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101.
Present electron microscopical and immunocytochemistrical studies elucidated some morphological relationship between intercalated duct (ICD) and pancreatic islet cells in the chicken in streptozotocin (STZ) and/or camostat mesilate (CM) administrations. Twenty-one chickens were set into four experimental groups: (1) control group, (2) STZ administration group, (3) CM administration group, and (4) STZ + CM administration group. Cytoplasms of ICD cells stained more strongly with eosin in STZ administration group than other groups, and electron-dense materials and intercalated processes between ICD and islet cells were also increasing in time dependence in STZ administration. Number of pancreatic islet in STZ + CM co-administration was about 3.1 times larger than other groups. Many small sized cells were detected at surrounding area of ICD and they incorporated 5-bromo-2'-deoxyuridine better than other experimental groups. Present morphological data suggested that ICD cells might support some tolerances of pancreatic endocrine cells against toxic substances and also involve in regeneration of new pancreatic islet cells in STZ + CM co-administration.  相似文献   
102.
1. The relationship between breeder age and chick gastrointestinal tract development to 21 days of age, as influenced by immediate or delayed access to feed, was examined in three consecutive trials.

2. Ross 708 chicks, derived from breeder flocks at 31 (young), 40 (middle) and 63 (old) weeks of age were placed randomly into either a control group with immediate access to feed and water, or a 48?h feed delayed (FD) group with free access to water.

3. FD negatively affected body weight (BW) of chicks derived from young and old flocks through the first and second weeks of age, respectively. Chicks from the older flock absorbed more yolk in the first 48?h with no FD effect. When feed was made available, chicks from the FD group showed a large increase in small intestine weight relative to BW, surpassing (P? 4. Morphological measurements in all intestinal sections had higher values in chicks derived from the middle age breeder flock. FD to newly hatched chicks from the young breeder flock shortened villi (P?P? 5. Crypt depths were maximised between 7 and 14?d post-hatch in chicks from young and old breeder flocks, but crypt depths in chicks from the middle aged flocks continued to deepen.

