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1.
1. The influence of zinc bacitracin, an antibiotic growth promoter, and the combined influence of two environmental factors (8 h of darkness and access to sand) on health and welfare variables were studied in 96 broiler chickens (kept as pairs). 2. Chickens fed with zinc bacitracin (ZB) had a higher frequency of tibial dyschondroplasia (TD) and a higher frequency of dustbathing than chickens fed without zinc bacitracin. 3. When 42 d old, chickens exposed to 8 h of darkness and access to sand were heavier than chickens reared under continuous light and with no access to sand. 4. Fluctuating asymmetry was higher in the 'light/no sand' groups than in the 'night/sand + ZB' group. 5. There was a negative correlation between tonic immobility and weight and a positive correlation between weight and TD.  相似文献   

2.
C Riddell 《Avian diseases》1975,19(3):497-505
Surgical severance of the gastrocnemius and flexor tendons on the posterior aspect of the tibiotarsal-tarsometatarsal joint in one leg resulted in unilateral lameness in chickens that were susceptible to tibial dyschondroplasia. Perotic-like deformation developed in the operated leg, while the tibiotarsus in the unoperated leg was thicker and bowed in an anterior direction. In nine of 43 chickens with tibial dyschondroplasia the severity of the lesion differed markedly between the operated and unoperated legs. The more severe lesion was in the operated leg in 6 birds, and in the unoperated leg in 3 birds. No evidence was found to support the hypothesis that weight-bearing may be important in the pathogenesis of tibial dyschondroplasia.  相似文献   

3.
Female broiler chicks were randomly placed into two groups; one was treated twice daily with TDP-1 (a mycotoxin produced by Fusarium roseum), the other was controls. Chicks were sacrificed after 2, 4, 6, 8, 10, and 14 days of treatment and were evaluated for tibial dyschondroplasia. TDP-1-treated chicks examined after 2, 4, or 6 days of treatment had either no gross lesions (2 days) or mild gross lesions (4 and 6 days); growth plates from these groups did not have ultrastructural changes. TDP-1-treated chicks examined after 8, 10, or 12 days of treatment had moderate to severe gross lesions of tibial dyschondroplasia. These groups also had intracellular lipid accumulation and necrosis of chondrocytes within the retained cartilage. It was concluded that the cellular changes in tibial dyschondroplasia develop only after the cartilage accumulates; the changes are sequelae, possibly due to nutrient depletion from an increased distance between chondrocytes and perforating epiphyseal vessels, their nutrient source.  相似文献   

4.
The objective of this study was to evaluate the effects of two methods of early-age water restriction on performance, some immune responses, serum metabolites, and prevalence of leg weakness in broiler chicks. One-hundred-eighty-seven-day-old chicks (Ross 308) were allocated to three treatments with four replicates based on a completely randomized design. Treatments included the control group, where birds had free access to water, and water-restricted groups, where access to water was limited to three 2-h periods (WRT1) or a 12-h period (WRT2) per day from days 7 to 17. Chicks in the control group were significantly heavier (P < 0.05) at 17 and 46 days of age compared to the restricted birds. In the WRT2 group, feed intake decreased significantly over the 17- to 28-day period while feed conversion ratio was poorer during water restriction (P < 0.05). Antibody titers against Newcastle and SRBC were higher (P < 0.05) for chicks with ad libitum access to water. Birds in the restricted groups exhibited a higher heterophil to lymphocyte ratio compared to the control group (P < 0.05). The treatments had no significant impact on serum metabolites including protein, triglyceride, total cholesterol, high-density lipoprotein and low-density lipoprotein cholesterols, calcium, and phosphorus concentrations. Walking ability, tibial dyschondroplasia, foot pad, hock burn, and valgus/varus angulation were not significantly influenced by water restriction. In conclusion, the current results indicate that early-age water restriction negatively influenced productive traits and immunological responses of broiler chicks and failed to have any favorable impacts on leg health.  相似文献   

