Genetic diversity and relatedness of Fasciola spp. isolates from different hosts and geographic regions revealed by analysis of mitochondrial DNA sequences

The present study examined sequence variability in a portion of the mitochondrial cytochrome c oxidase subunit 1 (pcox1) and NADH dehydrogenase subunits 4 and 5 (pnad4 and pnad5) among 39 isolates of Fasciola spp., from different hosts from China, Niger, France, the United States of America, and Spain; and their phylogenetic relationships were re-constructed. Intra-species sequence variations were 0.0-1.1% for pcox1, 0.0-2.7% for pnad4, and 0.0-3.3% for pnad5 for Fasciola hepatica; 0.0-1.8% for pcox1, 0.0-2.5% for pnad4, and 0.0-4.2% for pnad5 for Fasciola gigantica, and 0.0-0.9% for pcox1, 0.0-0.2% for pnad4, and 0.0-1.1% for pnad5 for the intermediate Fasciola form. Whereas, nucleotide differences were 2.1-2.7% for pcox1, 3.1-3.3% for pnad4, and 4.2-4.8% for pnad5 between F. hepatica and F. gigantica; were 1.3-1.5% for pcox1, 2.1-2.9% for pnad4, 3.1-3.4% for pnad5 between F. hepatica and the intermediate form; and were 0.9-1.1% for pcox1, 1.4-1.8% for pnad4, 2.2-2.4% for pnad5 between F. gigantica and the intermediate form. Phylogenetic analysis based on the combined sequences of pcox1, pnad4 and pnad5 revealed distinct groupings of isolates of F. hepatica, F. gigantica, or the intermediate Fasciola form irrespective of their origin, demonstrating the usefulness of the mtDNA sequences for the delineation of Fasciola species, and reinforcing the genetic evidence for the existence of the intermediate Fasciola form.     

Accessing genotype by environment interaction using within- and across-country test-day random regression sire models

First-lactation test-day (TD) milk records of Luxembourg and Tunisian Holsteins were analysed for evidence of genotype by environment interaction (G × E). The joint data included 730 810 TD records of 87 734 cows and 231 common sires. Random regression TD sire models with fourth-order Legendre polynomials were used to estimate genetic parameters via within- and across-country analyses. Daily heritability estimates of milk yield from within-country analysis were between 0.11 and 0.32, and 0.03 and 0.13 in Luxembourg and Tunisia, respectively. Heritability estimates for 305-day milk yield and persistency (defined as the breeding value for milk yield on DIM 280 minus the breeding value on DIM 80) were lower for Tunisian Holsteins compared with the Luxembourg population. Specifically, heritability for 305-day milk yield was 0.16 for within- and 0.11 for across-country analyses for Tunisian Holsteins and 0.38 for within- and 0.40 for across-country analyses for Luxembourg Holsteins. Heritability for apparent persistency was 0.02 for both within- and across-country analyses for Tunisian Holsteins and 0.08 for within- and 0.09 for across-country analyses for Luxembourg Holsteins. Genetic correlations between the two countries were 0.50 for 305-day milk yield and 0.43 for apparent persistency. Moreover, rank correlations between the estimated breeding values of common sires for 305-day milk yield and persistency, estimated separately in each country, were low. Low genetic correlations are evidence for G × E for milk yield production while low rank correlations suggest different rankings of sires in both environments. Results from this study indicate that milk production of daughters of the same sires depends greatly on the production environment and that importing high merit semen for limited input systems might not be an effective strategy to improve milk production.     

Anesthesia and analgesia of ornamental birds

Pet birds are frequently viewed as difficult patients for anaesthesia. The present paper revises the current anaesthetic procedures for injectable and inhalant anaesthetics. Currently the method of choice for the anaesthesia of pet birds is the isoflurane inhalation anaesthesia. Special emphasis is given to the preanaesthetic preparations. Fasting is shorter for pet birds than for mammals. Anaesthetized birds are at special risk for hypothermia. Methods for the prevention of heat loss are given. The use of analgesics are recommended both for welfare reasons but also because of the possibility to reduce the concentration of inhalation anaesthetics and therefore the amount of possible exposure of personnel to waste gases.     

