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1.
The growth and development of the metacercariae of F. seoulensis cultivated in vitro or on the chick chorioallantois were assessed by comparison with the optimum process of maturation in albino rats and new born chickens. The process of maturation was divided for convenience into six stages: Stage 1; cell multiplication, Stage 2; body shaping, Stage 3; separation of genital anlagen, Stage 4; organogeny, Stage 5; gametogony, and Stage 6; oviposition. In Hank's and Tyrode's solutions, the metacercariae were alive up to 200 days or more at 4 degrees C without any development. The in vivo maturation process in rats or chicks was as follows: stage 1 from 6 hours; stage 2 from 24 hours; stage 3 from 48 to 72 hours; stage 4 from 3 to 4 days; stage 5 from 4 to 5 days; and stage 6 from 5 to 8 days. Despite unsuccessful infection of the metacercariae to 12 day old chicks, fully mature worms of stage 5 or 6 were recovered from new born chicks (1 to 2 days old). The metacercariae of F. seoulensis grown in vitro were up to stage 3 and no further maturation was observed. Of various media employed, the medium NCTC 109 (Gibco) or NCTC 135 (Gibco) supplemented with 20% egg yolk or 20% whole egg macerate or 0.5% yeast was basically required for the earlier development of the fluke. It took 16.1 days (in average) to reach the stage 3 after cultivation. The metacercariae cultivated on the chorioallantoic membranes of 6-13 day old chick embryo at 37-38 degrees C showed their full development up to stage 5 or 6. However, the worms were in general remarkably retarded, compared with those grown in rats or chickens. In the experiments of worm transplant, although the transfer was failed from in vitro culture to in vivo of rats (per os), the transplants from in vitro culture to the chorioallantois and from the chorioallantois to in vivo of rat host were successful with or without development of the transferred worms. In the present study, it was observed that the metacercariae of F. seoulensis can be maintained in vitro media with poor development as well as fully matured in 1 to 2 day-old chicks or on the chorioallantois at a very low rate.  相似文献   

2.
The VR strain of avian encephalomyelitis virus, which had been adapted to embryonated hen's eggs, was inoculated into 2-day-old chicks by the subcutaneous route (10(2.5) approximately 10(3.0) EID50) or by the oral route (10(4.8) EID50). The chicks were examined chronologically for the distribution of the virus in the body. As a result, minute amounts of the virus were detected from the liver, spleen, pancreas, and muscle at the site of inoculation one day after inoculation and various amounts from almost all the organs 3 days and more after inoculation. The virus titer could nearly reach a maximum 7 to 9 days after inoculation. Above all, such high virus titers as ranging from 10(4.3) to 10(5.8) EID50/0.1 g were demonstrated in the brain, heart, liver, spleen, and pancreas. After that, there was a tendency for virus titer to decrease in most organs and for virus to multiply persistently in the pancreas, brain, and eyeball. Virus titer was maintained at a level of 10(2.3) approximately 10(2.8) EID50/0.1 g in these three organs even 21 days after inoculation. In the group of subcutaneous inoculation, all the chicks manifested clinical signs of infection 5 to 10 days after inoculation. On the other hand, no chicks were involved in clinical infection in the group of oral inoculation. Multiplication of the virus was delayed in the body of these chicks. Small amounts of the virus were detected from the spleen and pancreas 11 days after inoculation. Low titers (10(2.7) EID50/0.1 g at the highest) of the virus were only detected from the brain, spinal cord, spleen, pancreas, esophagus, and other organs 14 and 21 days after inoculation.  相似文献   

3.
1. Muscle and brain from developing chick embryos, as well as from day-old chicks, rats, and ducks were analyzed for the histidine-containing dipeptides, anserine and carnosine. 2. Anserine was found in the brain of all species studied, whereas in muscle, anserine was found only in chicks. 3. At 15 days, the muscle of developing chick embryo contained 41 +/- 9 mumoles/100 g anserine while carnosine was present at a level of less than 3 mumoles/100 g. 4. In day-old chicks the anserine level in muscle was 100 +/- 35 mumoles/100 g while the carnosine level was 22.5 +/- 1 mumoles/100 g. 5. These findings cast doubt on earlier hypotheses relating anserine and carnosine to muscle activity.  相似文献   

