当心猪的巨细胞病

<正>巨细胞病毒(CMV)亦称细胞包涵体病毒,由于感染的细胞肿大,并具有巨大的核内包涵体,故称为巨细胞病毒。巨细胞病毒病是人畜共患病,但人畜之间互不传染。在猪场,全世界98%以上的猪群受到过感染     

四川省猪巨细胞病毒病感染调查及分析

为了掌握四川省猪巨细胞病毒病感染情况,为今后的猪巨细胞病毒病防治打下基础,进行了猪巨细胞病毒病感染情况的调查和分析工作。实验采用四川农业大学动物生物技术中心建立的PCMV套式PCR检测方法,对采自四川省11个地市的204份血清和组织样品进行了检测,感染调查结果显示,目前四川地区的规模化猪场普遍存在猪巨细胞病毒感染情况,抗原平均阳性率高达81.9%。该病毒在猪各器官内均有分布,在不同类别的猪群中,仔猪、保育猪和种母猪的抗原阳性率很高,都达到80%以上,种母猪平时不发病,但受感染母猪会产出木乃伊胎和弱仔,会严重影响猪种群质量和猪场经济效益。     

猪巨细胞病毒病的诊断与防治

<正>猪巨细胞病毒病是由猪巨细胞病毒引起仔猪的一种常见传染病[1],该病毒遍布全球,北美、欧洲和日本的90%以上的猪群曾受到感染[2]。我国于1991年首次报道,广西2008年也报道有猪巨细胞病毒病发生[3,4]。2014年广西桂林市一猪场发生了一起猪巨细胞病毒病,现将其诊治情况报告如下。1发病情况该场自繁自养,存栏母猪约200头。2014年5月,哺乳仔猪出现精神沉郁,呼吸困难,体重很快减     

猪巨细胞病毒病的综合防控措施

猪巨细胞病毒病是由猪巨细胞病毒引起的一种条件性传染病。猪巨细胞病毒病在猪群中普遍存在,常呈潜伏性感染,临床上易被忽视或被误认为是其他疾病所表现的症状,这可能错过最佳治疗时机,造成巨大的经济损失。因此,本文从猪巨细胞病毒病的流行病学、临床症状、病理变化、诊断方法、治疗及预防措施等方面进行综述,为养殖户对该疾病的治疗与预防提供参考。     

猪巨细胞病毒致病机理及主要蛋白研究进展

巨细胞病毒是一种可感染人类和猪的病原体。目前巨细胞病毒病在世界各地均有发生,我国也有多个地区存在该病的感染情况。该病在成年猪多呈隐性感染,但对仔猪可引起致命的全身感染,妊娠猪可经胎盘感染胎儿,且目前尚无特效治疗药物和方法。本文主要对其致病机理及主要蛋白研究进展进行了综述,以期为猪巨细胞病毒病的深入研究提供参考。     

猪巨细胞病毒病的流行特点及其诊断方法

猪巨细胞病毒病是由猪巨细胞病毒(PCMV)引起仔猪的一种条件性传染病,主要是侵害猪的呼吸系统,临床上以鼻炎为特征,在感染的鼻甲骨黏膜黏液腺中巨细胞可见到大量嗜碱性核内包涵体,又称包涵体鼻炎.PCMV是继伪狂犬病的病毒之后发现的第二个猪疱疹病毒,属于疱疹病毒科、β疱疹病毒亚科、巨细胞病毒属的成员,它可感染人、鼠、牛、马、猫、猪等多种哺乳动物.由于该病常呈隐形感染,在生产中不易引起重视,给养猪业造成很大的疫病隐患.     