5.
1. The effect of divergent selection for high (H) or low (L) incidence of tibial dyschondroplasia (TD) for 7 generations on blood calcium (Ca) and phosphorus (P) concentrations was studied. 2. The chicks used in this experiment were obtained from diallel crosses between H and L lines to obtain HH, HL, LH, and LL lines. A random-bred control (CC) line was also used. 3. The chicks were reared under standard management conditions. Body weight and plasma Ca and P concentrations were measured at 2, 4, and 7 weeks of age. Incidence of TD was recorded at 4 and 7 weeks. 4. Although HH birds had lower body weights than the other lines, there was no significant effect attributable to line selection for body weight at 2, 4, and 7 weeks of age. 5. The LL line birds had no incidence of TD at 4 weeks of age; however, the incidence of TD in LL line birds was 5.3% at 7 weeks of age. The incidence of TD was higher in HH line birds than the other line at 4 and 7 weeks of age. 6. Plasma Ca and P concentrations and Ca:P ratios increased with age. These results showed that HH line birds had higher plasma Ca, lower plasma P and higher Ca:P ratios than birds of the LL line.  相似文献   

6.
1. The aims of this study were to determine (1) the effect of light-dark schedules on the walking ability, the risk of tibial dyschondroplasia (TD) as well as the duration of tonic immobility (TI) reactions in commercial broiler flocks and (2) the effect of a daily dark period and reduced density on the behaviour of broiler chickens. 2. Experiment 1. Group 1 had a 2 to 8 h daily dark period from 2 to 26 d of age (light-dark programme A) at a stocking density of 28.4 chicks/m2. Group 2 had 8 h of darkness daily from 2 to 38 d of age (light-dark programme B) at 24 chicks/m2. The control group had 24 h continuous light at 28.4 chicks/m2. 3. Experiment 2. Behaviour was studied with and without a daily 8 h dark period and at high (30 chicks/m2) and low (18 chicks/m2) stocking densities. 4. Programme B reduced the prevalence of impaired walking ability, corresponding to gait score > 2, when compared with controls. The effect on walking ability corresponding to gait score > 0 approached significance. 5. Both light-dark programmes reduced the occurrence of TD. Programme B (combined with reduced stocking density), however, had the greater effect. 6. Both light-dark programmes reduced the duration of TI, compared with controls (mean = 426 s) Programme B resulted in a larger reduction (alpha = -156.9 s) than programme A (alpha = -117.0). 7. The proportions of chicks drinking, eating, pecking, scratching, standing and performing vertical wing-shakes increased--both when the 8 h dark period and the reduced stocking density were applied separately and in combination (experiment 2). 8. For all behaviours, except standing, the effect of the dark period was largest in broilers kept at the high stocking density (d 40).  相似文献   

7.
C Riddell 《Avian diseases》1975,19(3):443-462
Two strains of broiler chickens selected for a high and a low incidence of tibial dyschondroplasia were fed a standard broiler starter ration with and without added chloride. Development of tibial dyschondroplasia was studied by radiography and serial necropsies. Lesions of tibial dyschondroplasia were mild in the low-incidence strain, regardless of ratio. The defect was more severe in the high-incidence strain and most severe in those birds fed the high-chloride ration. An abnormal thickening of the growth plate was apparent in the high-incidence strain as early as 2 weeks of age and became progressively more severe with age. No significant differences were noted in serum calcium, phosphorus, alkaline phosphatase, pCO2, or bone ash between strains of birds or between birds of the same strain fed different rations. Birds fed the high-chloride ration had a higher serum chloride and a lower serum bicarbonate and blood pH than birds on the standard ration.  相似文献   

8.
本试验旨在研究福美双和铜对肉鸡胫骨软骨发育不良、血清相关酶活性和组织铜含量的影响。100羽1日龄AA肉鸡随机分为4组,从8日龄起分别给予基础日粮(对照组),福美双日粮(基础日粮+福美双100 mg/kg),福美双低铜日粮(基础日粮+福美双100 mg/kg+CuSO4.5H2O 50 mg/kg),福美双高铜日粮(基础日粮+福美双100 mg/kg+CuSO4.5H2O 100 mg/kg),试验期至21日龄。结果表明:(1)日粮中添加福美双(100 mg/kg)能显著增加肉鸡TD的发生率;添加铜能降低福美双的这种作用,两者之间存在明显的互作关系;(2)与对照组相比,福美双组和福美双高铜日粮组肉鸡血清钙、磷水平明显升高(P<0.05);血清ALT水平在各组之间无显著差异;血清ALP、AST水平,福美双高铜日粮组与其余各组相比明显升高,差异显著(P<0.05);(3)与对照组相比,其余各组肉鸡胫骨长度均显著下降(P<0.05);(4)日粮中铜添加可提高各组织中铜的沉积;添加福美双能提高肝脏、肾脏、胰腺中铜的沉积,同时降低铜在肾脏中的沉积,而铜的添加能够降低福美双所引起的肾脏铜的增加。提示福美双可能通过损伤肝、肾功能,影响机体组织对铜的生物利用从而诱导肉鸡胫骨软骨发育不良的发生。  相似文献   