4.
A chick embryo-adapted strain of avian encephalomyelitis virus was inoculated subcutaneously and orally into 40-day-old (middle-aged) and 110-day-old (advanced-aged) chicks to examine the behavior of the virus in the chick body. In the middle-aged chicks, the virus appeared in the muscle at the site of inoculation, liver, spleen, pancreas, lumbar and cervical portions of the spinal cord, and brain 1 approximately 9 days after subcutaneous inoculation, and remained mostly in the central nervous system up to 17 days after the inoculation. The virus was found in large amounts in the muscle at the site of inoculation (10(3.1)), lumbar portion (10(2.5)) and cervical portion (10(2.1)) of the spinal cord, brain (10(1.9)), and in minute amounts in the other organs examined. It appeared in 11 of 21 organs examined. In the middle-aged chicks inoculated by the oral route, the virus was detected transiently in small amounts from esophagus, pancreas, and rectum 4 approximately 14 days after inoculation. In the advanced-aged chicks inoculated by the subcutaneous route, the virus was detected in titer of 10(2.1) approximately 10(3.0) from the muscle at the site of inoculation 2 approximately 7 days after inoculation. The virus was also found sporadically in several organs up to 17 days after inoculation. In the advanced-aged chicks inoculated by the oral route, no virus appeared in any organ, but these chicks turned to be weakly positive for neutralizing antibody in the 4th or later week after inoculation.  相似文献   

5.
Pathogenicity for chicks of the MSB-1 line, a cell line derived from the tumorous tissue of a chick with Marek's disease (MD) and established by Akiyama & Kato, was studied. Five groups, including a control one, of 20 chicks each were inoculated with 1 X 10(3), 1 X 10(4), 1 X 10(5), 1 X 10(6) and no cells of a 180-day culture of the cell line at one day of age. They were housed all together in an isolation unit. An attempt was first made successfully to isolate MD virus (MDV) directly in culture of kidney cells 3 weeks after inoculation. Horizontal infection was first detected 4 weeks after inoculation. From 3 weeks after inoculation on, the disease with almost the same clinical and pathological pictures as the infection with a virulent strain of MDV showed a high incidence. Morbidity was closely related to the number of MSB-1 line cells inoculated. Parenchymal destruction was conspicuous in the central lymphoid organs of four chicks given the largest number of MSB-1 line cells and sacrificed in extremis about 4 weeks after inoculation. Establishment of MD in chicks inoculated with MSB-1 line cells carrying MDV genome seemed to be initiated under the circumstances where the line cells which had come into contact with susceptible cells in the peritoneal cavity released virulent MDV per se. Then host chicks might be infected with MDV and suffer from MD at a high rate. There was no great difference in oncogenic potential between MSB-1 line cells cultivated in vitro for 180 days and virulent MDV serially passaged through one-day-old chicks.  相似文献   

6.
Growth and development of six hand-reared red bird of paradise chicks was documented at the New York Zoological Park from March 1988 to May 1989. A total of 16 eggs were laid, of which 10 were fertile. Clutches consisted of two eggs and the female left the next infrequently during incubation. Two chicks left in the nest were apparently victims of parental abuse. Eggs were subsequently removed from the nest after 10–14 days, candled, and if fertile, were artificially incubated. The average incubation period was 16.6 days. Newly hatched chicks were without down and their eyes remained closed until approximately 6 days of age. Hand-reared chicks were maintained in Air Shield Infant Isolettes. The weight of newly hatched chicks was about 8 g, and the weight typically doubled during the first week. Ratios of food intake to body weight were highest between day 4 and 10. Pin feathers were visible on the wings after 4 days, and after 3 weeks, the chicks were fully feathered. Analysis of the diet revealed acceptable levels of iron, but vitamin A and E levels were higher than recommended for poultry chicks. This paper documents the first successful hand-rearing of any species of birds of paradise from hatching to fledging.  相似文献   

