Comparison of the effects of injections of nortestosterone phenylpropionate at single and multiple sites in cattle on the detection of its residues in plasma, urine and bile

The synthetic androgen 17 beta-19-nortestosterone (beta-NT) has been used illegally as a growth promoter in cattle production in the European Union. The elimination of beta-NT and its metabolites in plasma and urine was studied in cattle which had received intramuscular injections of its phenylpropionate ester (NTPP) at either single or multiple sites at a dose rate of 1 mg/kg bodyweight. In both groups, the plasma concentrations of beta-NT, measured by enzyme immunoassay, were consistently greater than the assay's limit of quantification (0.24 ng/ml) during days 1 to 7 of the study. The mean (sd) maximum plasma concentration (Cmax) was significantly greater in the multiply injected animals (4.4 [0.48] v 2.7 [0.15] ng/ml), but other plasma pharmacokinetic parameters, AUC, CL, T1/2 beta, Tmax and MRT, were not significantly different in the two groups. The equivalent urinary concentrations exceeded the limit of quantification of the assay (4.5 ng/ml) for up to 24 days after injection. In a second study, the biliary concentrations of beta-NT and its 17 alpha-epimer (alpha-NT) were measured by gas chromatography-high resolution mass spectrometry after cattle were injected intramuscularly at either single or multiple sites with NTPP. Only alpha-NT was detected in bile for up to 62 days after injection at concentrations above the limit of quantification of the assay (0.7 ng/ml). It is concluded that in some animals, intramuscular injections of NTPP at several sites may decrease the period after injection during which free beta-NT and its metabolites are detectable in plasma and urine. After the injection of NTPP, alpha-NT was detected in bile for longer than it was detected in plasma or urine.     

Monitoring and identification of residues of anabolic preparations in slaughtered cattle by HPLC with diode array detection

The new combination of isocratic high performance liquid chromatography (HPLC) with on line UV spectrum detection via a diode array configuration has been applied to the detection and identification of anabolics present in application sites of cattle. Combination of the characteristic retention time in the HPLC chromatogram and a comparison of the full spectrum between 190-400 nm of the anabolic components with that of a standard resulted in a very reliable identification. By means of this method 117 samples of application sites were investigated for the presence of anabolic residues. Of the xenobiotic anabolics , 19-nortestosterone (NT) was found most frequently (in 96 cases), whereas diethylstilbestrol (DES) was found in only 11 cases. In all samples the identification of NT and DES was confirmed by high resolution gas chromatography-mass spectrometry (GCMS).     

骨桥蛋白在长白公猪生殖细胞中的表达及其与繁殖性能的相关性

本试验旨在研究骨桥蛋白（osteopontin,OPN）在长白公猪生殖细胞中的表达和定位,并探究其与公猪繁殖性能的相关性。试验采集了长白公猪精液和不同阶段（3日龄、3月龄、6月龄和12月龄）的睾丸组织,通过蛋白印迹的方法检测OPN蛋白在精液和不同月龄睾丸中的表达,通过免疫组化的方法对OPN蛋白在公猪睾丸细胞中进行定位;同时,根据配种胎次≥ 20胎,3次配种公猪为同一头的标准,筛选并采集17头长白种公猪精液,统计相对应的1 388头母猪的生产成绩,计算得到公猪繁殖性能指标（包括窝产总仔数、窝产活仔数、分娩率和繁殖力）。低温离心精液分离得到精子和精浆,丙酮法提取精浆蛋白,Lysis buffer方法提取精子蛋白,最后运用BCA和ELISA的方法检测精子和精浆中OPN蛋白的含量,分析OPN蛋白与公猪繁殖性能的相关性。蛋白印迹结果显示,OPN在精子、精浆和各月龄阶段的长白公猪睾丸中均以两种形式表达（67.4和33.7 ku）,且67.4 ku的形式在3月龄公猪睾丸中表达量最高;免疫组化的结果显示,OPN在长白公猪的初级精母细胞、次级精母细胞和精子细胞中表达,在精母细胞、支持细胞和间质细胞中无表达;BCA和ELISA结果显示,精子中的OPN蛋白含量是精浆中的7倍（P<0.05）,精液中的OPN蛋白与公猪窝产活仔数显著正相关（P<0.05）。本试验结果表明,OPN在各阶段的长白公猪睾丸中都有表达,且在精子和精浆中也有表达,这可能与公猪的繁殖性能有关,从而为后期OPN蛋白在公猪受精力的研究奠定基础。     