9.
A study was conducted to evaluate four different cholecalciferol levels (NRC; modified), using diets supplemented with 200 (control), 1500, 2500 or 3500 IU/kg of cholecalciferol (VIT‐D3). Each treatment was assigned to 3 pens of 17 broiler chicks of a commercial strain grown in an open‐sided house with sidewall curtains. At 21and 42 days, BW and feed conversion (FCR) were determined. At 42 days, five birds per pen were slaughtered to evaluate tibia and toe ash of the right leg, and incidence and severity of tibial dyschondroplasia (TD) of the left tibia and also measured dressing percentage and breast meat yield. Serum calcium and phosphorus concentrations were also determined. Haemagglutination inhibition antibody titre against Newcastle disease virus and lymphoid organs weight/body weight ratio were also determined. At both 21 and 42 days, the BW of birds fed 1500 IU/kg to 3500 IU/kg of VIT‐D3 was significantly greater than birds fed 200 IU/kg. Similarly, better FCR was observed in birds those fed diets of high level of VIT‐D3. No significant difference was observed for mortality at any age. Better dressing percentage and breast meat yield were noted in birds fed diets containing 2500 or 3500 IU/kg VIT‐D3. Both tibia and toe ash contents were increased (p < 0.05) progressively with increased concentrations of cholecalciferol in feed. The incidence of TD (percentage of birds having TD scores greater than zero) was significantly (p < 0.05) influenced by level of 3500 IU VIT‐D3/kg at 42 days. The severity of TD in birds fed diets containing 200 IU/kg VIT‐D3 was apparently higher than birds fed diets with higher levels of VIT‐D3. Concentrations of calcium and phosphorus minerals in the serum increased progressively with the high level of VIT‐D3 supplementation to birds at both 21 and 42 days of age. Feeding levels of 1500 or 3500 IU of vitamin D3 did positively affect the immune system within the parameters measured. It may be concluded that performance, bone mineralization, blood chemistry and immunity against disease in broilers could be maintained when supplementing high level of VIT‐D3 incorporated in broiler diets.  相似文献   

10.
Dustbathing behaviour of uropygial gland extirpated and intact White Leghorn hens was studied after 27 and 75 h of deprivation of dust. Thereafter the hens were given access to dust (litter) and latency and duration of their first dustbathing bout were recorded. A short latency and/or a long duration were taken to indicate a strong urge to perform dustbathing. Judged by either of these criteria the gland extirpated birds showed a higher dustbathing tendency than the intact birds and in both groups the dustbathing tendency increased from 27 to 75 h of deprivation. Because of these findings the present study failed to support the “lipid regulation theory”: that the amount of lipid in the plumage should regulate the dustbathing tendency. Rank in the social hierarchy significantly influenced latency and duration of dustbathing but there was no simple correlation. After two weeks with constant access to litter no differences in the amount of feather lipids could be found between gland-extirpated and intact birds.  相似文献   

11.
Two experiments were conducted to study the effects of age of the maternal flock (27 vs. 57 weeks of age at time the eggs were set) and strain of broiler chicks (Cobb 500, Ross, Arbor Acres, and Avian) on the incidence of tibial dyschondroplasia (TD) in broiler cockerels grown to 3 weeks of age. The chicks were fed a corn/soybean meal-based diet containing 3145 kcal metabolizable energy corrected for nitrogen retention (MEn)/kg, 24% protein, and 0.50% available phosphorus. Each treatment was replicated four times with eight chicks per pen. In Expt. 1, chicks from the old parent flock had significantly higher body weights (P < or = 0.05) than those from the young parent flock. There were no significant differences in feed efficiency or incidence of TD. In Expt. 2, body weights, feed efficiency, and TD were unaffected by strain.  相似文献   

