鸭隐孢子虫病调查及雏鸡感染试验

河南省郑州、尉氏、信阳三个地区２１个鸭场２３群共３４４００多只家鸭隐孢子虫感染情况调查结果：２３群家鸭共有１６群感染有隐孢子虫，群体感染率为６９．５７％；不同月龄的家鸭均有感染，１～８月龄鸭感染率（８７．５％）明显高于８月龄以上鸭的感染率（６０％）。所有阳性鸭群中粪便卵囊数均较少。所查卵囊均呈卵圆形、淡红色、卵囊壁单层、光滑无色。测得１００个卵囊大小为３．９～５．７×５．０～６．１（微米），平均为４．７６微米×５．７５微米，卵囊形状指数为１．０５４～１．４３９，平均为１．２２１。鸭源隐孢子虫卵囊感染１日龄海兰雏鸡后，潜隐期４天、显露期１３天。涂片检查发现喉头、气管、肺脏、十二指肠、法氏囊有大量虫体寄生     

湖南省牛的隐孢子虫病调查及小鼠感染试验

对湖南省８个县（市）的２９６头奶牛、１７７头水牛及１２头黄牛进行了隐孢子虫病的调查。发现６个县（市）的牛有隐孢子虫的感染。奶牛感染率为５．３％～２８．８％，其中某牧场１岁以下犊牛的感染率（４６．７％）高于１岁以上牛（２３．９％），３、４月龄犊牛的感染率（分别为１００％和６０％）高于４月龄以上的犊牛；水牛感染率６．６％～４０％；黄牛中未发现隐孢子虫感染。以牛粪中分离出的隐孢子虫卵囊人工感染小鼠成功，     

湖南省部分地区禽隐孢子虫感染情况调查

从湖南省长沙、益阳、常德３市６个鸡场的４３６只鸡,２个鸭场的１６０只鸭,２个鸽场的３２只鸽,１个鹌鹑场的３０只鹌鹑采粪样检查。结果,３个市的鸭均有隐孢子虫感染,感染率分别为４．５９％和３．７５％。其中２￣１８周龄鸡的感染率为７．１４％,２５￣６０周龄鸡的感染率为１．５１％;ＡＡ鸡,伊莎鸡和艾维茵鸡的感染率分别为５．５６％、５．２１％和３．３３％,罗曼鸡,长沙黄鸡为阴性,鸽和鹌鹑未查到隐孢子虫。剖检     

宁夏鸡隐孢子虫病调查及人工感染试验

１９９４年８月至１９９６年１０，对宁夏回族自治区银南，银北，固原３地区１２县（市）４个鸡场共计４５９０４只鸡进行了隐孢子虫感染情况抽样调查。结果，隐孢子虫阳性率达３６．８１％，其中蛋用鸡阳性率为３７．５３％，肉用鸡阳性率为３６．２３％，差异不显著，银南，银北，固原三地区阳性率分别为５４．５５％，４１．９４％和１１．００％，银南地区感染率显著高于固原地区。     

不同蛋白质水平饲粮对蛋鸡育成期的生长发育及产蛋性能的影响

试验选用４２日龄罗斯父母代母雏４５０只，研究１２．５％（１组），１４％（２组），１２．５％－１６％（３组）三个不同蛋白质水平饲粮对育成鸡的生长发育成后的生产性能的影响。结果表明，１，２，３组１４周龄体重分别为本品种推体得的９５．８％，１０１．４％５ １０３．８％；２０周龄体重２分别为标准体重的９５．７％，１００５和１０．７。２１周龄改为同一蛋鸡饲粮后，２３－４３周龄产蛋率１－３组分另显７８．２５％     

饲料产品介绍

吉林省仁亿饲料有限公司 品名适用阶段添加比例（％）价格《元／吨）肉小鸡预混料０～２１天１、４、５面议肉中鸡预混料２１～４３天１、４、５面议肉大鸡预混料４３天～出栏１、４、５面议蛋雏鸡预混料０～８周　１、５面议蛋鸡育成期预混料９周～５％开产１、５面议蛋鸡产蛋期预混料５％开产～淘汰１、５面议种雏鸡预混料０～８周　１、６面议种鸡育成期预混料９周～开产１、６面议种鸡产蛋期预混料５％开产～淘汰１、６面议乳猪预混料生后７天～１５千克１、１２面议小猪预混料１５千克～３０千克１、４面议中猪预混料３０千克～６０千…     

