Protection of lambs against tetanus

Extract

Although all domestic animals, apart from birds, are susceptitble to tetanus, the disease in New Zealand is seen most commonly in young lambs. Neonatal infection has been suspected in the field, but postive confirmation of a clinical diagnosis is difficult. The most serious outbreaks occur shortly after docking, especially where the yard hygiene is poor or when docking methods result in slow healing of tail wounds.     

Immunization against cholecystokinin decreases appetite in lambs.

The effects of immunization against cholecystokinin (CCK) on feed intake, weight gain, and carcass characteristics were studied in sheep. Nine wether lambs at 10 wk of age were immunized with a conjugate of sulphated CCK octapeptide and human serum globulin or against human globulin alone. All CCK-immunized lambs produced antibodies, and the average titer 5 wk after the primary immunization was calculated to be sufficient to bind normal circulating levels of CCK. Mean daily feed intakes and BW were similar in the CCK-immunized and the control-immunized groups at the start of treatment, but after immunization, feed intake, appetite, and BW gain were decreased in the CCK-immunized animals. There was no effect on carcass composition or organ growth relative to body growth. It is concluded that the immunization procedure used in this study may have potentiated the actions of CCK rather than neutralizing its action as an appetite regulator.     

Immunization with irradiated larvae against Dictyocaulus filaria in young lambs

In the lungworm-endemic areas of Kashmir, 6-10 week old lambs of Karnah and Kashmir Merino breeds were vaccinated with two doses of 50 kR gamma-irradiated larvae of Dictyocaulus filaria, given a month apart. Assessed on the basis of reduced prevalence and significantly lower faecal larval output over an eight-month observation period, vaccinated lambs showed a high degree of resistance to naturally acquired D. filaria infection. The results also show that vaccination against D. filaria provided some degree of protection against infection with other lungworm species.     

Immunization protocols against Cryptosporidium parvum in ovines: protection in suckling lambs

Ovine colostrum and milk from immunized ewes were tested for their ability to prevent cryptosporidiosis in the lambs experimentally infected with 10(6) oocysts of Cryptosporidium parvum at 36-48 h of age (day 0 post-infection). All lambs became infected and developed clinical cryptosporidiosis. However, lambs fed by immunized dams have shown shedding involved, significantly, fewer oocysts and lasted for a shorter period than in control lambs. In addition, diarrhoea was less severe. The best results emerged in lambs of ewes immunized by intramuscular injection of an emulsion of 2 ml of Freund's complete adjuvant and 2 ml of C. parvum antigen in sterile phosphate buffered saline solution, administrated four weeks before parturition, together with an intramammary infusion of 25 microg of antigen in 2 ml of sterile PBS emulsified in 2 ml of Freund's incomplete adjuvant, which showed the highest anti-C. parvum titres in lacteal secretions. In their case, the onset of output of oocysts was delayed by two days, the patent period was shortened by three days, their diarrhoea continued for only three days, and the quantity of oocysts shed decreased by 77%. The outcome was that at the end of the study they had a live weight gain of 2 kg more than the lambs in the control group. These results indicate that lactogenic immunoprophylaxis should help mitigate the financial losses caused by cryptosporidiosis in small ruminants, as well as reducing the risk of infection of humans through the decreased contamination of the environment with oocysts.     

Comparison of oil adjuvant and aluminium phosphate-adsorbed toxoid for the passive immunization of lambs against tetanus

Immunization of ewes with oil emulsion toxoid followed by an aluminium phosphate-adsorbed toxoid both containing 10 Lf per dose, resulted in a very high antitoxin level in their lambs. Two injections of aluminium phosphate-adsorbed toxoid also imparted a passive immunity to lambs which is considered to be adequate to protect them against tetanus for 4 weeks after birth.     

一例种公牛急性肾炎的诊治

2005年5月6日,我市某农户饲养的一头3岁种公牛突然发病,从5日开始不食,精神不好,注射抗生素后不见好转,来我兽医院就诊。根据发病情况、临床症状及尿液检查,确诊为急性肾炎。现将我兽医院对该病例的诊疗情况报告如下。1病史经询问得知,该种公牛4日依然正常,还与邻家进行过1次配     

新生羔羊要防破伤风

新生羔羊破伤风又名脐风、四六风，是因用未消毒的剪刀剪脐带或用不清洁的线解扎脐带，使破伤风杆菌通过脐部感染所致。破伤风杆菌是一种厌氧菌，存在于泥土、粪便中。如果不搞好羊圈舍的环境卫生及消毒灭菌工作，加上一些养殖户给羊接生时，对羔羊脐部不进行认真消毒和结扎，均可造成破伤风杆菌感染而发病。     

Immunization against psittacine pox

Pox virus isolated from psittacine birds was used as a vaccine in trials with love birds (Agapornis roseicollis). The vaccine was applied by wing-web puncture using single- and double-needle applicators. Immunity was effective against challenge with virulent psittacine pox virus administered via the feather follicle/thigh. When unvaccinated contact control birds were placed with the vaccinated individuals immediately post-vaccination, virus spread was evident. However, susceptible birds placed with vaccinated ones at 27 days postvaccination remained uninfected for 11 weeks. The importance of a high vaccine virus titer was observed.     

Immunization of neonatal lambs against the larvae of Taenia hydatigena, using viable eggs followed by chemotherapy

The subcutaneous injection of viable eggs of Taenia hydatigena into neonatal lambs induced 100% protection against the development of viable T. hydatigena larvae from an oral challenge. However, contrary to some published results, no protection was induced against a simultaneous infection with eggs of T. ovis and Echinococcus granulosus.The short-acting partial resistance to oral infection with T. hydatigena eggs, transferred from infected ewes to their lambs, was not enhanced by hyperimmunization of the ewe. In the lamb, this resistance did not interfere with the development of subcutaneously injected T. hydatigena eggs into immature larvae, or with the consequent induction of resistance to an oral challenge with T. hydatigena eggs. The immunizing lesion regressed rapidly after treatment of lambs with Mebendazole, and after 6 months the lesions were negligible in both treated and untreated lambs.