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1.
The effects of ad libitum ingestion of chlordiazepoxide and sodium pentobarbital on penned cowbirds and coturnix quail were compared. The agents were incorporated into feed and offered to individually marked birds. Individual response to each agent appeared to relate more to the quantity of food ingested than to the percentage by weight of agent in the food. Response of both species to chlordiazepoxide was similar at the 15% dose despite weight differences of the birds. Responses were too variable to demonstrate significant differences when sodium pentobarbital at the 10% dose was given to both species. No deaths occurred among birds given chlordiazepoxide, whereas 4 quail and 1 cowbird died from sodium pentobarbital ingestion.  相似文献   

2.
The efficacy of penicillin G potassium (Pot-Pen) administered via drinking water to manage necrotic enteritis (NE) was investigated in a Clostridium perfringens (CP) challenge study using 1600 broiler chickens assigned to one of four treatment groups: nonchallenged, nonmedicated; challenged, nonmedicated; challenged, Pot-Pen 0.2 g/L; challenged, Pot-Pen 0.4 g/L. Overall mortality due to NE was significantly reduced among Pot-Pen-treated pens; mortality due to other causes did not differ among the treatment groups. Among all birds, growth performance parameters were significantly improved among Pot-Pen-treated pens. When considering birds randomly sacrificed 4 days post-Pot-Pen initiation, mean NE lesion scores were greatest among the challenged, nonmedicated pens; only one of 80 randomly sacrificed birds treated with Pot-Pen had NE lesions. Among the nonmedicated control pens, body weight (BW) was significantly greater among birds that did not have NE-associated lesions. When sacrificed birds were stratified by NE lesion score, there were no significant differences in BW among the treatment groups. Results of this study suggest that CP-associated subclinical disease can significantly reduce broiler performance. Furthermore, the positive effects of treatment with Pot-Pen appeared to be associated with the prevention and/or treatment of NE-specific lesions.  相似文献   

3.
Wetlands are critical habitats for birds. However, wetlands are being degraded at an accelerating rate due to global human activity, and a disproportionate fraction of wetland‐dependent bird species are in decline. We evaluated the conservation value of a new Ramsar site, Guangdong Haifeng Wetlands, China, for birds, by comparing bird communities (using line transect data) in 3 different districts: Gongping, Dongguan Lian'anwei and Dahu. We recorded 139 species of birds, including 26 species that are protected at a national level. Dahu had the highest species richness and diversity, whereas Dongguan Lian'anwei had the highest abundance of birds and the lowest species diversity. Finally, Gongping had both the lowest species richness and the lowest abundance. The endemism of constituent species differed among districts, and the bird communities were complementary. There were significant seasonal differences in the species richness and the number of individuals. Spring had the highest species richness and diversity. The present study identifies the high conservation value of Haifeng Wetlands for both waterbirds and terrestrial birds. Our findings suggest that conservation efforts in Haifeng Wetlands and other wetlands should focus not only on wintering migratory birds, but also on resident birds. To accomplish effective conservation, we should consider the reserve and surrounding wetlands as a whole, incorporating ecological research, education and local economic development.  相似文献   

4.
Five components (selenium, glutathione peroxidase, copper, superoxide dismutase, and vitamin E) of the antioxidant system of turkey poults were examined to determine if they play any role in the knockdown (KD) syndrome. All flocks were provided with feed formulated to contain monensin at 54-60 g/ton. Flock data were analyzed as a case-control study with three treatment groups (KD-affected and unaffected turkey poults from a KD flock and poults from an unaffected flock [control]). Affected turkey poults had lower (P < 0.001) serum vitamin E levels compared with unaffected poults from KD flocks or poults from unaffected flocks. No significant differences were observed for the other parameters evaluated but there was a trend towards lower copper and superoxide dismutase values in affected birds. It appears that serum vitamin E concentrations in turkey poults may play a significant role in susceptibility to or protection against KD syndrome. Other components of the antioxidant system may also be involved, and complex interactions among several body systems may be critical.  相似文献   

