Controlled early feed restriction as a potential means of reducing the incidence of ascites in broilers.

Male broiler chicks were grown at cold temperatures to enhance susceptibility to the ascites syndrome. Various feeding regimens were used to determine whether they could influence mortality due to ascites. It was found that a precisely controlled early feed-restriction regimen at the age of 6 to 11 days significantly reduced mortality from all causes and mortality due to ascites, while maintaining optimum body weight and feed conversion at marketing age.

The role of 17 beta-estradiol in the recovery from oviductal prolapse in layers.

Plasma 17 beta-estradiol concentrations, thecal estrogen content, and uterine prostaglandin synthetase activity were measured in healthy and prolapsed hens as well as in layers that recovered after exposure to low intensity lighting (250 or 50 lx). The effect of estradiol benzoate injections (100 ng, 3 X per week) in hens exposed to high intensity light (greater than 500 lx) was also studied. Prolapsed hens had significantly lower plasma 17 beta-estradiol concentrations (60 +/- 12 pg/ml; mean +/- SEM) than recovered (374 +/- 40 pg/ml) or healthy hens (475 +/- 45 pg/ml). Theca cells from recovered hens had a significantly higher content of 17 beta-estradiol (.7 ng/5 X 10(5) cells) than theca cells from normal or prolapsed birds (.3 ng/5 X 10(5) cells). Microsomes prepared from the uteri of prolapsed hens converted significantly less arachidonic acid to prostaglandin metabolites (4.4%) than did microsomes from healthy or recovered birds (9.0%). Treatment of prolapsed hens with estradiol benzoate resulted in 89% of the birds recovering within 3 weeks compared to a 4% recovery rate in the controls. We conclude that restoration of peripheral 17 beta-estradiol concentrations to normal levels was concomitant with recovery in prolapsed birds, and suggest that the estrogen exerts its effect by raising the level of prostaglandin synthetase activity in the uterus.

[On the development of carcasses disposal in Israel paying particular attention to the industrial slaughtering of poultry (author's transl)]. / Uber die Entwicklung der Tierkörperbeseitigung in Israel mit besonderer Berücksichtigung der industriellen Geflügelschlachtung.

Although a regulation has been in force in Israel since 1930 which committed the communities to provide for knackers' yards, until some years ago packs of jackals took care of the carcass disposal. Owing to the increase of large slaughter houses for fowl some rendering plants were also erected, which however, eliminated only the waste from these plants. For this reason the government decided to build rendering plants on the European pattern and to legislate pertinent veterinary acts. In Israel 20,000 tons fish-meal is imported annually, worth millions of dollars for feeding purposes, while no attention is as yet being paid to the processing of the national raw materials.

The effects of poor ventilation, low temperatures, type of feed and sex of bird on the development of ascites in broilers. production parameters.

The effects of type of feed, ambient temperature and ventilation on ascites were investigated on a fast-growing strain of broiler with regard to production parameters. It was found that poor ventilation had no effect on the incidence of ascites. Pelleted feed, when compared with the same feed in a mash form, induced a higher incidence of mortality with ascites. Of all these factors, exposure to cold temperatures was the most potent inducer of ascites. For the short-term control of the ascites syndrome, these aspects of husbandry can be changed by the grower to minimalize losses.

Viral aetiology of haemangiosarcoma outbreaks among layer hens.

Outbreaks of neoplastic disease defined as haemangiosarcoma occurred among layer flocks of chickens in Israel. The disease caused bleeding tumours in the skin and internal organs of young layers, followed by anaemia, cessation of egg production and high mortality up to 20%. Avian leukosis virus was isolated from tumour cells which contain several viral DNA copies integrated in the cell genome. The isolated virus induced haemangiosarcomas in more than 30% of birds inoculated on the day of hatching. Congenital transmission of viruses from tumour-bearing hens to their offspring was observed.

The occurrence of the tropical bedbug (Cimex hemipterus, Fabricius) in poultry barns in Israel.

The occurrence of the tropical bedbug (Cimex hemipterus Fabricius) in poultry houses in Israel is described. Despite the heavy infestation serious losses have not been registered and no clinical signs observed. Treatment of the barns and accessories with 2% malathion emulsion gave good results. The parasite invaded human habitations as well.

The effects of poor ventilation, low temperatures, type of feed and sex of bird on the development of ascites in broilers. physiopathological factors.

The effects of type of feed, ambient temperature and ventilation were investigated on a fast-growing strain of broiler under conditions conducive to the induction of the ascites syndrome. Parameters used to monitor the syndrome were the erythrocyte packed cell volume (PCV), and the ascites heart index (AHI) which is a measure of the hypertrophy of the right ventricle; both these parameters are elevated in birds suffering from the syndrome. It was found that ventilation had no role in the syndrome. Sex of the bird was not correlated with PCV or AHI values. Low ambient temperatures caused rapid and significant rises in PCV, and some rise in the AHI. Pelleted feed, in comparison with the same feed in mash form, was shown to cause significant elevations in the AHI, but little change in the PCV. Suitable husbandry can therefore, minimize physiopathological changes in the chickens which may later progress to a fatal ascites.

Maternal immunization with gametocyte antigens as a means of providing protective immunity against Eimeria maxima in chickens.

In the present study, we wished to demonstrate the ability of surface gametocyte antigens to induce protective immunity against Eimeria maxima infections in chickens. In order to accomplish this goal, we employed maternal immunization as a means of providing large amounts of specific antibodies to offspring chicks. Upon challenge with sporulated E. maxima oocysts, chicks from hens immunized with affinity-purified gametocyte antigens showed greatly reduced oocyst production compared with chicks from sham-immunized hens. These results suggest that maternal immunization with gametocyte antigens can be used as a means to provide transmission-blocking immunity against E. maxima infections.