Virulence genes and plasmid profiles in Rhodococcus equi isolates from domestic pigs and wild boars (Sus scrofa) in Brazil

The virulence genes and plasmid profiles of 23 Rhodococcus equi isolates from 258 lymph nodes from domestic pigs (129 nodes with lesions and 129 without lesions) and 120 lymph nodes from slaughtered wild boars (60 nodes with lesions and 60 without) were characterized. R. equi was obtained from 19 lymph nodes of domestic pigs, 17 with, and two without lesions, and from four lymph nodes with lesions, from wild boars. The 23 isolates were tested for the presence of vapA and vapB genes, responsible for the 15–17 and 20 kDa virulence-associated proteins, respectively, by PCR in order to characterize as virulent (VapA), intermediately virulent (VapB) and avirulent. Plasmid DNAs were isolated and analyzed by digestion with restriction endonucleases to estimate size and compare their polymorphisms. Of the 19 domestic pigs strains, seven (36.8%) were avirulent and 12 (63.2%) were intermediately virulent, with the intermediately virulent isolates being plasmid types 8 (8 isolates), 10 (2 isolates), 1 (1 isolate) and 29 (1 isolate). The plasmid type of four strains isolated from wild boars was also intermediately virulent type 8. None of the domestic pigs and wild boar isolates showed the vapA gene. These findings demonstrate a high occurrence of plasmid type 8 in isolates from pigs and wild boars, and the similarity of plasmid types in the domestic pigs, wild boars and human isolates in Brazil.     

Genetic profile and serosurvey for virus infections of Japanese wild boars in Shikoku Island

To estimate the genetic background of Japanese wild boars inhibiting the 4 prefectures of Shikoku Island (Kagawa, Tokushima, Kouchi and Ehime), we examined haplotypes of mitochondrial DNA (mtDNA) and genotypes of the nuclear glucosephosphate isomerase-processed pseudogene (GPIP) in 189 wild boars. Of the 8 different mtDNA haplotypes (J5, J10, J12, J13, J15, J19, J20 and E33) detected in Shikoku Island, the first to be identified were J19 and J20 (of Japanese wild boar lineage) and E33 (of European domestic pig lineage). The presence of haplotype E33 indicates local crossbreeding between wild boar and escaped domestic pigs and/or crossbred Inobuta. Four kinds of the GPIP genotypes were detected from 189 wild baors in Shikoku Island, but no European GPIP alleles were found. In 113 wild boars, no antibodies against Classical Swine Fever or Aujeszky's disease were detected, suggesting that they had not been exposed to those pathogens.     

Epidemiological study on porcine circovirus type 2 (PCV2) infection in the European wild boar (Sus scrofa)

Porcine circovirus type 2 (PCV2) is considered as the causative agent of postweaning multisystemic wasting syndrome (PMWS) in domestic pigs, where the virus is ubiquitous as evidenced by serological surveys. We present the results of the first nationwide sero-survey on the presence of PCV2 antibodies in European wild boars, and report the first PMWS case in a wild boar from Spain. Sera from 656 hunter harvested wild boars from 45 different geographical sites and 22 additional imported animals were analysed by means of an immunoperoxidase monolayer assay (IPMA). We also examined the tissues from 55 healthy and one diseased wild boars for the presence of PCV2 nucleic acid and PMWS lesions by in situ hybridisation and histopathology, respectively. Additionally, abundance estimates of wild boars and field interviews were carried out on 30 sampling sites. The prevalence of medium to high PCV2 serological titres among the examined wild boars was 47.89 +/- 1.9%. Seropositive wild boars appeared in all but one of the geographical regions analysed. Seroprevalence and titre of PCV2 antibodies were closely related to the management of the wild boar populations. Wild boars from intensively managed, farm-like populations had higher prevalence than wild boars living in more natural situations. The effect of wild boar abundance and management on PCV2 antibody prevalence was further evidenced by the high correlation existing between the relative abundance estimates of animals and the percentage of wild boars with medium to high levels of PCV2 antibodies. PCV2 nucleic acid was detected in the tissues of three wild boars. One of these was diagnosed as PMWS. The results, in addition to information on piglet mortalities, suggest a potential role of PMWS in piglet mortality in intensively managed wild boar populations.     