7.
A single coronal slice, containing the intermediate part of the medial hyperstriatum ventrale (IMHV) was cut from the left forebrain of a series of domestic chicks and maintained in vitro. Records were made of field responses evoked in the IMHV by local electrical stimuli. Two 1-min periods of 5 Hz stimulation, separated by 10 min, were used in attempts to induce persistent potentiation of the responses (PPR) to test stimulation at 0.1 Hz. In dark-hatched chicks the probability of producing PPR is much higher in slices from chicks aged 2-5 days post-hatch than in those from either younger or older birds. As an independent measure of plasticity in dark-hatched chicks, the probability of eliciting unit responses to repeated stimulation of remote sites in the slice at 3.3 Hz was analysed. This probability was greater in slices from chicks aged 2-5 days than in those from either younger or older birds. In light-hatched chicks the probability of inducing PPR is significantly higher during the first day post-hatch, than in dark-hatched chicks of this age. The probability of producing PPR in slices from light-hatched chicks aged 2-3 days is less than that in slices from either younger or older birds. It is clear that both the age and past experience of the domestic chick affect the neurophysiological properties of slices of brain, tested in vitro.  相似文献   

8.
Chicks were experimentally infected with Acanthoparyphium tyosenense (Digenea: Echinostomatidae) metacercariae per os, and the growth and development of worms in this host were observed from days I to 38 postinfection (PI). The worms grew rapidly and matured sexually in the small intestine (chiefly in the jejunum) of chicks by day 5 PI. and survived at least up to day 38 Pi, although worm recovery decreased after day 5 PI. Both parenchymal and reproductive organs increased greatly in size from day 2 to day 10 PI and then continued to increase gradually in size up to day 38 PI. The number of uterine eggs reached a peak on days 10 and 15 PI and then decreased gradually. The results suggest that chicks are a fairly suitable definitive host for experimental infection with A. tyosenense.  相似文献   

9.
Neodiplostomula from the European grass snake Rhabdophis tigrina, in the Republic of Korea, were thought to represent 2 species: Pharyngostomum cordatum (large-sized neodiplostomula), an intestinal trematode of cats, and Neodiplostomum seoulense (small-sized neodiplostomula), an intestinal trematode of humans and rodents. The present study describes N. leei n. sp. (Digenea: Neodiplostomidae) on the basis of adult flukes recovered from the small intestines of chicks experimentally infected with small-sized neodiplostomula from the grass snake. The new species differs from N. seoulense in terms of the more extensive distribution of vitellaria, the more severe bilobation of 2 testes (each having a dumbbell shape), the absence of a genital cone, and the smaller size of the tribocytic organ and eggs. Neodiplostomula of the new species and N. seoulense are almost indistinguishable. The new species develops into an adult in chicks, whereas N. seoulense matures in mice and rats. Neodiplostomula of the new species migrate to the liver in mice and rats, without maturing. Results show that there are at least 3 species of neodiplostomid trematodes in the grass snake in the Republic of Korea, i.e.. P. cordatum, N. seoulense and N. leei n. sp.  相似文献   

10.
The presence of Marek's disease tumor-associated surface antigen (MATSA) was demonstrated by the direct and indirect membrane immunofluorescent tests, in chicks inoculated 7-10 days earlier with herpesvirus of turkeys (HVT), O1 strain. In in vitro cultures of spleen lymphocytes and ovaries obtained from these chicks, MATSA-positive cells were also detected after 1-7 days cultivation. A possible mechanism of protection by HVT vaccine against Marek's disease is proposed.  相似文献   

11.
Biosynthesis of phosphatidylcholine, phosphatidylethanolamine, and sphingomyelin was studied in liver endoplasmic reticulum obtained from newly hatched chicks which were made hypothyroid by feeding 0.2% propylthiouracil. In vitro measurements were made of the specific activities of phosphorylcholine-glyceride (cholinephosphotransferase (EC 2.7.8.2), hosphorylethanolamine-glyceride (ethanolamine-phosphotransferase (EC 2.7.8.1)), and phosphorylcholine-ceramide (ceramide cholinephosphotransferase (EC 2.7.8.3)) transferases in control and hypothyroid chick liver for a period of 40 days. The specific activity of all three transferases began to decline after the chicks were on the propylthiouracil-containing diet for 5 days and steadily declined, reaching levels 10-15% of the controls after 15 days. These low levels were maintained for as long as the chicks were on this diet. Administration of L-thyroxine (15 mug/100 g of body weight) to the hypothyroid chicks caused a marked increase in the specific activities of all three transferases, reaching levels similar to those seen in the control chicks in 36-48 h. The specific activities then declined as the chicks were maintained on the diet of propylthiouracil, reaching the former low levels after 120 h. Administration of cycloheximide alone to the hypothyroid chicks caused a rise in the specific activities of the transferases after 24 h approximately equal to that caused by thyroxine alone, while thyroxine and cycloheximide together were no different than either alone. These studies indicate that in some manner circulating thyroxine controls the activities of enzymes involved in the biosynthesis of phosphatidylcholine, phosphatidylethanolamine, and sphingomyelin in chick liver endoplasmic reticulum. There was no evidence that induction of hypothyroidism by propylthiouracil had any effect on the activities of these enzymes in the CNS.  相似文献   