南京地区犊牛隐孢子虫感染情况调查

以南京地区３个奶牛场的５５头６月龄以内的犊牛为调查对象，在１６头犊牛的粪便中查到隐孢子虫卵囊，平均感染率为２９．１％（１６／５５）。Ａ、Ｂ２个奶牛场犊牛的感染率（分别是４０．０％和３５．７％）高于Ｃ场犊牛的感染率（１９．２％），但３个奶牛场感染率的统计学差异不显著（Ｐ〉０．０５）。各奶牛场１～３月龄犊牛隐孢子虫的感染强度和感染率均比４～６月龄犊牛高（Ｐ〈０．０５）。     

岭南黄鸡快,慢羽品系的生产性能

岭南黄鸡快、慢羽新品系雏鸡在出壳后２４小时内利用羽速自别雌雄的准确率达９４．１％，快羽Ｃ系和慢羽Ｄ系０，４，８，１２周龄的平均体重及１２周龄的料肉比的差异均不显著（Ｐ＞０．０５）；１２周龄存活率快羽Ｃ系为９５．０３％，明显高于慢羽Ｄ系的８８．７６％。     

家鸡住肉孢子虫调查及实验感染研究

作者于１９８９年３月到１９９０年３月对昆明市２８４只家鸡进行了住肉孢子虫流行病学调查，在６只家鸡中检到了住肉孢子虫包囊，自然感染率为２．１％。包囊呈梭形，大小为８６５．５×８２．３μｍ，包囊中充满大小为１４．３×２．９μｍ的梭形缓殖子。鸡颈部、背部和大腿部肌肉中包囊密度较高，心肌无包囊寄生。４只犬和５只猫分别于实验感染包囊后第８ｄ和第１３ｄ排出孢子，剖检时小肠粘膜固有层中亦查到孢子。１０只１５日龄     

鸡线虫对雏鸡成活率及发育的影响

通过雏鸡人工感染鸡蛔虫和异刺线虫的试验证明，鸡蛔虫、异刺线虫单独或混合感染，对雏鸡的成活率及发育均有程度不同的影响。与不感染对照组相比，感染３００个／只蛔虫卵的雏鸡成活率低１９％（Ｐ＜０．０５），死亡峰期在感染后７～１４天，增重低３０．１％（Ｐ＜０．０１），影响增重峰期为感染后第１～１０和２１～４０天；感染同量异刺线虫卵雏鸡成活率低１０．３％（Ｐ＞０．０５），死亡主因是组织滴虫病，增重低１６．６％（Ｐ＜０．０５），影响增重峰期在感染后第１１～２０天，混合感染减半量的两种虫卵，成活率低１４％（Ｐ＜０．０５），增重低３２．９％（Ｐ＜０．０１），死亡及发育受阻期与单独感染蛔虫卵组相似，但部分鸡死于组织滴虫病；单独感染减半量蛔虫卵，成活率低１７．３％（Ｐ＜０．０５），增重低１０．１％（Ｐ＞０．０５），死亡及影响增重峰期基本在感染后第１～１０天。     

Protective effects of sugar cane extracts (SCE) on Eimeria tenella infection in chickens

The effects of oral administration of sugar cane extracts (SCE) on Eimeria tenella oocysts infection in chickens were studied with 2 different experiments. In Experiment 1, 3-week-old inbred chickens (MHC; H.B15) were inoculated into the crop with SCE (500 mg/kg/day) for 1 day or 3 consecutive days, and then challenged with E. tenella sporulated oocysts (2 x 10(4) cells/chicken). In Experiment 2, 1-week-old chickens were orally administered SCE at the same dose for 3 consecutive days, and then initially infected with E. tenella sporulated oocysts (2 x 10(3) cells/chicken). At 2 and 3 weeks of age, these chickens were immunized intravenously with the mixed antigens of sheep red blood cells (SRBC) and Brucella abortus (BA). At 4 weeks of age, chickens were challenged with E. tenella sporulated oocysts (1 x 10(5)/chicken). Challenged chickens with E. tenella oocysts showed markedly decreased body weight gain/day, severe hemorrhage and great number of shedding oocysts in feces and high lesion scores. Oral administration of SCE and initial infection with oocysts (2 x 10 (3)/chicken) resulted in a remarkable improvement in body weight gain/day, hemorrhage, the number of shedding oocysts and lesion score, compare to other infected groups. In addition, SCE-inoculated chickens with the initial infection showed a significant increase in antibody responses against SRBC and BA and also improvement in decreased relative proportions of Bu-1a(+) and CD4( )cells in cecal tonsil lymphocytes of E. tenella-challenged chickens. Cecal tissues of chickens administered SCE and initially infected with E. tenella oocysts showed lower numbers of schizonts, gametocytes and oocysts than those of infected control chickens. These results suggest that SCE have immunostimulating and protective effects against E. tenella infection in chickens.     