Detection of Lawsonia intracellularis in wild boar and fallow deer bred in one game enclosure in the Czech Republic

The prevalence of Lawsonia intracellularis between wild boar (Sus scrofa) and fallow deer (Dama dama) bred in one game reserve was investigated using the nested PCR method. In the study, 88 clinically healthy wild boars of different age categories and two fallow deer bagged in the game reserve were examined. Lawsonia intracellularis was demonstrated in the mucous membrane of the intestine of eight (9.1%) wild boars and one fallow deer. Of the nine wild boar whose tissues of corresponding lymph nodes were examined in addition to the mucous membrane of the ileum, one tested positive for the microorganism. A relationship between the occurrence of L. intracellularis and age of wild boar was demonstrated. Because wild boar and fallow deer are bred together in one game reserve, the possibility of inter-species transfer of L. intracellularis should be borne in mind.     

野猪附红细胞体病的诊断及防治

对河北省某野猪养殖基地病死猪进行临床诊断和实验室诊断，通过采取血液直接压片镜检，血液染色镜检，细菌检查，细菌培养和猪瘟抗体检测，证实该野猪养殖基地发病为野猪附红细胞体病。建议其使用多西环素饮水，并取得了良好的效果。     

Clinical, virologic, and histopathologic observations of induced porcine parvovirus infection in boars

Twelve 8- to 12-month-old crossbred boars were inoculated with a virulent strain (NADL-8) of porcine parvovirus (PPV). Hemicastrations were performed on 6 boars 3, 7, 10, 14, 21, and 28 days after an IM injection of 10(8) median cell culture infectious dose (CCID50) of PPV (n = 3) or injection of 10(7.4) CCID50 given intratesticularly (IT, n = 3). Noninfected cell culture medium (0.25 ml) was injected into each testicle of a 7th boar (IT inoculated control). Virus or viral antigen was detected in testicular and epididymal tissues up to 14 days after inoculation. Direct immunofluorescence indicated that viral antigen was mainly associated with the vasculature of the interstitium. Microscopic lesions were not evident in the testicles and epididymides of IM inoculated boars. Acute-to-chronic testicular degeneration was evident in the IT inoculated boars, as well as in the IT inoculated control boar. Six boars were inoculated IM or orally/nasally with 10(7.9) CCID50 of PPV. Semen was collected twice weekly for 8 weeks after inoculation. Virus was not detected in any ejaculates. Semen also was collected from 4 boars for 5 weeks before inoculation, and preinoculation and post-inoculation semen quality was compared. Pronounced changes in sperm output, ejaculate volume, motility, or morphologic defects were not observed. The reproductive consequences of experimental PPV infection in boars were minimal because reproductive function was unaffected and venereal transmission of PPV was not detected.     

Detection and duration of porcine reproductive and respiratory syndrome virus in semen, serum, peripheral blood mononuclear cells, and tissues from Yorkshire, Hampshire, and Landrace boars.

