猪重要病毒性病原多重PCR检测方法建立及应用

本试验针对当前对养猪业危害严重的猪瘟病毒(CSFV)、猪繁殖与呼吸综合征病毒(PRRSV)、猪圆环病毒2型(PCV2)、伪狂犬病病毒(PRV)和猪细小病毒(PPV),分别建立了检测CSFV和PRRSV的双重RT-PCR方法和检测PCV2、PRV及PPV的多重PCR方法。所建立的方法对CSFV、PRRSV、PCV2、PRV和PPV核酸的检出量分别为7.5 pg/μL、14.2 pg/μL、6.9 pg/μL、9.2 pg/μL和8.6 pg/μL。应用建立的方法分别对陕西省的陕南、陕北、关中等地区部分猪场采集的118份血清进行病毒检测。5种病毒的检出率分别是,CSFV为4.23%(5/118),PRRSV为22.01%(26/118),PCV2为15.25%(18/118),PRV为22.88%(27/118),从血清样品中未检测到PPV。本研究建立的检测RNA病毒双重RT-PCR和DNA病毒的多重PCR方法,为猪主要病毒其快速检测提供了可选择方法。     

Seroprevalence and associated risk factors of important pig viral diseases in Bhutan

A cross-sectional serological study was conducted in Bhutan between October 2011 and February 2012 to determine the prevalence of antibodies to classical swine fever virus (CSFV), porcine reproductive and respiratory syndrome virus (PRRSV), porcine circovirus type 2 (PCV2), swine influenza virus (SIV) subtype H1N1 and Aujeszky's disease virus (ADV). Furthermore, risk factors for the seropositive status were investigated.     

A case of cephalothoracopagus in sheep in Trinidad and Tobago

A case of cephalothoracopagus in sheep complicated with several defects of skeletal, cardiovascular, respiratory, gastrointestinal, and urogenital systems is reported.     

Seroepidemiology of Toxoplasma gondii in dogs in Trinidad and Tobago

A cross-sectional study was conducted to determine the seroprevalence of Toxoplasma gondii agglutinins and to investigate the relationship between various risk factors and occurrence of toxoplasmosis in dogs in Trinidad. Of a total 250 dogs, comprising domestic, hunting and stray dogs, 80 (32.0%) were positive for T. gondii agglutinins at a titre of > or =1:32 using a latex agglutination test. Stray dogs (60.5%) had statistically significantly higher (P<0.001) seroprevalence for toxoplasmosis than hunting dogs (30.5%) and domestic dogs (25.5%). Amongst dogs whose ages were known, the prevalence of toxoplasmosis was significantly highest (P=0.037) in dogs in the >2-3 years age group compared with other age groups. Dogs that consumed home-cooked foods had a seroprevalence of 32.9% compared with those fed commercial dog foods (17.2%) and dogs fed both home-cooked and commercial foods (21.0%). However, the difference was not statistically significant (P>0.05; chi(2)). The rather high prevalence of toxoplasmosis in stray dogs is a good indication of the extent of the infection in the environment.     

Medicinal plants used for dogs in Trinidad and Tobago

This paper documents ethnoveterinary medicines used to treat dogs in Trinidad and Tobago. In 1995, a 4-stage process was used to conduct the research and document the ethnoveterinary practices. Twenty-eight ethnoveterinary respondents were identified using the school-essay method, which is a modified rapid rural appraisal (RRA) technique. Semi-structured interviews were held with these respondents as well as with 30 veterinarians, 27 extension officers and 19 animal-health assistants and/or agricultural officers, and the seven key respondents that they identified. The final step involved hosting four participatory workshops with 55 of the respondents interviewed to discuss the ethnoveterinary data generated from the interviews and to determine dosages for some of the plants mentioned. Supplementary interviews were conducted in 1997 and 1998.