Experimental cryptosporidiosis and infectious bursal disease virus infection of specific-pathogen-free chickens

Specific-pathogen-free chickens orally inoculated at 4 days of age with a moderately pathogenic vaccine strain of infectious bursal disease virus (IBDV) and/or at 5 days of age with Cryptosporidium baileyi oocysts remained free of overt clinical signs throughout a 16-day period postinoculation (PI). The prepatency period for C. baileyi oocyst shedding was shorter in chickens receiving higher numbers of oocysts, but once shedding was detected, there were no obvious differences in shedding patterns among groups receiving 10(3) through 10(6) oocysts. On days 8 and 16 PI, cryptosporidia were located primarily in the bursae of Fabricius. IBDV exposure was associated with bursal follicle atrophy, whereas C. baileyi infection resulted in bursal epithelial hypertrophy and hyperplasia, mild follicle atrophy, and heterophil infiltration of the bursal mucosa. Examination of experimental groups of 30 birds each indicated that concurrent infection with both agents resulted in more severe bursal lesions, more infected birds, and greater numbers of cryptosporidia in infected tissues. At the termination of the trial, 16 days PI, Cryptosporidium infection was associated with a 6% decrease in mean body weight compared with controls.     

Effect of resinous extract from Commiphora swynnertonii (Burrt) on experimental coccidial infection in chickens

A crude resinous extract from Commiphora swynnertonii was tested against an experimental coccidial infection in local chickens. A total of 80 growing chickens were randomly assigned into five groups, which received different treatments. Chickens in G1 were not infected with coccidian oocysts and therefore served as a negative control. All chickens in G2, G3, G4 and G5 were infected through oral administration of coccidian oocysts suspension at a dosed rate of 1.5?×?10⁴ Eimeria spp. oocysts per bird. Starting from day 3 post-infection (p.i), chickens in different groups were treated for 7 consecutive days as follows: G1 and G2 (positive control) received 5 ml of normal saline as placebo, G3 and G4 were given the extract at 400 and 800 mg/kg bodyweight whereas G5 received anticoccidial drug. Clinical signs, bodyweights, oocysts counts and mortality rates were observed regularly. Results showed that oral administration of the resinous extract to chickens with coccidiosis significantly reduced mortality rate from 94 to 25 % and oocysts counts from 1.03?×?10⁵ to 6.55?×?10³ oocysts/g faeces (p?<?0.05). Also a body condition score chart indicated less severe clinical signs of the disease in the groups which received the extract. Mean daily body weights were slightly reduced by the administration of the extract but this effect disappeared by day 7 p.i. These findings clearly indicate that resinous extract from C. swynnertonii has significant anticoccidial effect against experimental Eimeria spp. infection in chickens. A larger field trial to validate the use of the extract in chickens naturally infected with Eimeria spp. is required.     