Because transmission of porcine reproductive and respiratory syndrome virus (PRRSV) can occur through boar semen, it is important to identify persistently infected boars. However, even for boars given the same PRRSV strain and dose, variability in the duration of viral shedding in semen has been observed, suggesting that host factors are involved in PRRSV persistence. To determine whether there are host genetic factors, particularly litter and breed differences related to the persistence of PRRSV, 3 litters from 3 purebred swine breeds were used for this study. It was also determined whether PRRSV could be detected for a longer period of time in serum, semen, or peripheral blood mononuclear cells (PBMC) and if PRRSV could still be detected in tissues after these antemortem specimens were PRRSV negative for a minimum of 2-3 weeks. Three Hampshire, 3 Yorkshire, and 2 Landrace PRRSV-naive boars were obtained and inoculated intranasally with a wild-type PRRSV isolate (SD-23983). All boars within each breed were from the same litter, and litters were within 9 days of age. Serum and PBMC were collected twice weekly from each boar and analyzed for the presence of PRRSV by virus isolation and the polymerase chain reaction (PCR). Serum was also used to obtain virus neutralization titers and enzyme-linked immunosorbent assay S/P values. Semen was collected twice weekly from 7 of 8 boars and analyzed by PCR. After all specimens were PRRSV negative for a minimum of 2-3 weeks, each boar was euthanized, and 21 tissues plus saliva, serum, feces, and urine were collected. All postmortem specimens were evaluated by virus isolation. Specimens that were PRRSV negative by virus isolation were then evaluated by PCR. The mean number of days (+/-SD) for the duration of PRRSV shedding in semen was 51+/-26.9 days, 7.5+/-4.9 days, and 28.3+/-17.5 days for Landrace, Yorkshire, and Hampshire boars, respectively. Because of small sample sizes and large SDs, the differences in duration of PRRSV shedding in semen between breeds were not considered significant. However, the trend suggested that Yorkshire boars were more resistant to PRRSV shedding in semen than were Landrace boars, requiring further investigation using a larger numbers of boars. PRRSV was detected for a longer period in semen than in serum or PBMC in 4 of 7 boars. Viremia could be detected for a longer period in serum than in PBMC in 6 of 8 boars. After a minimum of 2-3 weeks of PRRSV-negative serum, semen, and PBMC, PRRSV could still be detected in the tonsil of 3 of 8 boars by virus isolation, indicating that boars still harbor PRRSV within the tonsil even though antemortem specimens are PRRSV negative.     

Prevalence of Toxoplasma gondii and Neospora caninum antibodies in wild boars in the Czech Republic

Sera collected from hunter-killed wild boars (Sus scrofa) during 1999-2005 from seven different regions of the Czech Republic were assayed for antibodies to Toxoplasma gondii by indirect fluorescence antibody test and to Neospora caninum by competitive-inhibition enzyme-linked immunosorbent assay and by indirect fluorescence antibody test. Antibodies to T. gondii were detected in 148 (26.2%) of 565 wild boars with serum dilutions of 1:40 in 40, 1:80 in 40, 1:160 in 27, 1:320 in 19, 1:640 in 18 and 1:1280 in 4 wild boars. Antibodies to N. caninum were detected in 102 (18.1%) of 565 wild boars with 30.1-94.6% inhibition in ELISA; statistical significant differences were observed between sampling regions, ranging from 0% to 31.8%. Sera, positive in ELISA, were examined in IFAT; 58 of 102 (56.9%) were positive with titres 1:40-1:160. Mixed infection (concurrent presence of both T. gondii and N. caninum antibodies) was found in 38 wild boars. It is the first report of antibodies to N. caninum in wild boar. Serological results indicate a common exposure to T. gondii and to N. caninum among wild boars in the Czech Republic.     

不同品种、月份、月龄及采精间隔对猪精液品质的影响

为研究不同品种、采精月份、采精月龄和采精间隔等因素对加系公猪精液品质的影响,以及品种、初次采精周龄对精液质量稳定性的影响,本研究以江西某种公猪站79头加系大白猪、长白猪、杜洛克猪种公猪为试验群体,收集2018年12月至2020年12月3 921条精液采集与精液质量数据,通过混合线性模型与方差分析探究各因素对精液量、精液密度、精子活力、总精子数及其稳定性的影响。结果显示,从不同品种对精液质量的影响来看,长白猪精液量和总精子数均高于大白猪、杜洛克猪,但杜洛克猪精液密度高于长白猪、大白猪,杜洛克猪精子活力最低;从不同月份来看,1~3月采精精液密度最高,4~6月采精精子活力最高,10~12月采精精液量和总精子数最高,精液量呈现秋冬多、春夏少的季节变化规律。公猪不同月龄采精,精液质量指标也存在差异,月龄越小精液量越低,但精液密度偏高,精子活力相对较好,在19~24月龄黄金期总精子数最高。不同采精间隔对精液质量有较大影响,采精间隔越长,精液量、精液密度、精子活力和总精子数相对较好,采精间隔为5 d时综合性能最佳,但过长的采精间隔导致精子活力降低。品种影响总精子数稳定性,长白猪、大白猪总精子数稳定性显著优于杜洛克猪（P<0.05）。本研究结果表明,品种、采精月份、采精月龄和采精间隔均会影响公猪精液质量,关注这些因素有助于公猪站制定更完善的生产计划,提高公猪利用率。     