Seeds of Carica papaya, and leaves of Cassia alata, Azadirachta indica, Gossypium spp., Cajanus cajan and Chenopodium ambrosiodes are used as anthelmintics. The anthelmintics Gossypium spp. and Chenopodium ambrosiodes are the most frequently used species. Crescentia cujete pulp, Musa spp. stem exudate, the inside of the pods of Bixa orellana, leaves of Cordia curassavica and Eclipta alba plant tops are used for skin diseases. Musa spp. stem exudate, seeds of Manilkara zapota, Pouteria sapota and Mammea americana and leaves of Cordia curassavica, Scoparia dulcis and Nicotiana tabacum are used to control ectoparasites. Dogs are groomed with the leaves of Cordia curassavica, Bambusa vulgaris and Scoparia dulcis. Psidium guajava buds and leaves and the bark of Anacardium occidentale are used for diarrhoea. Owners attempt to achieve milk let-down with a decoction of the leaves of Stachytarpheta jamaicensis. The plant uses parallel those practised in human folk medicine in other Caribbean countries and in other tropical countries.     

Seroprevalence of Lawsonia intracellularis in different swine populations in 3 provinces in Canada

Porcine proliferative enteropathy caused by Lawsonia intracellularis is an important enteric disease in swine throughout the world. Information regarding the distribution of this pathogen in Canadian swine herds would be beneficial for the creation of control protocols. Pigs from Ontario, Quebec, and Alberta were tested by using an indirect immunofluorescence assay for antibodies to L. intracellularis. Pig seroprevalence was calculated as the proportion of pigs positive from total pigs tested in the targeted population. Seroprevalence (+/- standard error [s(x)]) in market hogs in Ontario from farrow-finish (FF) farms and finishing (FIN) farms were significantly different at 77% (s(x) = 7%) and 29% (s(x) = 15%), respectively. Seroprevalence for sows and gilts in FF and farrowing and nursery (FAR + NUR) farms in Ontario were 90% (s(x) = 3%) and 93% (s(x) = 6%), respectively. Seroprevalence in breeding females in Quebec from FF and FAR farms was 82% (s(x) = 5%) and 87% (s(x) = 3%), respectively. Seroprevalence (57%, s(x) = 8%) in finishing pigs in Alberta from FF farms was significantly different from that of multisite (MS) farms and FIN farms, 6% (s(x) = 6%) and 9% (s(x) = 5%), respectively. Lawsonia intracellularis appears to be widespread in Canada and the seroprevalence on FF farms is higher than that on FIN and MS farms, possibly due to the presence of breeding females or management differences.     

Seroprevalence of porcine circovirus type 2 in swine populations in Canada and Costa Rica

Porcine circovirus (PCV) was recently divided into 2 antigenically distinct types that differ (65% amino acid identity) in the protein encoded by open reading frame 2 (ORF2). Porcine circovirus 1 is apparently non-pathogenic and, in contrast, PCV2 is associated with porcine multisystemic wasting syndrome (PMWS). Our objective was to determine the extent of exposure of normal pigs in Canada and Costa Rica to PCV2. Recombinant DNA techniques were used to produce an antigen from ORF2 of PCV2 that was suitable for the detection of antibody in swine sera. The presence of PCV2 nucleotide sequences was detected using polymerase chain reaction (PCR) techniques. Using these tests, specific antibody and nucleotide sequences were demonstrated in sera from a cohort of pigs during a PMWS outbreak. Antibody was detected in normal, healthy hogs slaughtered in Canada (82.4% of 386) and in Costa Rica (14.6% of 322). This is the first report indicating the presence of PCV2 in Latin America. More than 50% of these sera also contained PCV2 nucleotide sequence. Although these hogs were healthy when slaughtered, they were infected with PCV2 and may have previously been ill. The widespread occurrence of PCV2 in swine suggests that this virus is adapted to replication in porcine tissue.     