12.
Two trials were conducted to determine if thiram-induced tibial dyschondroplasia (TD) in chickens was linked to a vitamin D deficiency and calcium homeostasis dysregulation, and whether feeding vitamin D fortified diets may prevent it. Day-old chickens were given grower diets containing different vitamin D products throughout the experiment until necropsy on day 16. Half of the birds in each feed group received thiram at levels of 100 ppm (trial 1) or 50 ppm (trial 2) between days 7-9 to induce TD. The birds were weighed, bled, and euthanized to determine TD incidences and severity by examining the growth plates. Tibial bones were used to measure biomechanical strength and ash content. Blood concentrations of 25-hydroxyvitamin D, Ca, P, alkaline phosphatase, and creatine kinase were measured in serum that showed no differences between different groups. Thiram reduced body weight and induced TD regardless of any vitamin D treatment to the same extent as untreated birds.  相似文献   

13.
Exacerbative effect of vitamin A on malabsorption syndrome in chicks   总被引:1,自引:0,他引:1  
The interaction between malabsorption syndrome (MAS) and dietary vitamins A and D was studied in broiler chicks reared in floor pens for 4 weeks. The chicks were naturally infected with MAS, whereas hatchmates fed the same diets but in a separate facility (battery brooder) did not exhibit signs of MAS and, therefore, were considered controls. MAS significantly reduced body weights, bone ash, serum calcium and phosphorus concentrations, and liver lipids and increased the incidence of skeletal abnormalities (tibial dyschondroplasia and rickets). Rather than ameliorating the effects of MAS, vitamin A caused a further reduction in body weight and bone ash. A possible nutrient interaction between vitamin A and vitamin D or vitamin E in birds with MAS may account for the exacerbative effect of vitamin A.  相似文献   

14.
Antibiotics are used in the livestock industry not only to treat disease but also to promote growth and increase feed efficiency in less than ideal sanitary conditions. However, certain antibiotic families utilized in the poultry industry have recently been found to adversely affect bone formation and cartilage metabolism in dogs, rats, and humans. Therefore, the first objective of this study was to determine if certain antibiotics used in the poultry industry would inhibit in vitro cartilage degradation. The second objective was to determine if the antibiotics found to inhibit in vitro cartilage degradation also induced tibial dyschondroplasia in growing broilers. Ten antibiotics were studied by an avian explant culture system that is designed to completely degrade tibiae over 16 days. Lincomycin, tylosin tartrate, gentamicin, erythromycin, and neomycin sulfate did not inhibit degradation at any concentration tested. Doxycycline (200 microg/ml), oxytetracycline (200 microg/ml), enrofloxacin (200 and 400 microg/ml), ceftiofur (400 microg/ml), and salinomycin (10 microg/ml) prevented complete cartilage degradation for up to 30 days in culture. Thus, some of the antibiotics did inhibit cartilage degradation in developing bone. Day-old chicks were then administered the five antibiotics at 25%, 100%, or 400% above their recommended dose levels and raised until 21 days of age. Thiram, a fungicide known to induce experimental tibial dyschondroplasia (TD), was given at 20 ppm. Birds were then killed by cervical dislocation, and each proximal tibiotarsus was visually examined for TD lesions. The results showed that none of these antibiotics significantly induced TD in growing boilers at any concentration tested, whereas birds given 20 ppm thiram had a 92% incidence rate.  相似文献   

15.
A trial was conducted to determine the effects of dietary level of selenium on the pathogenesis of Fusarium-induced tibial dyschondroplasia (FITD) in broiler chicks, and to assess the applicability of FITD as an animal model of Kashin-Beck disease of humans. Day-old female broilers were fed diets that were deficient in selenium (0.02 ppm Se), adequate in selenium (0.15 ppm Se), or generous in selenium (0.50 ppm Se). TDP-1, the toxic component of the fungus, was administered to 15 of 26 chicks in each dietary group starting at 1 week of age and continuing until the chicks were killed at 24-30 days of age. Plasma selenium levels and hepatic glutathione peroxidase activity were significantly lower in the selenium-deficient group than in other dietary groups; these parameters were not affected by treatment with TDP-1. The mortality rate of the TDP-1-treated selenium-generous group was significantly less than that in the other TDP-1-treated groups, but there were no differences in the incidence, severity, or character of the FITD lesions among the groups. Thus, the interaction of selenium and TDP-1 did not include an effect on FITD.  相似文献   