12.
An attempt was made to evaluate the protective efficacy of maternal antibodies in chicks against salmonellosis. Layer chicks ageing 21 days were individually vaccinated with 100 microg of Salmonella enterica subspecies enterica serovar Weltevreden (BM 1643) toxoid adjuvanted with vitamin E subcutaneously. After 90 days of the primary vaccination the birds were given booster dose of the vaccine. The saline extract of the yolk of eggs laid by the vaccinated birds yielded agglutination and ELISA titres ranging from 43.2 +/- 5.33 to 75.2 +/- 6.26 and 4.987 x 10(3) +/- 0.54 to 5.89x103 +/- 0.56, respectively. Sera of chicks hatched from eggs laid by the vaccinated layers were also subjected to agglutination and ELISA. Agglutination and ELISA titres on the 5th day--post hatching (dph) were 21.6 +/- 1.75 and 4.025 x 10(2) +/- 0.59, while on the 10th dph titers were 13.6 +/- 1.65 and 1.21 x 10(2) +/- 0.60, respectively. It was also observed that only one out of 6 chicks died when challenged with 2 x 10(9) CFU of S. serovar Gallirarum at the age of 7 days showing 83.33% protection. Thus it can be concluded that passive immunity confided by Salmonella enterica subspecies enterica serovar Weltevreden (BM 1643) toxoid can protect chicks against salmonellosis during their early days of life.  相似文献   

13.
The probable world first captive breeding success in Chilean Brown Pelican (Pelecanus occidentalis thagus) in captivity is reported. Two chicks were hand reared at Walsrode Birdpark, Germany in 2006. Parents were imported in October 2005 and were wild birds that had been injured and subsequently rescued. All 10 adult birds demonstrated detrimental and chronically handicaps. First eggs were laid in January 2006. Eggs were incubated artificially at 37.1 °C and 56% rel. humididty. Two chicks hatched after 33 days of incubation. First feeding was made one day after hatching in the morning. Food was given 5 times a day. Until the 8th day after hatching, exclusively cut naked baby rats were fed. For stimulating the digestion and providing a good intestinal flora Lactobacillus powder was used and food was warmed up before application. After 8 days the diet was changed to fish. For development see figures. Worth to mention is the black-purple colour of the freshly hatched chicks which became successively paler with age. Also the development of the feather areas is characteristic for this (sub)-species. Taxonomy is discussed with some morphological arguments that are typical for subspecies. Nevertheless, some indications of possible breeding barriers between subspecies could support the suggestions for species status. Hatching and rearing data are compared with dates from other zoos and species of pelicans. The good development of the Walsrode birds based on the data and methods described leaves this article useful as a reference guideline for hand rearing pelicans.  相似文献   

14.
THE GUT FLORA OF THE CHICK. II. THE ESTABLISHMENT OF THE FLORA   总被引:1,自引:1,他引:0  
SUMMARY: Viable counts were made in three media of material from the crop, gizzard, duodenum, ileum and caeca of chicks. Groups of birds 2, 4, 7, 10, 13, 16 and 30 days old were studied. The results showed that a balanced gut flora is established one day after feeding. An indication of the actual development of the flora was obtained in chicks 4 hr after feeding. The relationship between the flora at different ages and that in newly-hatched chicks before feeding is discussed.  相似文献   