Validation of several types of noxious stimuli for use in determining the minimum alveolar concentration for inhalation anesthetics in dogs and rabbits

OBJECTIVE: To compare 3 types of noxious stimuli applied to various anatomic areas of anesthetized dogs and rabbits for determination of the minimum alveolar concentration (MAC). ANIMALS: 10 dogs and 10 rabbits. PROCEDURE: Dogs were anesthetized with isoflurane and halothane in a randomized order. Rabbits were anesthetized with isoflurane. The MAC was determined by skin incision on the lateral aspect of the chest; clamping of the tail, paw of the forelimb, and paw of the hind limb; and application of electrical current to the oral mucosa (dogs only), forelimb, and hind limb. The MAC was the end-tidal concentration midway between the value permitting and preventing purposeful movement in response to noxious stimuli. RESULTS: In dogs, mean +/- SEM MAC for isoflurane was 1.27 +/- 0.05% for clamping stimuli, 1.36 +/- 0.04% for oral electrical stimulation, 1.35 +/- 0.04% for electrical stimulation to the limbs, and 1.01 +/- 0.07% for surgical incision. The MAC for halothane was 0.97 +/- 0.03% for tail clamping, 0.96 +/- 0.03% for clamping of the limbs, 1.04 +/- 0.03% for electrical stimulation, and 0.75 +/- 0.06% for surgical incision. In rabbits, MAC for isoflurane was 2.08 +/- 0.02% for clamping stimuli, 2.04 +/- 0.02% for electrical stimulation, and 0.90 +/- 0.02% for surgical incision. The MAC for surgical incision was significantly lower than values for the other methods in both species. CONCLUSIONS AND CLINICAL RELEVANCE: Use of electrical current and clamping techniques resulted in similar MAC values. Surgical incision underestimated MAC values in dogs and rabbits.     

Genetic analysis of longitudinal measurements of performance traits in selection lines for residual feed intake in Yorkshire swine

A 5-generation selection experiment in Yorkshire pigs for feed efficiency consists of a line selected for low residual feed intake (LRFI) and a random control line (CTRL). The objectives of this study were to use random regression models to estimate genetic parameters for daily feed intake (DFI), BW, backfat (BF), and loin muscle area (LMA) along the growth trajectory and to evaluate the effect of LRFI selection on genetic curves for DFI and BW. An additional objective was to compare random regression models using polynomials (RRP) and spline functions (RRS). Data from approximately 3 to 8 mo of age on 586 boars and 495 gilts across 5 generations were used. The average number of measurements was 85, 14, 5, and 5 for DFI, BW, BF, and LMA. The RRP models for these 4 traits were fitted with pen × on-test group as a fixed effect, second-order Legendre polynomials of age as fixed curves for each generation, and random curves for additive genetic and permanent environmental effects. Different residual variances were used for the first and second halves of the test period. The RRS models were fitted with the same fixed effects and residual variance structure as the RRP models and included genetic and permanent environmental random effects for both splines and linear Legendre polynomials of age. The RRP model was used for further analysis because the RRS model had erratic estimates of phenotypic variance and heritability, despite having a smaller Bayesian information criterion than the RRP model. From 91 to 210 d of age, estimates of heritability from the RRP model ranged from 0.10 to 0.37 for boars and 0.14 to 0.26 for gilts for DFI, from 0.39 to 0.58 for boars and 0.55 to 0.61 for gilts for BW, from 0.48 to 0.61 for boars and 0.61 to 0.79 for gilts for BF, and from 0.46 to 0.55 for boars and 0.63 to 0.81 for gilts for LMA. In generation 5, LRFI pigs had lower average genetic curves than CTRL pigs for DFI and BW, especially toward the end of the test period; estimated line differences (CTRL-LRFI) for DFI were 0.04 kg/d for boars and 0.12 kg/d for gilts at 105 d and 0.20 kg/d for boars and 0.24 kg/d for gilts at 195 d. Line differences for BW were 0.17 kg for boars and 0.69 kg for gilts at 105 d and 3.49 kg for boars and 8.96 kg for gilts at 195 d. In conclusion, selection for LRFI has resulted in a lower feed intake curve and a lower BW curve toward maturity.     

