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1.
The objective of this review was to summarise and evaluate the current state of knowledge about chronic progressive lymphoedema in draught horses. Clinical signs of this multifactorial disorder are mainly restricted to the lower limbs, comprising progressively deteriorating skin, swelling and deformation. Although typical lesions were first reported at the beginning of the 20th century, chronic progressive lymphoedema was recognised as a specific syndrome only in 2003, and since then research has driven forward. Despite the high prevalence in some breeds and the serious economic impact, the pathogenesis is not fully understood, and the available treatment options remain symptomatic and noncurative. There is a need to improve diagnostic techniques and to develop selection tools.  相似文献   
2.
Genetic parameters for chronic progressive lymphedema (CPL)‐associated traits in Belgian Draught Horses were estimated, using a multitrait animal model. Clinical scores of CPL in the four limbs/horse (CPLclin), skinfold thickness and hair samples (hair diameter) were studied. Due to CPLclin uncertainty in younger horses (progressive CPL character), a restricted data set (D_3+) was formed, excluding records from horses under 3 years from the complete data set (D_full). Age, gender, coat colour and limb hair pigmentation were included as fixed, permanent environment and date of recording as random effects. Higher CPLclin certainty (D_3+) increased heritability coefficients of, and genetic correlations between traits, with CPLclin heritabilities (SE) for the respective data sets: 0.11 (0.06) and 0.26 (0.05). A large proportion of the CPLclin variance was attributed to the permanent environmental effect in D_full, but less in D_3+. Date of recording explained a proportion of variance from 0.09 ± 0.03 to 0.61 ± 0.08. Additive genetic correlations between CPLclin and both skinfold thickness and hair diameter showed the latter two traits cannot be used as a direct diagnostic aid for CPL. Due to the relatively low heritability of CPLclin, selection should focus on estimated breeding values (from repeated clinical examinations) to reduce CPL occurrence in the Belgian Draught Horse.  相似文献   
3.
The production and application of a freeze-dried Salmonella gallinarum vaccine are described in this report. The vaccine is stable when kept at 4 degrees C and a single injection elicits a good immunity for 2 months, though its effect gradually diminishes. Immunity is neither enhanced nor depressed by repeated injections of the live vaccine, and no interference effect was observed in experimentally infected chickens. Furazolidone therapy jeopardizes the immunogenicity of a live vaccine, but its effect can be countered by the administration of either an inactivated or a live vaccine when medication is commenced and this is followed by the application of live vaccine 6 days after cessation of medication.  相似文献   
4.
An immunofluorescent (IF) test for the serodiagnosis of Toxocara canis infections in puppies is described. Frozen sections of male adult T. canis worms were used as antigen.A group of seven puppies, 6 weeks of age, was infected orally with 10 000 embryonated T. canis eggs each. In the sera of all animals IF antibodies could be detected from approximately 4 weeks after infection onwards. Titers were detectable until the end of the observation period (22 weeks).Two puppies of the same age were infected with 30 000 or 50 000 embryonated T. canis eggs respectively. Positive IF results were also obtained in the sera of these pups from week 4 post infection (p.i.) onwards. No correlation between titer and initial number of egges administered was observed. Furthermore, no correlation was noticed between titer and number of adult worms recovered from the dogs. For comparison all sera were tested with the complement fixation (CF) test, using cuticle material of adult worms as antigen. Complement fixing antibodies could be detected in none of the serum samples.  相似文献   
5.
Immunoglobulins were analysed in the sera of pigs inoculated once with different numbers of Trichenella spiralis. Analyses for IgE were performed by homologous passive cutaneous anaphylactic (PCA) reactions and for IgG (H + L) by enzyme linked immunosorbent assay (ELISA).In the higher inoculation dose range (5,000–10,000 larvae) IgE production paralleled that of IgG (H + L). In the lower range (150,500 and 1,500 larvae) IgE production preceded IgG production in most animals.The possible significance of this finding for the early diagnosis of T. spiralis infections is discussed.  相似文献   
6.
7.
Genetic parameters for the height at withers, 27 linear type and six linear gait traits were estimated for the Belgian warmblood horse. Observations on 987 mares, mostly 3 years old, were analysed using a multi-trait animal model. The statistical model included appraiser, age and location (date × place of appraisal) as fixed effects. Genetic parameters were estimated using a canonical transformation and an expectation-maximization restricted maximum likelihood algorithm with an additional deceleration step. Estimates of heritability for the 33 linear traits were between 0.15 and 0.55. Heritability of the height at withers was 0.34 ± 0.06. Estimated genetic correlations ranged from −0.60 to 0.98 with an average SE of 0.10. The highest positive correlations were found among traits of walk and among traits of trot. Volume and the quality of legs were the most negatively correlated. Estimated genetic parameters indicated that the linear scoring system is a valuable tool to assess conformation. The full (co)variance matrix is now available for breeding value estimation to support selection for conformation and gaits.  相似文献   
8.