Performance and oocyst shedding in broiler chickens orally infected with Cryptosporidium baileyi and Cryptosporidium meleagridis

To study effects of experimental cryptosporidiosis, broiler chickens were infected per os with 5 x 10(5) oocysts of Cryptosporidium baileyi and Cryptosporidium meleagridis. In the first experiment, chickens were infected with oocysts of C. baileyi at the age of 7, 14, and 21 days. In the second experiment, chickens were infected with oocysts of C. baileyi, C. meleagridis, or both cryptosporidial species at the age of 7 days. Although clinical signs of infection were apparent, neither final live weight nor mortality was significanty influenced in chickens infected with a single Cryptosporidium species. In chickens infected with C. meleagridis, the growth retardation was observed in the 2-wk period after infection. The compensatory growth, however, started when the oocyst shedding had ceased. The number of oocysts in excreta specimens of chickens infected with C. meleagridis was two to three times lower than in excreta of chickens infected with C. baileyi. Chickens infected with both C. baileyi and C. meleagridis (5 x 10(5) oocysts of each) had significantly lower final live weight and worse feed efficiency than chickens of other groups. Concurrent infection did not influence individual C. baileyi or C. meleagridis oocyst shedding.     

Effect of ibuprofen on coccidiosis in broiler chickens

Ibuprofen (IBU)-a nonsteroidal anti-inflammatory drug-inhibits the biosynthesis of prostaglandins with pro-inflammatory and immunosuppressive properties and is therefore proposed as a candidate molecule for the treatment of coccidiosis in broiler chickens. In all experiments, IBU was administered via drinking water. In a first experiment, chickens were infected at 10 or 21 days of age with oocysts of Eimeria acervulina (5 X 10(4)), Eimeria maxima (3 X 10(4)), and Eimeria tenella (7.5 X 10(3)) and medicated with IBU at a dose of 15 mg/kg body weight (BW). In a second experiment, chickens were infected at 6 days of age with 10(4) oocysts of E. acervulina and medicated with IBU at a dose of 100 mg/kg BW. In the third experiment, an inoculum consisting of 5 x 10(4) or 10(5) E. acervulina oocysts was administered at 6 days of age to chickens medicated with IBU at a dose of 100 mg/kg BW. In a fourth experiment, the effect of IBU on sporulation and infectivity of E. acervulina oocysts was studied. Coccidial lesion scores (CLSs), oocyst shedding, and weight gain were used as evaluation parameters in all experiments except the fourth, where weight gain was not taken into account. In addition, the sporulation percentage was determined in the last experiment. No influence of IBU on the indicated parameters was observed after providing the drug at a dose of 15 mg/kg BW, whereas CLSs and oocyst shedding were reduced when IBU was provided at a dose of 100 mg/kg BW. However, IBU did not significantly show any effect on the degree of sporulation and infectivity of E. acervulina oocysts at a dose of 100 mg/kg BW.     

Effect of avilamycin, tylosin and ionophore anticoccidials on Clostridium perfringens enterotoxaemia in chickens

In order to study the prophylactic and metaphylactic effect of antomicrobial growth promoters and ionophorous anticoccidials on the incidence of Cl. perfringens enterotoxaemia in chickens, experimental attempts were performed with 675 chickens in 27 trials. The birds were intraduodenally infected with Cl. perfringens type A (ATCC 3624). The following antimicrobial growth promoters and ionophore anticoccidials were used either on their own or in combination: avilamycin, narasin, monensin and tylosin. While infected and non-medicated trials showed an average incubation period of 1 week, clinical symptoms occurred 2-4 days later in infected and medicated birds. Avilamycin medicated birds had the longest incubation period. In the infected and non-medicated trials, a mortality rate of 16%-36% was noted within 3 weeks post infection. The avilamycin trials showed a mortality rate of 0-8% (0-2 birds died) and the narasin and monensin a mortality rate of 0-8%, respectively. In the combination groups (monensin + avilamycin or narasin + avilamycin), the mortality rate ranged from 0 to 4%. Tylosin showed a very good metaphylactic/therapeutic effect against Cl. perfringens enterotoxaemia. Following infection, medicated birds showed a significantly better bodyweight gain than the chickens, whose feeds had not been supplemented. From epidemiological point of view, the systematic prevention of coccidiosis is a key in the control of Cl. perfringens enterotoxaemia in chickens.     

