) for each one of the groups was similar to those reported by other investigators.