15.
The probable world first captive breeding success in Chilean Brown Pelican (Pelecanus occidentalis thagus) in captivity is reported. Two chicks were hand reared at Walsrode Birdpark, Germany in 2006. Parents were imported in October 2005 and were wild birds that had been injured and subsequently rescued. All 10 adult birds demonstrated detrimental and chronically handicaps. First eggs were laid in January 2006. Eggs were incubated artificially at 37.1 °C and 56% rel. humididty. Two chicks hatched after 33 days of incubation. First feeding was made one day after hatching in the morning. Food was given 5 times a day. Until the 8th day after hatching, exclusively cut naked baby rats were fed. For stimulating the digestion and providing a good intestinal flora Lactobacillus powder was used and food was warmed up before application. After 8 days the diet was changed to fish. For development see figures. Worth to mention is the black-purple colour of the freshly hatched chicks which became successively paler with age. Also the development of the feather areas is characteristic for this (sub)-species. Taxonomy is discussed with some morphological arguments that are typical for subspecies. Nevertheless, some indications of possible breeding barriers between subspecies could support the suggestions for species status. Hatching and rearing data are compared with dates from other zoos and species of pelicans. The good development of the Walsrode birds based on the data and methods described leaves this article useful as a reference guideline for hand rearing pelicans.  相似文献   

16.
17.
18.
Genetically engineered Pseudomonas sp. strain B13(FR1) was released into laboratory-scale marine ecosystem models (microcosms). Survival of the introduced population in the water column and the sediment was determined by plating on a selective medium and by quantitative competitive PCR. The activity of the released bacteria was determined by in situ hybridization of single cells with a specific rRNA-targeting oligonucleotide probe. Two microcosms were inoculated with 10(6) cells ml-1, while an uninoculated microcosm served as a control. The number of Pseudomonas sp. strain B13(FR1) cells decreased rapidly to ca. 10(2) cells ml-1 within 2 days after the release, which is indicative of grazing by protozoa. Three days after the introduction into seawater, cells were unculturable, but PCR continued to detect cells in low numbers. Immediately after the release, the ribosomal content of Pseudomonas sp. strain B13(FR1) corresponded to a generation time of 2 h. The growth rate decreased to less than 0.04 h-1 in 5 days and remained low, probably because of carbon limitation of the cells. Specific amendment of the microcosms with 10 mM 4-chlorobenzoate resulted in a rapid increase of the growth rate and an exponentially increasing number of cells detected by PCR, but not in resuscitation of the cells to a culturable state. The release of Pseudomonas sp. strain B13(FR1) into the microcosms seemed to affect only the indigenous bacterioplankton community transiently. Effects on the community were also apparent from the handling of water during filling of the microcosms and the amendment with 4-chlorobenzoate.  相似文献   

19.
Experimental egg transmission of chicken anemia agent   总被引:1,自引:0,他引:1  
When inoculated with chicken anemia agent (CAA) via the yolk sac at 6 days of age, chick embryos could develop normally into chicks. All the chicks hatched suffered from anemia and died at 10 to 15 days of age with bone marrow aplasia. Specific pathogen free laying hens were inoculated with CAA, and eggs were collected from them over a period from 1 to 28 days after inoculation. Two of 67 chicks hatched from the eggs revealed anemia at 14 days of age. CAA was recovered from 3 of 40 chicks. From the results, a possibility of egg transmission of CAA from dams to their progeny was experimentally suggested.  相似文献   

20.
Abstract This paper examines the efficacy of 10% lambdacyhalothrin-impregnated plastic tags and a deltamethrin pour-on preparation in protecting red grouse chicks from parasitism by ticks and subsequent infection with the louping-ill virus. In 1995, ten red grouse hens ( Lagopus lagopus scoticus ) in a free-living population in north-east Scotland were fitted with lambdacyhalothrin-impregnated plastic tags, glued to radio transmitters. Chicks of more than 10 days of age from a further ten untreated radio-collared hens were caught and fitted with individual tags to the plagium. Both treatments significantly reduced tick burdens in the short term. The number of larvae and nymphs on chicks up to 45 days was less under both treatments than on control chicks and tagged chicks had fewer nymphs than chicks from treated hens. Nevertheless, treatments did not reduce viral infection rates nor increase survival to 10 weeks, possibly explained by incomplete treatment of tagged broods and/or direct or indirect mortality due to tags. In 1996 chicks in ten broods from hens with radio transmitters were individually treated at 14 days of age at a rate of lmg/kg of chick with a deltamethrin pour-on preparation. This preparation significantly reduced the number of larvae and nymphs on grouse chicks 7–10 days after application below the number on untreated controls. At 20 days from application, however, only larval numbers were lower on treated chicks. Nevertheless louping-ill virus infection prevalences were significantly reduced at 35 days of age and survival of chicks to 10 weeks increased.  相似文献   

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