Prevalence of Cryptosporidium parvum infection and pattern of oocyst shedding in calves in Japan

Cryptosporidium parvum infection and the pattern of oocyst shedding were observed in calves. A total of 480 fecal samples were collected from 30 calves (age, < or =30 days) over a period of 10 months from June 1998 to March 1999. A sucrose centrifugal flotation technique revealed 28/30 (93%) calves were passing Cryptosporidium oocysts. Oocyst shedding was first detected on the sixth day after birth, with 8% of the calves testing positive. This rate increased day by day and reached approximately 80% by day 15. Oocyst shedding varied from 1 to 13 days, with a mean of 7 days. Calves infected with C. parvum had a significantly higher rate of diarrhea (33%) than non-infected calves (8%) (P<0.05), suggesting C. parvum infection as the likely cause. The mean number of oocysts excreted by calves < or =30 days old was approximately 6x10(7) per gram of feces. These results indicated that one calf would excrete some 6x10(11) oocysts in the first month after birth, taking both the quantity of feces in a day and the period of excretion into consideration. Accordingly, it is clear that calves are important in the spread of cryptosporidiosis to calves and humans.     

Immunization of young chickens by trickle infection with Eimeria tenella.

Immunization of chickens was attempted with low levels of Eimeria tenella oocysts (50 oocysts per day) over the first 1 or 2 weeks of life--the "trickle infection" (TI) method. When chickens were immunized by TI at 0-13 days of age, no cecal lesions and a reduced number of oocysts in ceca were observed after challenge at 17 days of age. TI at 0-6 days of age conferred better protection against challenge with E. tenella than did TI at 7-13 days. However, cecal lesions were observed in almost all of these chickens. These findings indicated that TI for 2 weeks (0-13 days of age) provided better immunity than TI for 1 week (0-6 or 7-13 days of age).     

Effects of clopidol on sporulation and infectivity of Eimeria tenella oocysts

Feed additive anticoccidials currently used in Japan were examined for possible effects on oocyst sporulation of Eimeria tenella. Monensin, salinomycin, lasalocid, amprolium plus ethpabate, amporolium plus ethopabate plus sulfaquinoxaline, clopidol, or nicarbazin were given to chickens continuously via the feed at the recommended use level or one-half of that level. Oocysts discharged in feces 7-8 days post inoculation (PI) were collected and aerated for sporulation. Low sporulation rate was noted, when clopidol at 62.5 mg kg-1 was given from 4 to 7 days PI. These oocysts were as infective as oocysts from controls, based on weight gain, feed efficiency, gross lesion score of cecae, and oocyst count 7 days PI. The results of the study indicated that the second schizogony and gametogony are vulnerable to clopidol, as evidenced by oocyst sporulation, but infectivity of these sporulated oocysts was not affected.     

Gallid-1 herpesvirus infection in the chicken. 3. Reinvestigation of the pathogenesis of infectious laryngotracheitis in acute and early post-acute respiratory disease

Specific-pathogen-free chickens were infected via the trachea when 4 weeks old with 2000 plaque-forming units (PFU) of the virulent Australian infectious laryngotracheitis (ILT) virus strain CSW-1. Titers of ILT virus in the trachea were greatest (10(7.0) PFU/ml in washings, 10(6.0) PFU/g of tissue) 2-4 days postinfection (PI). Infectivity then declined rapidly, to become undetectable by 7 days PI, although highly localized areas of ILT antigen in the tracheal epithelium were occasionally observed by fluorescent antibody staining at 7 and 8 days PI. Tracheal organ cultures established 7 and 8 days PI provided no evidence of latent ILT virus infection at this immediate post-acute stage of pathogenesis. ILT virus was not isolated from peripheral blood leukocytes or lymphoid organs (spleen, bursa, thymus). ILT virus was found in the trigeminal ganglia and/or brain in 14 of 36 chickens (40%) examined between 4 and 7 days after intratracheal inoculation, but it was not in these tissues in five chickens examined at 8 days PI. Virus was also detected at 6 days PI in the trigeminal ganglia in one of five chickens infected by the conjunctival route. These data indicate that the early pathogenesis of ILT (CSW-1) infection frequently involves the tissues of the nervous system. In acute ILT in 4-week-old chickens, interferon-alpha/beta activity was not detectable in serum or tracheal exudates within 14 days PI, but tracheal washings contained significant virus-neutralizing activity by 7 and 8 days PI. In 3-day-old chickens infected via the trachea with 200 PFU of ILT CSW-1, the clearance of ILT virus from the trachea was similar to that observed in 4-week-old chickens, but ILT virus spread systemically to the livers of 20% by 5-7 days PI.