16.
将120只1日龄AA肉鸡随机分为对照组、低浓度福美双组(50mg/kg福美双)、高浓度福美双组(100mg/kg福美双),试验进行28d。结果显示,饲料中添加福美双显著升高了血清AST、ALT和ALP水平(P〈0.05),提高了肉鸡胫骨软骨发育不良(TD)的发病率(P〈O.05),降低了肉鸡生产性能。表明福美双能通过损害肉鸡肝脏功能,影响骨代谢相关酶活性,而致发肉鸡TD。  相似文献   

17.
A sudden outbreak of lameness related to transport stress is described in a flock of male breeding turkeys. Most of the affected turkeys exhibited obvious unilateral leg disorders. All were affected with tibial or metatarsal dyschondroplasia with at least one lesion associated with a large focus of necrosis. By histological examinations, bone lesions showed the typical feature of osteomyelitis. The inflammatory bone lesions appeared at only single isolated sites and were always associated with obvious sequestra of dyschondroplastic retained cartilage. Osteomyelitis seems to be an unexpected acute complication of previous dyschondroplasia in relation with different breeding stress situations. The resulting pain of the associated lesions could be the main cause of clinical expression of lameness. The pathogenesis of the phenomenon remains uncertain.  相似文献   

18.
Oligodeoxynucleotides (ODN) containing cytosine-phosphodiester-guanine (CpG) motifs have been shown to be effective immunoprotective agents in murine models for a variety of viral, intracellular bacterial, and protozoan infections. We recently have shown that CpG ODN protects against extracellular bacterial infections in mature chickens. The objective of this study was to investigate the effect of CpG ODN on Escherichia coli septicemia in neonatal broiler chicks. Two-day-old chicks, or embryonated eggs that had been incubated for 18 or 19 days, received 50 microg CpG ODN. Three days after exposure to CpG ODN, a virulent isolate of E. coli was inoculated subcutaneously in the neck of each bird. Birds were examined for 7 days post-E. coli challenge and dinical, pathologic, and bacteriologic assessments were conducted. The control group of birds that received no CpG ODN had a survival rate of 0% to 20%. In contrast, groups that received CpG ODN, either by intramuscular or in ovo routes, had significantly higher survival rates (P < 0.0001). Bacterial counts in air sacs were significantly lower when birds or embryos were treated with CpG ODN as compared with controls. A dose as low as 10 microg of CpG ODN, administered intramuscularly, was able to protect birds significantly against E. coli challenge. Formulation of CpG ODN with 30% Emulsigen did not enhance the protection. This study demonstrates that CpG ODN has systemic protective effects in broiler chicks against E. coli infections. This is the first time that CpG ODN has been demonstrated to have an immunoprotective effect against a bacterial infection in chicks following in ovo delivery.  相似文献   

19.
Rath NC  Huff WE  Huff GR  Kannan L 《Avian diseases》2007,51(2):590-593
Tibial dyschondroplasia (TD) is a major poultry leg problem, the natural etiology of which is unknown. Certain dithiocarbamate pesticides such as tetramethyl thiuram disulfide (thiram) have been shown to induce the disease in chickens. Because many different carbamate and thiocarbamate chemicals are used in a number of agricultural, industrial, and household applications, the objective of this study was to determine whether all chemicals of these categories induce TD and whether there is a concentration-dependent relationship between the ingestion of these chemicals and the incidences and the severity of the disease. Week-old broiler chicks were fed diets containing thiram or other assorted carbamate and thiocarbamate pesticides mixed in feed for 24-48 hr between ages 8 and 10 days. The birds were killed on day 15 and the proximal tibial and tarsometatarsal growth plates were evaluated for the presence and severity of TD lesions. TD was distinguished by broadening of growth plates; upon histologic exam chondrocytes appeared to be shrunken and dead. When compared by including equimolar concentrations of these chemicals in the feed, the dithiocarbamates with more than two sulfide groups, such as disulfiram, ferbam, thiram, and ziram were potent inducers of TD, whereas those with two sulfides to no sulfide group appeared ineffective at inducing TD. Both thiram and ferbam also reduced the bird's body weights. Thiram increased the incidence and the severity of the disease, denoted by TD index, in a dose-dependent manner. These results suggest that inadvertent contamination of feed or litter with some of these or similar chemicals may cause leg problems in poultry.  相似文献   

20.
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