Comparison of the Anvajo Vet Fluidlab 1 urine sediment analyzer to manual microscopy and Idexx SediVue analysis for analysis of urine samples from cats and dogs

The Vet Fluidlab 1 (Anvajo), a new urine sediment analyzer for use in veterinary medicine, uses holographic microscopy to detect urine sediment particles in uncentrifuged urine. We compared the performance of the Fluidlab to manual microscopy and Idexx SediVue analysis for the detection of RBC, WBC, epithelial cells (EC), struvite crystals (STR), all crystals (CRY), and casts (CST) in urine samples from cats and dogs. The performance of the Fluidlab for the detection of bacteria was compared to bacterial culture. We included 624 urine samples from feline (238; 38%) and canine (386; 62%) patients; 227 samples had been submitted for bacterial culturing. The sensitivity of the Fluidlab compared to manual microscopy was 92.1% for RBC, 90.1% for WBC, 87.5% for EC, 67.6% for STR, 53.9% for CRY, and 12.5% for CST. Specificity was >97% for STR and CST, 90.0% for CRY, 78.4% for WBC, 59.4% for EC, and 55.1% for RBC. Sensitivities and specificities of the Fluidlab for analytes compared to manual microscopy were found to be similar to those obtained by the Fluidlab compared to SediVue analysis. Miscellaneous materials (e.g., lipid droplets, sperm, cell detritus) seemed to be the main reason for the high false-positive rate in RBC and EC classification by the Fluidlab. Detection of bacteria by the Fluidlab compared to bacterial culture had a sensitivity of 89.8% and a specificity of 72.3%. The performance of the Fluidlab is acceptable for the detection of WBC and bacteria; sensitivity for the detection of CRY and CST, and specificity for the detection of RBC and EC, require improvement.     

Amino acid utilisation by dairy cows. II. Concept of amino acid requirementsUtilisation des acides aminés par les vaches laitières. II. Concept des besoins en acides aminésAminosäureverwertung bei milchkühen. II. Zum konzept des aminosäurenbedarfs

In dairy cows amino acids may be required for four processes: maintenance; as precursors for the synthesis of glucose (gluconeogenesis); for protein deposition in muscle or associated with foetal growth; and for the synthesis of milk protein.Estimates of the protein requirements for maintenance are often conflicting and seem far from accurate. Estimates of the ratio in which essential amino acids are required for maintenance are not yet available.Requirements of amino acids for gluconeogenesis are difficult to estimate. It seems rather unlikely that essential amino acids will be used in significant quantities for gluconeogenesis, even at high milk yields.Protein requirements for pregnancy and muscle growth in dairy cows are relatively low. The ratio in which essential amino acids are supplied in the blood seems adequate for both processes.Amino acid requirements for milk protein synthesis are somewhat higher than the net protein output. This is particularly true for essential amino acids of which, in the mammary gland, a surplus of some 50% needs to be extracted from the blood. The ratio in which essential amino acids are supplied to the mammary gland seems reasonably adequate for milk protein synthesis.     

First genetic data for band-winged grasshoppers (Orthoptera: Acrididae: Oedipodinae) of the Biskra region of Algeria with new records for the country