M. Ntawubizi  K. Raes  N. Buys  S. De Smet   《Livestock Science》2009,122(2-3):264-270
In this study, the effect of sire, sex and intramuscular fat content on the intramuscular fatty acid profile, in particular the long chain polyunsaturated fatty acids (PUFA) was investigated. Therefore, pork samples of the Longissimus thoracis were taken from 121 females and castrates that were the progeny of 5 boars. All animals had been fattened on the same diet and were slaughtered at a live weight of approximately 110 kg. Indices for the activities of Δ9, Δ6 and Δ5 desaturase, as well as elongase activity were estimated from ratios of product to precursor fatty acids. Intramuscular fat content was positively related to the total saturated fatty acid proportion (r = 0.376; p < 0.01) and the total monounsaturated fatty acid proportion (r = 0.579; p < 0.01), and inversely correlated with the total PUFA proportion (r = − 0.637; p < 0.01). A significantly higher index for Δ5 and Δ6 desaturase and elongase activity for PUFA metabolism was observed in females compared to castrate males. Sire had a significant effect on the intramuscular fatty acid profile, notably on the total n − 3 PUFA, and on most individual long chain n − 6 and n − 3 PUFA. The cis-9 C18:1/C18:0 index for Δ9 desaturase activity and the cis-11 C18:1/cis-9 C16:1 elongase activity index, as well as the combined desaturase and elongase enzyme activities in both the n − 6 and n − 3 PUFA chains were significantly influenced by sire.  相似文献   
9.
1. Male broilers of two different genetic stocks, a pure broiler sire line (A) and commercially available Ross broilers (B), were used to study the effect of haematological characteristics in juvenile chickens on the development of clinical ascitic signs. Production performance (body weight gain (BWG), feed intake (FI), feed conversion ratio (FCR)) from 448 birds per stock was measured from 2 to 5 weeks of age. Mortality was recorded from 2 to 6 weeks of age. The birds were housed at a low ambient temperature to stimulate the incidence of ascites. 2. From each stock, 32 birds with the highest (high risk: HRc) and 32 birds with the lowest (low risk: LRc) carbon dioxide tensions (pCO2) in venous blood were selected at 11 d of age. These birds were marked for future blood sampling to determine changes in pCO2 with age to relate these values to ascites susceptibility. 3. At 2 weeks of age all birds (including HRc and LRc birds) were allotted to 32 floor pens (one HRc and one LRc in each pen) per stock. Venous blood samples were collected weekly from HRc and LRc birds for blood gas analysis and haematocrit, and at week 5 also for thyroid hormone (T3, T4) concentrations in plasma. At 5 weeks of age all HRc and LRc birds were examined post-mortem, relative heart, lung, and liver weights and arterial pressure index (API) values were recorded. 4. Birds from stock A showed a lower BWG and FCR and notably higher ascites mortality compared with stock B. An effect of pCO2 tensions at d 11 was found on the incidence of ascitic signs in selected birds of both stocks up to week 5. From the HRc groups 30% of the birds showed ascitic signs, whereas this was only 8% in the LRc group. LRc birds of stock B in particular showed constant low API values (20 +/- 3%) and none of these birds showed signs of ascites. 5. Our results suggest that the ascites problem in Ross birds can be eliminated by selection for low pCO2 tensions in venous blood. Stock effects on API, liver weight, lung weight, and plasma thyroid hormone independent of pCO2 showed a more complex picture of the ascitic signs in stock A compared with B. 6. We concluded that in this experiment a high pCO2 tension in venous blood measured at d 11 was a reliable predictor for ascites susceptibility observed at 5 weeks of age. A low pCO2 tension provides an appropriate criterion for genetic selection, whereas a high pCO2 tension emphasises the necessity for intensive management in poultry houses.  相似文献   
10.
1. This experiment was carried out to evaluate the productive and physiological consequences of a slight but long term food restriction of male broiler chickens from 2 commercial strains. 2. Cobb-500 and Ross chickens were submitted to a 20% food restriction from 8 to 21 d of age. Strain, food programme and their interactive effects were analysed in terms of consequences upon performance, mortality, incidence of sudden death syndrome (SDS) and ascites syndrome (AS), index of right cardiac hypertrophy and plasma concentrations of hormones related to metabolism and growth (T3, T4, T3:T4 ratio, IGF-I and GH). 3. Although some catch-up growth was observed by refeeding previously restricted birds after 22 d of rearing, food restriction decreased (P ≤ 0.05) body weight at market age (42 d) irrespective of the strain, but improved (P ≤ 0.05) food conversion. 4. The incidence of mortality was not high in non-restricted birds but SDS and AS caused more than 50% of deaths. Hypertrophic cardiac index was observed in chickens of both strains after 4 weeks of age and was higher in ad libitum fed birds. 5. During the period of food restriction, plasma T3 and IGF-I concentrations decreased whereas plasma T4 and GH concentrations increased compared to those of the age-matched ad libitum fed counterparts. During the subsequent ad libitum feeding period, few differences in circulating hormone concentrations were observed, except for the higher mean GH litres in previously food-restricted chickens at 35 d of age. 6. These results indicate that even a non-severe food restriction negatively affects body weight of 42-d-old male broilers but these are benefits with improved food efficiency and diminished mortality from metabolic disturbances. The hormone results suggest that the degree of food restriction applied was not severe because there was a very fast adaptive response with small and transient alterations in T3, T4 and GH plasma concentrations during the period of compensatory growth.  相似文献   
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