5.
为选择草地施肥的肥料种类,减少施肥对乌蒙半细毛羊产业的影响,在威宁县凉水沟种羊场多年生人工草地开展施肥和放牧试验。 结果表明:凉水沟种羊场人工草地牧草铜含量相对较低,但仍高于乌蒙半细毛羊营养需要标准;施肥极显著增加牧草氮含量(P<0.01),各施肥处理之间没有明显差异。硫酸铵施肥显著增加牧草硫和锌含量(P<0.01),显著降低了牧草硒的含量(P<0.01)。放牧试验结束时,施硫酸铵草地的乌蒙半细毛羊血液中铜、铁和硒的含量极显著低于施硝酸铵草地和对照组(P<0.01), 动物血液锌和硫含量极显著高于硝酸铵施肥牧场和对照组(P<0.01)。硫酸铵施肥牧场的乌蒙半细毛羊血红蛋白、红细胞压积容量极显著低于硝酸铵施肥牧场和对照牧场(P<0.01),血清铜蓝蛋白含量、血清超氧化物歧化酶活力、血清谷胱甘肽过氧化物酶活力和血清过氧化氢酶等抗氧化酶的活力极显著低于硝酸铵施肥牧场和对照牧场(P<0.01),丙二醛的含量显著高于硝酸铵施肥牧场和对照牧场(P<0.01)。血液其他矿质元素和血液指标及血清生化值在2个施肥处理和对照之间均差异不显著。 因此得出结论,草地施肥的种类需要根据土壤矿物质分布和含量情况确定,铜含量低的牧场不适合硫酸铵施肥,硫酸铵施肥明显影响了乌蒙半细毛羊机体抗氧化系统功能。  相似文献   

6.
Copper sulfate was added to the diet of broiler chickens from 1 day to 3 weeks of age at the rate of 0.05% to 0.20% in order to evaluate its influence on the incidence of oral lesions. Both the incidence and severity of oral lesions showed a significant linear increase as the concentration of copper sulfate increased. Adding a level of sulfate equivalent to that produced by the highest level of copper sulfate failed to induce oral lesions. The severity of gizzard erosion also increased as the concentration of copper increased. Dietary copper sulfate supplementation should be considered a possible cause of oral lesions seen during the necropsy of avian species.  相似文献   

7.
Host range of avian influenza virus in free-living birds   总被引:17,自引:0,他引:17  
Isolation of avian influenza virus (AIV) has been reported from 12 orders and 88 species of free-living birds. Most isolations are reported from species in the orders Anseriformes and Charadriiformes and it is recognized that species in Anseriformes represent important reservoirs of AIV. Morbidity and mortality among free-living birds attributable to AIV infection are rare, but differences in prevalence of AIV occur within and between avian species. Seasonal variation has been reported from free-living and sentinel ducks with peak AIV infection occurring in late summer and early fall. Prevalence of AIV is age-related, with highest isolation rates reported from juvenile birds. Differences in susceptibility to AIV infection among species have been demonstrated under experimental conditions. The dynamics and epidemiology of species-related variation in populations of free-living birds require further study.  相似文献   

8.
Addition of copper sulphate (about 200 mg per kg) to conventional diets produced a small, though variable, growth response and improved food conversion in broilers maintained under commercial conditions. In some experiments interactions were found between sex or coccidiostat and copper in the diet. Broilers fed on diets containing greater concentrations of copper (between 400 and 600 mg per kg) exhibited reduced growth rate and food intake. The gizzard linings of birds receiving diets containing 600 mg CuSO4 per kg showed extensive damage. This damage was attributable to a massive increase in the shedding of the gizzard glandular cells into the koilin layer and to disruption and cessation of koilin production. Similar though less severe gizzard changes occurred in birds which received 400 mg per kg and there was a slight increase in cellular desquamation in some of the birds receiving 200 mg per kg. High concentrations of copper were found in the gizzard lining and caecal contents of birds receiving supplementary copper and there was a progressive increase in the concentration of copper in the litter on which such birds had been reared.  相似文献   

9.
We investigated the effect of in ovo administered reovirus vaccines on the immune responses of specific-pathogen-free chickens. T-cell mitogenic responses to concanavalin A were numerically lower at 9 and 12 days of age and significantly lower at 6 days of age in birds vaccinated with a commercial reovirus vaccine compared with unvaccinated birds or birds vaccinated with an experimental reovirus-antibody complex vaccine. There were no significant differences in proportions of subpopulations of helper (CD4+CD8-) or cytotoxic (CD4-CD8+) T cells except at 12 days of age, when the percentages of CD4-CD8+ cells in the two vaccinated groups were statistically higher than in the nonvaccinated group. B-cell populations were not different among vaccine groups except at 9 days of age, when the vaccinated groups had the highest level of B cells. This commercial reovirus vaccine should not be given in ovo to embryos having little or no maternal antibody, otherwise immunosuppression may occur in the chicks. The addition of the antibody complex to the vaccine prevented this T-cell immunosuppression.  相似文献   