6. The increased crypt depth may augment the number of enterocytes available for villus growth, and facilitate longer villi and greater villus surface area, in chicks from the middle age flocks. Intestinal morphological variation was associated with breeder flock age, which accounted for differential growth in chicks derived from young, middle, and old aged breeder flocks.  相似文献   
103.
104.
A previously unreported pancreatic duct was found by Liu (1989) in Pekin ducks. This duct has now been consistently found in six breeds of domestic ducks and six species of wild ducks in China. For purposes of Nomina Anatomica Avium it is hereby called the ‘first pancreatic duct’(Ducius pancreaticus primus) since it enters the duodenum at or near the flexure where the descending duodenum becomes the ascending duodenum. All other pancreatic ducts enter the duodenum later, closer to where it joins the jejunum. This first pancreatic duct drains the caudal extremity of the dorsal lobe of the pancreas and can be easily exteriorized for experimental purposes. Within the parenchyma of the dorsal lobe of the pancreas this duct communicates with the dorsal pancreatic duct. In the present study of the gross anatomy of the pancreatic lobes of domestic and wild Chinese ducks we describe and illustrate variations in position and number of all biliary and pancreatic ducts.  相似文献   
105.
106.
According to two properties of the life cycle and to fluctuation with parities, four mathematical models, the Poisson cycle model, the cubic polynomial model, the modified quadratic polynomial model-I and the modified quadratic polynomial model-II, were used to fit the records of litter size in Jiangquhai sows. From the viewpoint of statistics and biological significance, the modified quadratic polynomial model-I was found to be the optimum model. A single trait animal model and DFREML procedures were further used to estimate the heritability values of optimum model parameters. The results show that the heritability values for the coefficients A and B and the heritability value for the acme of the model pure quadric curve are larger than the heritability value for the litter size. This suggests that selection for model parameters may be more effective than direct selection for litter size.  相似文献   
107.
The macroscopic features of the arterial supply to the reproductive system of the male ostrich was studied in 16 pre-pubertal and eight sexually mature and active birds. The left and right cranial renal arteries arise from the aorta, between the cranial divisions of the kidneys. These vessels supply the cranial divisions of the kidneys, the testes, the epididymides and the cranial segments of the ducti deferentia. Accessory testicular arteries which arise directly from the aorta are present in 45.8% of the specimens. They supply the testes and cranial parts of the ducti deferentia. They are variable in number and origin, and four variants are identified. A cranial ureterodeferential branch originates from the cranial renal artery, supplies the cranial portion of the ductus deferens and ureter, and runs caudally to anastomose with the middle renal artery. The sciatic artery arises laterally from the aorta, just caudal to the acetabulum, and gives rise, ventrally, to a common trunk, the common renal artery, which divides into the middle and caudal renal arteries. The middle renal artery gives rise to the middle ureterodeferential branch which supplies the middle part of the ductus deferens and ureter. A few centimetres caudal to the kidney, the aorta terminates in three branches, namely, the left and right internal iliac arteries and the median caudal artery. The internal iliac artery divides into the lateral caudal artery and the pudendal artery; the latter gives off caudal ureterodeferential branches that supply the caudal segments of the ductus deferens and ureter. In addition, the pudendal artery gives off vessels that supply the cloaca, some of which continue to the base of the phallus, where they form an arterial network. In conclusion, the pattern of the blood supply to the reproductive organs of the male ostrich is, in general, similar to that of the domestic fowl and pigeon, although there are a few highlighted distinctive features.  相似文献   
108.
109.
Summary Uncooked white rice and cooked white rice were tested as vehicles for the V4 strain of oral Newcastle disease vaccine. The results of feeding experiments were evaluated by the measurement of haemagglutination inhibition antibodies against Newcastle disease virus. Little of the virus applied to uncooked white rice could be recovered, even immediately after mixing, whereas when the virus was applied to cooked white rice most of it could be recovered. In 4 separate experiments, chickens failed to respond serologically to vaccine supplied on uncooked white rice. In all of 4 experiments with cooked white rice, there were serological responses in vaccinated chickens, from 45% to 100% of the chickens developing titres sufficiently high to indicate protection against challenge with virulent virus. Development of haemagglutination inhibition antibodies in some control chickens indicated the ability of the vaccine virus for lateral spread or persistence in the environment.
Vacunacion Oral De Pollos Con La Cepa V4 Del Virus De La Enfermedad De Newcastle Utilizando Como Vehiculo Arroz Blanco Cocinado Y No Cocinado
Resumen Se utilizo arroz blanco sin cocinar y cocinado como vehículo para la vacuna oral con la cepa V4 de la enfermedad de Newcastle. Los resultados de los experimentos fueron evaluados mediante la determinación de los anticuerpos de inhibición-hemaglutinación contra el virus de la enfermedad de Newcastle. Poca cantidad del virus de la enfermedad de Newcastle pudo recuperarse en el arroz crudo, incluso inmediatamente despues de revolverlo, mientras que la mayoría del virus pudo recuperarse del arroz cocinado. En 4 experimentos separados, los pollos no respondieron serológicamente a la vacuna aplicada en arroz blanco crudo. En los 4 experimentos con arroz cocinado, se detectaron respuestas serológicas en los pollos vacunados; 45% a 100% de los pollos desarrollaron títulos suficientes como para resistir la descarga de virus virulento. El desarrollo de anticuerpos de inhibición-hemaglutinación en algunos de los pollos controles indicó la capacidad del virus vacunal para dispersarse lateralmente y persistir en el ambiente.

Vaccination Par Voie Orale De Poulets Avec La Souche V4 Du Virus De La Maladie De Newcastle Avec Comme Support Du Riz Blanc Cuit Et Du Riz Blanc Cru
Résumé Du riz blanc crû et du riz blanc cuit ont été testés en tant que supports de la souche de virus V4 du vaccin contre la maladie de Newcastle. Les résultats de ces expériences d'alimentation ont été évalués par la mesure des anticorps d'inhibition de l'hémagglutination du virus de la maladie de Newcastle.Seule une petite quantité du virus mélangé dans le riz blanc crû a pu être récupérée même immédiatement après le mélange. Par contre la majeur partie du virus a pu être récupérée lorsqu'il s'agissait du riz blanc cuit.Dans 4 expériences séparées, ils n'y avait pas de réponses sérologiques chez les poulets recevant du vaccin ajouté au riz blanc crû. Dans toutes les 4 expériences avec du riz blanc cuit, les réponses sérologiques ont été positives chez les poulets vaccines, 45p. 100 à 100p. 100 des poulets développant des titres suffisamment élevés pour démontrer une protection contre l'épreuve avec du virus virulent. Le développement des anticorps d'inhibition de l'hémagglutination chez quelques poulets témoins a montré la capacité de diffusion latérale ou la persistance dans l'environnement du virus.
  相似文献   
110.
Tropical Animal Health and Production - This study aimed to verify the reproductive seasonality in Saanen goats from distinct parity orders (nulliparous, primiparous, and pluriparous) throughout an...  相似文献   
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