DNA barcoding represents an objective tool for fast species identification, especially for taxa for which morphological identification is difficult. One current limitation of barcoding is the lack of reference sequences for many groups. While many European and North American countries have started their own barcoding initiatives to generate complete local inventories and databases, such efforts are sparse for African, Asian and South American countries, despite their high biodiversity and comparably poorly explored faunas. Therefore, it is important to start local barcoding efforts in such countries. In this study we performed DNA barcoding for the band-winged grasshoppers of the Biskra province in Algeria, a region of high diversity for this taxon. All specimens were identified morphologically and then barcoded. We generated a total of 47 sequences of the COI gene for 22 morphologically identified species of Oedipodinae, many of which were sequenced for the first time. We present the data in a phylogenetic tree, which suggests monophyly for most genera, but rejects it for Sphingonotus and Vosseleriana. Statistical species delimitation worked well for most genera, except those within the Sphingonotini, likely because these have radiated rather recently. Together with data sourced from the literature we used our new data set to generate an updated list of band-winged grasshoppers for the region. Several species are recorded for the region and for the country for the first time. One species appears to be new to science. Furthermore, we found geographic variation within several more widespread species for which data from other countries were present. We consider the new data as an important resource for future faunistic, ecological and biodiversity studies and point out the importance of local (taxon-specific) barcoding studies.     

The detection of anthelmintic resistance in nematodes of veterinary importance

Before revised World Association for the Advancement of Veterinary Parasitology (WAAVP) guidelines on the detection of anthelmintic resistance can be produced, validation of modified and new methods is required in laboratories in different parts of the world. There is a great need for improved methods of detection of anthelmintic resistance particularly for the detection of macrocyclic lactone resistance and for the detection of resistant nematodes in cattle. Therefore, revised and new methods are provided here for the detection of anthelmintic resistance in nematodes of ruminants, horses and pigs as a basis for discussion and with the purpose that they are evaluated internationally to establish whether they could in the future be recommended by the WAAVP. The interpretation of the faecal egg count reduction test has been modified and suggestions given on its use with persistent anthelmintics and continuous release devices. An egg hatch test for benzimidazole (BZ) resistance is described. A microagar larval development test for the detection of benzimidazole and levamisole resistance provides third stage larvae for the identification of resistant worms. The sensitivity of these two tests can be increased by using discriminating doses rather than LD(50) values. Details are given of a PCR based test for the analysis of benzimidazole resistance in strongyles of sheep and goats, horses and cattle. Although promising for ruminant trichostrongyles, quantitative determination of gene frequency using real time PCR requires further development before PCR tests will be used in the field. Apart from faecal egg count reduction tests there are currently no satisfactory tests for macrocylic lactone resistance despite the great importance of this subject. Except for treatment and slaughter trials there are no validated tests for fasciolicide resistance or for the detection of resistance in cestodes.     

Absorption of equations for non-parents for an animal model with maternal effects and genetic groups

Rules for forming the mixed-model equations for the reduced animal model with all relationships and including maternal effects have been set out by Quaas and Pollak. They also have shown how to simplify the mixed-model equations when genetic group effects are included in the model with what has become known as the Q-P transformation. Westell has given rules for calculating the coefficients for the Q-P transformed equations that are associated with the inverse of the numerator relationship matrix and genetic group effects. Those rules can be extended to include maternal effects and genetic groups for maternal as well as direct effects. As with the rules of Quaas and Pollak for the equations for the reduced animal model, a similar set of rules can be obtained for the genetic groups model after the Q-P transformation. The rules are derived easily by examining the algebraic results of absorbing the direct and maternal breeding value equations for non-parents into the parent breeding value, group and fixed effects equations. These rules involve Westell's rules and the inverse elements of the genetic (co)variance matrix for direct and maternal additive genetic effects. The rules make calculation of breeding values for parents for models including direct and maternal genetic group effects nearly as easy as for models without genetic group effects. Back solution for direct and maternal breeding values of non-parents similarly is as simple as when genetic group effects are not in the model.     