10.
试验选用64羽平均体重为(3.73±0.10)kg健康爱拔益加成年肉公鸡,测定了赖氨酸硫酸盐和赖氨酸盐酸盐的赖氨酸消化率。将试验鸡随机分为4个处理,每个处理4个重复,每个重复4羽。处理1为绝食组;处理2为酪蛋白组;处理3为酪蛋白日粮添加赖氨酸硫酸盐组;处理4为酪蛋白日粮添加赖氨酸盐酸盐组。分别采用酪蛋白法和绝食法测定氨基酸的内源损失。结果表明:①利用酪蛋白法和绝食法测定的内源损失差异不显著(P>0.05);②赖氨酸硫酸盐的赖氨酸表观消化率为87.75%,利用酪蛋白法和绝食法测得的真消化率分别为99.34%和98.64%;③赖氨酸盐酸盐的赖氨酸表观消化率为87.81%,利用酪蛋白法和绝食法测得的真消化率分别为99.37%和98.67%。综上可得,采用酪蛋白法和绝食法测定的氨基酸内源损失无显著性差异;赖氨酸硫酸盐与赖氨酸盐酸盐的赖氨酸消化率差异不显著。  相似文献   

11.
The long-term effects of supplementing Leghorn-type chickens with dietary L-carnitine after hatching for 4 weeks on growth, lymphoid organ weights, humoral and cell-mediated immune responses were assessed in a 12-week study. A commercial starter feed supplemented with 0 (control), 100 (LC) or 1,000 (HC) mg L-carnitine/kg was offered to day-old ISA Brown cockerels for 4 weeks, then all birds were given a commercial pullet grower feed for another 8 weeks. No differences (p > 0.05) in growth rates, feed intake or feed utilisation efficiency existed among the dietary treatments throughout the study. Compared with control birds, HC-fed birds had a lower (p < 0.05) thymus weight relative to bodyweight (BW) at Week 4, but a higher (p < 0.05) relative thymus weight at Week 12. A higher (p < 0.05) serum primary antibody response to sheep red blood cells (SRBC) in HC-fed birds than in the other two groups was also detected at Week 12. Relative spleen or bursa weights and cutaneous responses of toe webs to phytohaemagglutimin (PHA) (an in vivo indicator of cell-mediated immune responses) did not differ (p > 0.05) among dietary treatments at any time. It is concluded that a short-term supply of dietary L-carnitine to a conventional commercial feed after hatching enhanced subsequent humoral immunity in Leghorn-type chickens. Further study is warranted to confirm such a long-term effect.  相似文献   

12.
1. The carry-over effects of supplementing Leghorn-type chickens with yeast RNA as a dietary source of nucleotides for 4 weeks on growth, lymphoid organ weights and immune responses were assessed in a 12-week study. 2. A commercial starter feed supplemented with 0 (control), 5 (LR) or 10 (HR) g yeast RNA/kg was offered to 1-d-old male ISA Brown chicks for 4 weeks, and then all birds were given a commercial pullet grower feed for another 8 weeks. Growth performance, antibody responses to sheep red blood cells (SRBC) and cutaneous reactivity of toe webs to phytohaemagglutinin (PHA)-M were measured at 4-week intervals. 3. Growth rates, feed intake and feed efficiency were not affected by dietary yeast RNA during the supplementary period, but birds previously offered the HR diet grew faster than control birds during weeks 4 to 8.4. LR-fed birds had a higher spleen weight relative to body weight (BW) than control birds at week 4, but this effect was not detected at other times. 5. Serum primary antibody levels against SRBC were not affected by dietary yeast RNA at any time. 6. The toe-web PHA response was significantly higher at week 8 in control birds than in birds previously given the LR diet, although no difference among dietary treatments was observed at other times. 7. It is concluded that the addition of yeast RNA as a source of nucleotides to a commercial diet selectively stimulated the development of the spleen in young birds, but this effect did not persist into a later stage of the bird's life.  相似文献   

13.
比较酵母铜作为新型铜源添加剂与硫酸铜在大鼠上的饲喂效果。选择血缘相近,体重在60~90g的Wistar健康雌鼠66只,按2因子完全随机设计,分为11个处理,每个处理6个重复,试验期10d。采用酪蛋白、玉米淀粉纯合缺铜饲粮作为基础饲粮,分别以酵母铜和硫酸铜2种不同的铜源添加10、30、60、100、250mg/kg5个水平。结果表明:不同铜源、不同铜水平、不同铜源与不同铜水平互作之间,大鼠的平均日增重(ADG)、平均日采食量(ADFI)差异均不显著(P>0.05);但是酵母铜与硫酸铜相比,ADG和ADFI分别提高了2.5%和3.5%。不同铜源、不同铜水平、不同铜源与不同铜水平交互作用,对大鼠血清铜蓝蛋白、铜锌超氧化物歧化酶(CuZn-SOD)、肝铜含量都存在极显著的影响(P<0.01)。由此可见,不同铜源和水平能够显著影响大鼠对铜的吸收利用,且酵母铜源较硫酸铜源的效果更优。  相似文献   