Seroprevalence and risk factors of swine influenza in Spain

Swine influenza is caused by type A influenza virus. Pigs can be infected by both avian and human influenza viruses; therefore, the influenza virus infection in pigs is considered an important public health concern. The aims of present study were to asses the seroprevalence of swine influenza subtypes in Spain and explore the risk factors associated with the spread of those infections. Serum samples from 2151 pigs of 98 randomly selected farms were analyzed by an indirect ELISA for detection of antibodies against nucleoprotein A of influenza viruses and by the hemagglutination inhibition (HI) using H1N1, H1N2 and H3N2 swine influenza viruses (SIV) as antigens. Data gathered in questionnaires filled for each farm were used to explore risk factors associated with swine influenza. For that purpose, data were analyzed using the generalized estimating equations method and, in parallel by means of a logistic regression. By ELISA, 92 farms (93.9%; CI(95%): 89.1-98.7%) had at least one positive animal and, in total, 1340/2151 animals (62.3%; CI(95%): 60.2-64.3%) were seropositive. A total of 1622 animals (75.4%; CI(95%): 73.6-77.2%) were positive in at least one of the HI tests. Of the 98 farms, 91 (92.9%; CI(95%): 87.7-98.1%) had H1N1 seropositive animals; 63 (64.3%; CI(95%): 54.6-73.9%) had H1N2 seropositive pigs and 91 (92.9%; CI(95%): 87.7-98.1%) were positive to H3N2. Mixed infections were detected in 88 farms (89.8; CI(95%): 83.7-95.9%). Three risk factors were associated with seroprevalences of SIV: increased replacement rates in pregnancy units and, for fatteners, existence of open partitions between pens and uncontrolled entrance to the farm.     

An epizootic of bovine tuberculosis in Barbados, West Indies.

A 57 cow dairy herd, believed to be in excellent condition and producing well, was found to contain 30 tuberculous cattle after cervical skin testing employing bovine PPD tuberculin with the single intradermal comparative test. Testing was initiated after two cows from this herd were found at meat inspection to have tuberculosis. The reliability of bovine PPD tuberculin for testing as well as significant epidemiological, laboratory and meat inspection factors are presented.     

Seroprevalence of anti-Toxoplasma IgG in Canadian swine.

In 1990, 1443 sera randomly selected by computer generated random numbers from a bank of greater than 15,000 sera collected earlier from sows at slaughter in various geographic regions of Canada were tested for anti-Toxoplasma immunoglobin G (IgG) by the modified direct agglutination test. One hundred and thirty-six (9.4%) samples were positive for anti-Toxoplasma IgG while 36 (2.5%) of the sera gave borderline reactions. The highest prevalence of anti-Toxoplasma IgG was in swine originating in the Atlantic provinces and Ontario while the lowest was in swine from Manitoba and Saskatchewan.     

Identification of viral pathogens in aborted fetuses and stillborn piglets from cases of swine reproductive failure in Spain

The objective of the present study was to determine the presence of recognised abortifacient viruses such as porcine reproductive and respiratory virus (PRRSV), Aujeszky's disease virus (ADV), porcine parvovirus (PPV) and porcine circovirus type 2 (PCV2), in tissues from aborted fetuses and stillborn neonates in cases of late reproductive failure in swine. A total of 293 specimens (fetuses aborted in the last third of gestation and stillborn piglets) from 100 different cases of late-term abortions and premature farrowing from 15 different Spanish provinces were studied. PRRSV was detected in 9/100 cases by RT-PCR. Only 1/100 cases analysed (corresponding to a late-term aborted fetus with a negative PRRSV RT-PCR result) was positive for PCV2 by PCR. Neither ADV (monitored by viral isolation plus antigen detection) nor PPV (monitored by ELISA antigen capture test) infection was identified. The results suggest that PRRSV is one of the most important infectious agents, if not the most relevant one, associated with fetal infection leading to abortion or premature farrowing in Spain. Moreover, other viral pathogens such as ADV, PPV and PCV2 seem to have a minor impact on reproductive disease.     