猪抗病育种研究进展

作者对开展抗病育种的必要性、发展过程、抗病的遗传基础、抗病育种方法的现状及存在的问题进行了介绍。其中对MHC、抗病主基因、抗病育种的直接、间接方法、转基因抗病育种进行了重点介绍，提出采用分子标记辅助选择和转基因工程抗病育种是当前和今后抗病育种的主要方向，最后对抗病育种将来的发展前景进行了展望。     

Prevalence and interrelationships of hoof lesions and lameness in Swedish dairy cows

The prevalence of hoof lesions and lameness in 4899 heifers and cows was determined at claw trimming one time in a cross-sectional study on 101 Swedish dairy farms, 1996-1998. The percentage of affected animals was 41% for heel-horn erosion, 30% for sole haemorrhages, 27% for erosive dermatitis, 21% for abnormal claw shape, 14% for white-line haemorrhages, 8.8% for white-line fissures, 8.6% for sole ulcers, 3.3% for double soles, 2.3% for verrucose dermatitis, and 1.8% for interdigital hyperplasia (IH). Seventy-two percent of all animals had at least one hoof lesion. The prevalence of lameness was 5.1%; most hoof lesions did not cause lameness. Differences between herds were substantial; the herd-specific, animal-level prevalence of lesions ranged from 25 to 98% and of lameness from 0 to 33%. Sole haemorrhages were found in all herds. The proportion of variance at the between-herd level was particularly high for heel-horn erosion (62%) and abnormal claw shape (54%). Strong correlations between lesions were found within hooves (and animals), e.g. for heel-horn erosion and dermatitis (Spearman's rank correlation, r(s)=0.36 and 0.37, respectively) and for sole and white-line haemorrhages (r(s)=0.25 and 0.28). Most hoof lesions affected hind and front hooves bilaterally, whereas the correlation between hind and front hooves generally was lower. Herds that ranked high for prevalence of sole ulcer also ranked high for sole haemorrhages and for abnormal claw shape and herds that ranked high for dermatitis also ranked high for heel-horn erosion, verrucose dermatitis and IH. Abnormal claw shape was strongly associated with sole ulcer (r(s)=0.41 at cow level)-suggesting the importance of maintaining a correct claw shape for the prevention of hoof-horn lesions.     

Comparison of intradermal testing and serum testing for allergen-specific IgE using monoclonal IgE antibodies in 84 atopic dogs

OBJECTIVE: To compare an ELISA measuring serum allergen-specific IgE with intradermal skin testing in canine atopic dermatitis. PROCEDURE: Eighty-four dogs with the clinical diagnosis of atopic dermatitis underwent intradermal skin testing and serum testing for allergen-specific IgE. Tests were performed in a blinded fashion. Positive reactions were compared and the sensitivity and specificity of the serum test (using intradermal skin test as the standard) were determined overall and for individual allergen groups (grass pollens, weed pollens, tree pollens, house dust mites and fleas). RESULTS: The sensitivity of the ELISA overall was 90.4%. Evaluating the individual allergen groups, the sensitivity for dust mite hypersensitivity was 95.1%, for fleas 85.4%, for tree pollens 84.3%, for grass pollens 95.1% and for weed pollens 96.4%. The specificity was 91.6% overall, for dust mites 96.3%, for fleas 92.7%, for tree pollens 95.2%, for grass pollens 94% and for weed pollens 80.7%. CONCLUSION: The evaluated ELISA seemed reliable for the diagnosis of atopy in practice and can be recommended as a screening test prior to intradermal skin testing or for use in dogs when immunotherapy is not a therapeutic option.     

Determination of the incidence of Salmonella spp., Campylobacter jejuni, and Clostridium perfringens in wild birds near broiler chicken houses by sampling intestinal droppings