14.
During the past 2 decades, the potential for excessive exposure of pet birds to zinc has become a concern for many pet bird owners. Ideally, avian zinc toxicosis is diagnosed on the basis of history of exposure to zinc, radiographic evidence of ingested metal, occurrence of melena, detection of an elevated plasma zinc concentration, and response to treatment. However, most pet birds suspected of having zinc toxicosis present with vague signs and lack of radiographic evidence; therefore, the diagnosis relies on the presence of an elevated plasma zinc concentration. A question was, is there a significant diurnal variation in the zinc concentration in psittacine birds and could this be clinically relevant? Because studies in other species have shown that zinc is not the only element that shows a diurnal variation, the authors examined 13 other plasma elements including arsenic, cadmium, calcium, cobalt, copper, iodine, iron, magnesium, manganese, molybdenum, potassium, selenium, and total phosphorus. Fifteen adult psittacine birds housed in the same aviary were used in this study. Three blood samples, separated by 4 hours, were taken from the right jugular vein in each bird. All elements were measured in plasma. Zinc, copper, and molybdenum revealed diurnal fluctuations. The results of this study suggest that interpretation of clinical samples may be more complicated than previously believed. Furthermore, on the basis of the results of this study, it is possible that some avian reference ranges may need to be reexamined.  相似文献   

15.
About 150 rare, adult, yellow-eyed penguins died over a short period during the summer of 1989-1990 on the Otago Peninsula. These were from a total mainland population estimated at 240 breeding pairs. Penguin chicks and non-breeding birds were not affected, but there were indications of shortages in feed supply for birds that bred successfully. Thirteen dead penguins were examined. In ten birds, the cause of death was not established. Although it was commonly found that adult birds had little or no food in their gut, none were considered to have starved to death. No consistent pathological lesions were found, nor were any viruses, Chlamydia or significant bacteria recovered from selected tissues. Toxicology tests ruled out poisoning by copper, zinc, iron, lead, arsenic, selenium, cadmium, mercury, organophosphates, organochlorines, polychlorinated biphenyls, hexachlorobenzene or the toxins of Clostridium perfringens, Clostridium botulinum and dinoflagellates. The problem did not recur during the following summer.  相似文献   

16.
动物园鹦鹉科鸟类H5 N1禽流感疫苗免疫后效果监测   总被引:1,自引:0,他引:1  
多年来动物园虽然严格按照国家强制要求对园内饲养的野生鸟类进行禽流感疫苗的免疫接种工作,但是对于接种后各种鸟类免疫效果的问题仍未有研究。本次研究主要目的为探究圈养鸟类免疫商品化禽流感疫苗后的免疫效果如何,以及各个物种对疫苗的免疫应答水平是否相同。实验中选取动物园几种圈养小型鹦鹉科鸟类为实验对象,对其进行禽流感H5N1亚型疫苗免疫接种后,利用血凝(HA)及血凝抑制(HI)实验监测禽流感抗体水平变化规律,评估免疫效果。从初步的实验结果发现,鹦鹉科鸟类仅接种一次商品化禽流感疫苗,其免疫应答水平普遍偏低,免疫效果不理想。根据实验结果,尝试性地以虎皮鹦鹉为实验对象,尝试调整免疫程序后再次进行禽流感疫苗的免疫接种,通过多次尝试找出较好的免疫程序,使得虎皮鹦鹉的禽流感疫苗免疫效果得到改善,为今后制定出适合其他种类野生鸟类的禽流感免疫程序提供了科学依据。  相似文献   

17.
ABSTRACT: The relationship between stress and disease is thought to be unambiguous: chronic stress induces immunosuppression, which likely increases the risk of infection. However, this link has not been firmly established in wild animals, particularly whether stress hormones affect host responses to zoonotic pathogens, which can be transmitted to domesticated animal, wildlife and human populations. Due to the dynamic effects of stress hormones on immune functions, stress hormones may make hosts better or poorer amplifying hosts for a pathogen contingent on context and the host species evaluated. Using an important zoonotic pathogen, West Nile virus (WNV) and a competent host, the Northern Cardinal (Cardinalis cardinalis), we tested the effects of exogenous corticosterone on response to WNV infection. Corticosterone was administered at levels that individuals enduring chronic stressors (i.e., long-term inclement weather, food shortage, anthropogenic pollution) might experience in the wild. Corticosterone greatly impacted mortality: half of the corticosterone-implanted cardinals died between five - 11 days post-inoculation whereas only one of nine empty-implanted (control) birds died. No differences were found in viral titer between corticosterone- and empty-implanted birds. However, cardinals that survived infections had significantly higher average body temperatures during peak infection than individuals that died. In sum, this study indicates that elevated corticosterone could affect the survival of WNV-infected wild birds, suggesting that populations may be disproportionately at-risk to disease in stressful environments.  相似文献   