Improvement of the developmental ability of nuclear transfer embryos by using blastomeres from in vitro fertilized embryos selected according to the early developmental stage and cell division status as donor cells in cattle

This study was conducted to improve the developmental ability of nuclear transfer (NT) embryos by using blastomeres from in vitro fertilized (IVF) embryos with high quality as donor cells. The IVF embryos selected at the 2-cell stage at 24-h postinsemination (hpi) and again at the ≥8-cell stage at 48 hpi (Selected-IVF-embryos) showed the highest blastocyst formation rate among embryos. When blastomeres from the Selected-IVF-embryos (Selected-NT group) or Nonselected-IVF-embryos (Non-selected-NT group) were used as donor cells for NT, the blastocyst formation rate in the Selected-NT group (25.6%) was significantly higher than that in the Non-selected-NT group (13.5%). When blastomeres from the Selected-IVF-embryos at 108 (contained many cells before cell division) and 126 hpi (contained many cells immediately after cell division) were used as donor cells for NT (108- and 126-NT groups, respectively), the 126-NT group showed a significantly higher blastocyst formation rate (32.1%) than the 108-NT group (16.8%). Embryo transfer of blastocysts in the 126-NT group showed that 11 of 23 recipients became pregnant; nine calves were obtained. For the NT embryos reconstructed using in vivo derived embryos, 9 of 20 recipients became pregnant; seven calves were obtained. These results indicate that the blastocyst formation rate of NT embryos can be improved by using blastomeres from IVF embryos selected at the early developmental stage, especially immediately after cell division, and that the resultant NT embryos have a high developmental ability to progress to term that is comparable to NT embryos reconstructed using in vivo derived embryos.     

Multivariate Analyses for Determining the Association of Field Porcine Fertility With Sperm Motion Traits Analysed by Computer‐Assisted Semen Analysis and With Sperm Morphology

This study investigates the association of semen traits with boar fertility. The fertility outcome (farrowing rate – FR and total piglets born – TB) of 14 boars was obtained from a field trial conducted during 10 week of breeding period on a commercial farm using multiparous sows (n = 948) through single‐sire mating with 2 × 10⁹ motile sperm cells per artificial insemination (AI) dose. Sperm motion parameters, evaluated with computer‐assisted semen analysis system in raw and stored semen at 17°C for 240 h, in addition to morphological sperm defects, measured on the collection day, were included in the analysis to determine which semen traits were important to discriminate the fertility potential of ejaculates from these boars. The data underwent multivariate cluster, canonical and discriminant analyses. Four clusters of boars were formed based on fertility outcome. One boar, with the lowest FR and TB values (89.7% and 11.98), and two boars, with the highest FR and TB values (97.8% and 14.16), were placed in different clusters. The other boars were separated in two distinct clusters (four and seven boars), including boars with intermediate TB (12.64 and 13.22) but divergent values for FR (95.9% vs 91.8%). Semen traits with higher discriminatory power included total motility, progressive motility, amplitude of lateral head displacement and cytoplasmatic droplets. Through multivariate discriminant analysis, more than 80% of the 140 ejaculates were correctly classified into their own group, showing that this analysis may be an efficient statistical tool to improve the discrimination of potential fertility of boars. Nevertheless, the validation of the relationship between fertility and semen traits using this statistical approach needs to be performed on a larger number of farms and with a greater number of boars.     

Steroid hormone pathways in the pig, with special emphasis on boar odor: a review

Although castration of male pigs grown for meat production has long been a commercial practice in order to eliminate an undesirable odor emanating from the meat upon heating, intact males (boars) grow faster, utilize feed more efficiently and produce leaner carcasses. This review outlines the biochemical pathways of steroid hormone formation in the pig, placing special emphasis on the C19-delta 16-steroids, which have been shown to produce the "urine- or perspiration-like" odor of boar meat. Analytical methods currently available for quantitation of the C19-delta 16-steroids are also reviewed, including gas chromatography-mass spectrometry, radioimmunoassays and enzyme-linked-immuno-absorbent-assays (ELISA). Finally, methods for preventing boar odor are discussed, such as environmental methods of rearing boars, genetic selection against boar odor and autoimmunization against C19-delta 16-steroids. Autoimmunization techniques appear to offer the most promise for inhibiting production of the compounds responsible for boar odor in male pigs raised for meat production, while still maintaining the advantages of improved efficiency and greater leanness.     