Risk factors and characteristics of canine transmissible venereal tumours in Grenada, West Indies

We studied risk factors and characteristics of canine transmissible venereal tumours (TVTs) in Grenada. We abstracted data for 38 TVT cases and 114 TVT-free dogs submitted to a veterinary diagnostic laboratory between 2003 and 2006. Occurrence profiles, odds ratios (ORs), and logistic regression models for TVT were determined using a significance level of α = 0.05. TVT was found in 20 (52.6%) female and 18 (47.4%) male dogs. Of the TVT cases, 32 (84.2%) were between 1 and 7 years old, 20 (52.6%) were mixed breeds of dogs, 14 (36.8%) were Grenadian pothounds, while 4 (10.6%) were pure-bred dogs. Characteristic TVT lesions were genital growths [OR = 96.7; 95% CI (27,461), P < 0.001], genital bleeding [OR = 12.7; 95% CI (4.6, 39.2), P < 0.001] and secondary inflammation of TVT lesion [OR = 4.3; 95% CI (2, 10), P < 0.001]. Extragenital TVT lesions were observed in 23% (9/38) of dogs. An increased risk for TVT was associated with age as adult (1–7 years) dogs [OR = 12; 95% CI (1.6, 94), P < 0.001] and status as a Grenadian pothound [OR = 8.6; 95% CI (3, 25), P < 0.001]. Clinicians should educate dog owners about increased risk of TVT for Grenadian pothounds and consider TVT as a possibility for some extragenital tumours.     

Integrating banana and ruminant production in the French West Indies

Using a mechanistic model, we compared five alternative farming systems with the purpose of transforming monoculture (MON) banana farms into mixed farming systems (MFS) with ruminants feeding banana by-products (leaves, pseudostems and nonmarketable fruits) and forage from the fallow land. The paper presents the main structure of the model (land surface changes, available biomass for animals, stocking rates, productive or reproductive indicators), and impact assessment (change in farm productivity) is discussed. Five MFS with typical local ruminant production systems were used to compare MON to the strategies using forage from fallow and/or integrating Creole cattle (CC), Creole goats (CG) or Martinik sheep (MS) into banana farming. One hectare MON shifted into an MFS allows a stocking rate of 1,184, 285, and 418 kg of live weight per hectare for CC, CG and MS, respectively. Banana by-products seem to be better valorized by the CC scenario. However, parameters such as length of the cycle, local prices for cattle, goat and sheep meat, work time and farmer's skills in ruminant management may have been taken into account by the farmer when choosing the ruminant species to rear.     

Non-experimental validation of ethnoveterinary plants and indigenous knowledge used for backyard pigs and chickens in Trinidad and Tobago

This paper presents the findings of an exploratory study on ethnoveterinary medicines used for backyard pigs and backyard chickens in Trinidad and Tobago. Research data was collected from 1995 to September 2000. Six plants are used for backyard pigs. Crushed leaves of immortelle (Erythrina pallida, E. micropteryx) are used to remove dead piglets from the uterus. Leaf decoctions of bois canôt (Cecropia peltata) and bamboo (Bambusa vulgaris) are used for labour pains or leaves are fed as a postpartum cleanser. Boiled green papaya fruit (Carica papaya) is fed to pigs to induce milk let-down. The leaves and flowers of male papaya plants (Carica papaya) are fed to de-worm pigs. Sour orange juice (Citrus aurantium) is given to pigs to produce lean meat, and coffee grounds are used for scours. Eyebright and plantain leaves (Plantago major) are used for eye injuries of backyard chickens. Worm grass (Chenopodium ambrosioides) and cotton bush (Gossypium species) are used as anthelmintics. Aloe gel (Aloe vera) is used for internal injuries and the yellow sap from the cut Aloe vera leaf or the juice of Citrus limonia is used to purge the birds. A literature review revealed few toxicity concerns and the potential usefulness of the plants.     

Seroprevalence and molecular characterization of West Nile Virus in Egypt

West Nile Virus (WNV) is a flavivirus, mosquito-borne infection and have public health importance worldwide. WNV infection have highly significant impact on animal and human health. The virus has been detected serologically in Egypt among equids. Therefore, the aim of the present study to investigate the serological situation of WNV among horse in north of Egypt and identification of WNV in vector. The serological survey was conducted on 500 serum samples that collected from horses from four governorates at north of Egypt. The infection rate was non-significant differed between four localities and the highest rate was reported in Qalyubia governorate (25.5 %) in comparison with other areas. Moreover, the WNV RNA was detected in mosquitoes and the obtained WNV sequence showed high similarity with Eg101 strain and characterized as lineage 1. The obtained findings confirm the circulation of WNV in mosquitoes and animals in Egypt.