18.
During 2003, 278 adult pigeons (Columba livia) and 54 birds of 11 other free-living species were caught in the various locations in the City of Zagreb, Croatia. Sera from 182 pigeons were tested for the presence of antibodies against Chlamydophila (C.) psittaci by ELISA test and 174 of them (95.6%) were found positive. Because of the high positivity rate in sera, cloacal swabs of 278 pigeons as well as 54 other species of free-living birds were tested for the presence of C. psittaci antigen. Fourty-four of the 278 pigeons (15.83%) were antigen positive, whereas all 54 of the wild birds were negative. Antigen-positive pigeons were euthanised and examined pathomorphologically and cytologically. Findings of specific antibodies and antigen of C. psittaci confirmed the high rate of infection among urban pigeons in the City of Zagreb, fortunately not among other free-living birds. Although the pigeon serovars of C. psittaci are considered to be of moderate pathogenicity for humans, the identification of 15.8% antigen-positive birds represents a potential source of infection to humans, especially for elderly people and immunodeficient patients, as well as for poultry in the Zagreb city area.  相似文献   

19.
Abstract

Ichthyophthirius multifiliis is a protozoan that may infest and significantly damage cultured fish species. The purpose of this study was to measure the efficacy of copper sulfate in treating ichthyophthiriasis. Fingerling channel catfish Ictalurus punctatus exposed to at least 2,000 theronts of I. multifiliis per liter of water developed consistent infestations of I. multifiliis (20 or more trophonts on the dorsal surface of the head of the fish). Infestation was observed in untreated controls at day 5 after exposure and mortality occurred after day 10. Coexposure studies with theronts and different concentrations of copper sulfate revealed that all theronts were killed at concentrations greater than 0.05 mg/L. To determine the effect of copper sulfate in the treatment of ichthyophthiriasis, fish were exposed to the parasite until trophonts were observed (day 5), and they were subsequently treated with copper sulfate. The lowest effective concentration of copper sulfate for treatment of ichthyophthiriasis (i.e., after infestation was observed in the fish) was 0.4 mg/L. To assess the effects of various water quality conditions on copper treatment, total suspended solids (TSS) and pH were varied during treatment of ichthyophthiriasis. Concentration of TSS was inversely correlated to the efficacy of copper sulfate for I. multifiliis infestations, whereas no relationship was observed between pH and efficacy of a single copper sulfate dose. The results indicated that copper sulfate can be used to treat ichthyophthiriasis at concentrations of 0.4 mg/L for at least 5 d under the specific water conditions used in this study (pH, 7.45 ± 0.27; temperature, 20.5 ± 0.7°C; alkalinity, 176.6 ± 28.1 mg/L as CaCO3) and that efficacy of copper sulfate was affected more by TSS concentration than by pH.  相似文献   

20.
Wild birds are considered a potential reservoir or a carrier of viral diseases and may therefore play a role in the epidemiology of economically important or zoonotic diseases. In 2001 and 2002, a survey with special emphasis on virus isolation in migrating waders and some other birds were conducted. In one of the most important inland resting sites for migratory waterfowl, tracheal and cloacal swabs were collected from 465 waders representing 19 different species, and 165 other birds that were not captured on purpose. A total of 42 avian viruses were isolated, 34 of these were identified as paramyxoviruses (PMVs). The majority of isolates came from waders and wild ducks, and were characterized as PMV-1. In contrast, PMV-4 was found in wild ducks only, PMV-6 was mainly detected in wader species. Four avian influenza viruses (AIVs), belonging to H4 and H3 haemagglutinin subtype, were isolated from wild duck species. Furthermore, four reo-like viruses were isolated from one particular wader species for the first time. The majority of virus positive birds were <1 year old and did not show any clinical symptoms. There was no evidence for the presence of West Nile virus in these birds. These results confirm that the restricted resting sites in Western Europe must be considered as important locations for the intra- and interspecies transmission of avian viruses.  相似文献   

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