Glasser's disease and prevalence of subclinical infection with Haemophilus parasuis in swine in southern Ontario

Glasser's disease accounted for less than 1% of total swine mortalities in an 11 year retrospective postmortem survey of swine submissions at three provincial government diagnostic laboratories in southern Ontario. However, Glasser's disease was suspected in 17 of 83 boar mortalities at the Record of Production Boar Test Station between 1983 and 1985 and was much more common in specific-pathogen-free (SPF) boars than in conventional boars. The prevalence of the causative organism, Haemophilus parasuis, was determined for 19 SPF herds in Ontario classified as "Excellent" under the Ontario Swine Herd Health Policy. Nasal swabs from two-month-old pigs were cultured on chocolate agar containing 1.5 mug/mL lincomycin, 5 mug/mL bacitracin, and 0.1 mug/mL crystal violet. Three herds were negative for H. parasuis infection; 16 herds contained clinically healthy carrier pigs.     

香猪生殖器官的发育及血浆雌二醇和睾酮含量变化

测试验定了初生、10、20、30、90、150和210日龄香猪公母猪的生殖器官及其血浆雌二醇和睾酮浓度。结果表明,香猪公猪的生殖器官发育较早,母猪生殖器官发育较迟。90日龄时,公猪睾酮水平达3273±1455pg/ml,母猪雌二醇水平也开始上升。发现公猪血浆中查得较母猪高的雌二醇水平。     

Basic reproduction number of African swine fever in wild boars (Sus scrofa) and its spatiotemporal heterogeneity in South Korea

BackgroundAfrican swine fever (ASF) is a hemorrhagic fever occurring in wild boars (Sus scrofa) and domestic pigs. The epidemic situation of ASF in South Korean wild boars has increased the risk of ASF in domestic pig farms. Although basic reproduction number (R₀) can be applied for control policies, it is challenging to estimate the R₀ for ASF in wild boars due to surveillance bias, lack of wild boar population data, and the effect of ASF-positive wild boar carcass on disease dynamics.ObjectivesThis study was undertaken to estimate the R₀ of ASF in wild boars in South Korea, and subsequently analyze the spatiotemporal heterogeneity.MethodsWe detected the local transmission clusters using the spatiotemporal clustering algorithm, which was modified to incorporate the effect of ASF-positive wild boar carcass. With the assumption of exponential growth, R₀ was estimated for each cluster. The temporal change of the estimates and its association with the habitat suitability of wild boar were analyzed.ResultsTotally, 22 local transmission clusters were detected, showing seasonal patterns occurring in winter and spring. Mean value of R₀ of each cluster was 1.54. The estimates showed a temporal increasing trend and positive association with habitat suitability of wild boar.ConclusionsThe disease dynamics among wild boars seems to have worsened over time. Thus, in areas with a high elevation and suitable for wild boars, practical methods need to be contrived to ratify the control policies for wild boars.     

Incidence of boar taint in Swedish Landrace and Yorkshire boars

Boar taint in 500 Swedish Landrace and Yorkshire boar carcasses was tested by smelling fat samples heated on the tip of a soldering iron at 150°C. About 40% of the boars were scored as non-tainted; in another 40%, the judges were unsure whether taint was present or not. Boar taint was judged present in only 20% of the boars.The effects of weight and sex on boar taint were studied in approx. 275 boars, barrows and gilts slaughtered at 70, 90, 110 and 130 kg live weight. The number of boars scored as tainted increased with weight, but weight did not affect the level of taint in all boars. When the taste of boar meat and fat was compared to castrates, no differences were found in 80% of comparisons at 70 or 90 kg.The effect of weight on boar taint was studied in 69 boars reared on ad libitum or restricted feed. Biopsies were taken, by a needle biopsy technique, at 70, 90 and 100 kg live weight. The incidence of boar taint did not increase from 70 to 100 kg when boars were on restricted feed, but the weight effect was significant and linear at the ad libitum feeding level. The cause was probably an interaction between physiological development, age and weight of the boars.