Biomedical subjects

P Gazdzinski

Publications and source records attributed to P Gazdzinski.

5 recordsLinked to original sources

PubMed1998

Differentiating between parthenogenetic and "positive development" embryos in turkeys by molecular sexing.

In mated or inseminated turkeys, 5 to 15% of eggs set for incubation show only rudimentary development. Most of these embryos die during the first 24 to 48 h of incubation and contain only unorganized sheets of tissue. This abnormal development is termed "positive development" (PD). Turkey eggs also show incidence of parthenogenesis and the resulting progeny is believed to be always male. As both types of embryos are morphologically similar at the early stage of incubation, it has been speculated that PD embryos may in fact be parthenogens. By identifying the sex at the blastodermal stage with the help of DNA markers, we have differentiated between the PD embryos and parthenogens. Parthenogenetic embryos were obtained from eggs laid by uninseminated or virgin Beltsville Small White (BSW) hens, and the PD embryos were obtained from eggs of inseminated Nicholas and British United Turkeys of America (BUTA) hens. DNA was extracted from blastoderms of parthenogenetic and PD embryos. Turkey W-chromosome specific DNA probe and primers were used to detect females in all samples by Southern blot and polymerase chain reaction (PCR), respectively. No female was detected among the 35 parthenogens examined, whereas there were 3 females among the 11 PD embryos. The presence of both males and females among PD embryos suggests that they are products of fertilization, and that at least these 3 female embryos, if not all the 11 PD embryos, are not of parthenogenetic origin. It is concluded, therefore, that PD embryos result from errors in fertilization or from early embryonic mortality following successful fertilization, and that they are unlikely to be of parthenogenetic origin.

Animals↗

PubMedDate not supplied

Virulence of recent isolates of Mycoplasma synoviae in turkeys.

Systemic Mycoplasma synoviae (MS) infection was induced experimentally in commercial turkeys with recent MS isolates (K4822D and K4774J) from turkey breeder flocks that exhibited no clinical signs typical of MS infection except for a low incidence of swollen footpads. The virulence of each strain was compared by evaluating gross and microscopic lesions, serologic responses, and MS isolation rates at 10 and 21 days postchallenge and by comparing these results with those obtained from a known virulent isolate (K1968), another previously characterized field isolate (K4463B), and unchallenged controls. All strains induced lesions typical of infectious synovitis but showed distinct differences in the extent of the gross and microscopic lesions and in the isolation rates from the tissues in turkeys. K1968 induced the most extensive lesions in hock and stifle joints and footpads, but strains K4822D, K4774J, and K4463B all induced synovitis and were similar in virulence for synovial tissues. Very mild respiratory lesions were induced by all of the strains studied. All strains yielded strong positive serologic responses. We concluded that these recent field isolates, although able to induce synovitis, are less virulent for turkeys than a known virulent strain. Nevertheless, under severe experimental challenge, these strains have the capability of causing lesions that may be incompatible with economical turkey production.

Agglutination Tests↗

PubMedDate not supplied

Necrotic enteritis in turkeys.

Three flocks of turkey hens (16,000 each) between 7 and 12 weeks of age experienced outbreaks of necrotic enteritis. Necropsy revealed a dilated duodenum and jejunum with mucosal surfaces covered with a diphtheritic membrane. Intestinal scrapings showed very few oocysts of Eimeria sp. Histopathological findings were compatible with necrotic enteritis but with deeper, more severe lesions than in broiler chickens. Clostridium perfringens was isolated by anaerobic culture from the intestinal contents. Mortality returned to normal after ampicillin or tetracycline was added to the drinking water.

Animals↗

PubMedDate not supplied

Hepatic lipidosis in turkeys.

Two flocks of 14,000 twenty-week-old turkey hens each experienced increased mortality due to hepatic lipidosis. Some hens showed signs of dyspnea and cyanosis before death. Necropsy revealed dark muscles and enlarged livers with pale areas and numerous hemorrhages. Petechial and ecchymotic hemorrhages were also found on the abdominal fat and epicardium. Lung congestion and edema were prominent. In the heart and blood vessels, the blood was uncoagulated. Mortality was elevated for 12 days and resulted in the death of 0.7% of the turkey hens in one flock and 1.7% in the other. Vitamin E administered in water at a dose of 25 IU per hen appeared to reduce mortality. The nutritional and environmental factors that may contribute to the development of hepatic lipidosis in turkeys are discussed.

Animals↗

PubMedDate not supplied

The relation of egg specific gravity to the incidence of spontaneous cardiomyopathy in tom turkeys.

The specific gravity and weight of eggs were determined for two groups of 600 eggs each, originating from Nicholas and British United Turkey of America (BUTA) turkey breeder flocks. A total of 137 Nicholas and 190 BUTA toms hatched from these eggs were used for the experiment. At days 21, 33, 40, 47, 56, and 61, toms that showed retarded growth were euthanatized, along with a corresponding number of normal birds. Both groups were measured for body weight, heart weight, separate weights of left and right ventricles, and combined atrial weight. At market age, the remaining toms were weighed, and the hearts were checked at processing for lesions characteristic of spontaneous turkey cardiomyopathy (STC). STC was found in 10.2% of Nicholas and 8.4% of BUTA toms. No correlation could be found between specific gravity of eggs and incidence of STC. Body weights of affected toms were reduced during the growing period. At processing, 2.8% of toms had lesions of STC, and mean body weight was 1298 g lower than average. The ratios of combined atrial weight:body weight, right ventricular weight:body weight, left ventricular weight:body weight, and total heart:body weight were significantly higher at all times in affected toms than in controls, and the differences were the greatest at 3 weeks of age.

Animals↗