Several methods were evaluated for collecting fecal and intestinal samples from wild birds found near broiler chicken houses. A few intestinal samples and cloacal swabs were obtained from European starlings and house sparrows. Most of the samples collected consisted of wild bird droppings found on or near the houses. Samples were collected from each of four farms of a broiler integrator during a grow-out cycle: a cycle in the summer for farm A, fall for farm B, and spring, summer, fall, and winter for farms C and D. Of the 25 wild bird intestinal and fecal samples collected from a broiler house on farm A during a grow-out cycle in July-August 1997, 24% were positive for Salmonella spp., 4% for Campylobacter jejuni, and 28% for Clostridium perfringens. Of the nine fecal samples collected from broiler house B in a grow-out cycle in September-November 1997, 33% were positive for Salmonella spp., 11% for C. jejuni, and 22% for C. perfringens. For farms C and D, of the 23 samples collected in March-April 1998, 0 were positive for Salmonella spp., 11% for C. jejuni, and 52% for C. perfringens; of 27 samples collected in June-July 1998, 4% were positive for Salmonella spp., 0 for C. jejuni, and 13% for C. perfringens; of 24 samples collected in August-October 1998, 14% were positive for Salmonella spp., 5% for C. jejuni, and 4% for C. perfringens; of 14 samples collected December 1998-January 1999, 0 were positive for Salmonella, 50% for C. jejuni, and 14% for C. perfringens. The incidence of these bacterial enteropathogens in wild birds near the broiler chicken houses suggests that wild birds that gain entry to poultry grow-out houses have the potential to transmit these pathogens to poultry.     

Stimulated single fibre electromyography in normal dogs

A technique for the evaluation of neuromuscular transmission using single fibre electromyography was developed for the peroneus longus muscle of dogs. Individual muscle fibre action potentials were recorded in 10 dogs, with a specialised needle electrode, during repetitive axon-al stimulation at the motor point of the right peroneus longus muscle. Variability in latency from stimulus artefact to action potential was evaluated for 50 to 100 consecutive discharges for several fibres in the muscle of each dog. Latency variability (jitter) was expressed as the mean of consecutive differences (MCD) in latency for each muscle fibre. A mean of MCDS was calculated for the muscle of each animal. The upper limits of normal for the peroneus longus suggested by this study are 30 us (for individual muscle fibres) and 19 μs (for mean of group of fibres).     

实验条件下山羊绒洗净因素对口蹄疫病毒的影响

模拟我国和蒙古国洗净羊绒企业山羊绒洗涤工艺,进行了不同的洗涤水温及作用时间、不同的烘干温度及作用时间对口蹄疫病毒灭活作用的检测。结果表明,水温在64℃以下处理60min不能灭活羊绒中的口蹄疫病毒NM-zg99毒株,65℃处理60min、66℃处理45min、75℃处理10min、80℃处理5min能灭活羊绒中的口蹄疫病毒;高温烘干对羊绒中口蹄疫病毒的灭活与温度和作用时间密切相关,70℃处理约35min、75℃处理约25min能灭活口蹄疫病毒,80～90℃处理20min、95～105℃处理15min、110℃处理10min能使口蹄疫病毒失活。该试验结果为我国制定进口洗净毛、绒检验标准提供了参考数据,并对洗净羊绒企业改进羊毛、绒洗涤工艺具有指导意义。     

Threshold-linear versus linear-linear analysis of birth weight and calving ease using an animal model: I. Variance component estimation.

Birth weight and calving difficulty were analyzed with Bayesian methodology using univariate linear models, a bivariate linear model, a threshold model for calving difficulty, and a joint threshold-linear model using a probit approach. Field data included 26,006 records of Gelbvieh cattle. Simulated populations were generated using parameters estimated from the field data. The Gibbs sampler was used to obtain estimates of the marginal posterior mean and standard deviation of the (co)variance components, heritabilities, and correlations. In the univariate analyses, the posterior mean of direct heritability for calving difficulty was .23 with the threshold model and .18 with the linear model. Maternal heritabilities were .10 and .08, respectively. In the bivariate analysis, posterior means of direct heritability for calving difficulty were .21 and .18 for the bivariate linear-threshold and linear-linear model, respectively. Maternal heritabilities were .09 and .06, respectively. Direct heritability for birth weight was .25 for the univariate model and .26 for bivariate models. Maternal heritability was .05 for the linear-threshold model and the univariate model and .06 for the bivariate linear model. Genetic correlation between direct genetic effects in both traits was .81 for the linear-threshold model and .79 for the bivariate linear. Residual correlation was .35 for the bivariate linear model and .50 for the bivariate linear-threshold. A simulation study confirmed that the posterior mean of the marginal distribution was suitable as a point estimate for univariate threshold and bivariate linear-threshold models.