目前猪常见混合感染疾病防制

<正>目前生猪的疾病大多均以病原的多重感染或混合感染为主要流行形式,80%以上的发病猪均是由2种或2种以上病原混合感染,且70%以上的发病猪以病毒病为主,在生猪发生的病毒病中又以猪瘟、猪繁殖与呼吸综合征(蓝耳病)、圆环病毒病为主;75%以上的病猪有细菌性疾病并发或继发,且在生猪并发或继发的细菌性疾病中又以猪链球菌病、气喘病、附红细胞体病、弓     

猪巨细胞病毒病

猪巨细胞病毒(Porcine Cytomegalovirus,PC-MV)是由疱疹病毒科β疱疹病毒亚科巨细胞病毒属的一种[1].该病毒遍布全球[2],猪感染该病也是普遍存在,在北美、欧洲和日本,90％以上的猪群曾受到感染.对成年猪只通常只呈现隐性感染,而对3周龄以下仔猪常常诱发致命性的全身感染[3].     

规模化猪场繁殖障碍性疾病的血清学调查

此试验用酶联免疫吸附试验(ELISA)方法对规模化猪场的1498份猪血清进行了猪繁殖与呼吸综合征(PRRS)、猪伪狂犬病(PR)、猪细小病毒病(PP)、猪日本乙型脑炎(JE)、猪瘟(HC)以及猪圆环病毒2型(PCV2)感染的抗体检测。检测结果表明,猪瘟免疫抗体的阳性率为69.0%(156/226);猪细小病毒病、猪日本乙型脑炎和猪伪狂犬病免疫抗体的阳性率分别为79.9%(175/219)、87.2%(191/219)和74.8%(217/290);猪繁殖与呼吸综合征免疫抗体的阳性率为58.8%(67/114),未免疫抗体的阳性率达61.5%(150/244);猪圆环病毒2型感染未免疫抗体的阳性率为66.7%(98/147)。结果表明,引起繁殖障碍的疾病中,猪细小病毒病、猪日本乙型脑炎和猪伪狂犬病的免疫效果较好;而猪繁殖与呼吸综合征的免疫效果较差,并与猪圆环病毒病困扰某些猪场。根据检测结果,提出了相应的防制措施。     

猪巨细胞病毒病研究进展

<正>猪巨细胞病毒病是由于猪感染猪巨细胞病毒(Porcinecytomegalovirus,PCMV)而引起的仔猪一种常见传染病。患猪特征性临诊症状为食欲废绝,母猪繁殖障碍,表现为流产、死产、木乃伊胎、产弱仔等;仔猪有明显的眼炎、鼻炎和肺炎症状,生长发育不良,增重差。由于本病的特征性鼻炎症状,并在感染的猪鼻甲骨粘膜粘液腺中可见到大量嗜碱性核内包涵体,因而又将PCMV引起的这种疾病称为包涵体鼻炎。PCMV分布相当广泛,现有报道显示,常规条件下饲养的大多数猪群均存在PCMV感染,PCMV抗体阳性率都很高,但大多数为亚临床型,或与其他病原混感发病。     

Comparative efficacy of ten commercial Campylobacter fetus vaccines in the pregnant guinea pig: challenge with Campylobacter fetus serotype A.

Efficacy of ten commercial Campylobacter fetus vaccines was tested in pregnant guinea pigs and compared with that of an experimental vaccine prepared from the challenge-exposure strain. If the first lot of vaccine failed to protect 50% of the guinea pigs, one or two additional lots of that vaccine were purchased and retested. Three vaccines for cattle, evaluated, as the most effective of those tested, protected 62%, 72%, and 89% of the guinea pigs from abortion; the experimental vaccine protected 98%. The two vaccines for sheep protected 50% and 61% of the guinea pigs from abortion. With the other five vaccines produced for immunizing cattle, protection was from 0% to 36%, with the exception of one lot of a vaccine that protected 74%. Blood infection was found at necropsy in only 6% of the guinea pigs given vaccines that protected 50% or more from abortion, but was found in 66% of those given vaccines that protected less than 50%. Similarly, tissue infection was found at necropsy in only 18% of the guinea pigs given vaccines that protected more than 50%, but was found in 91% of those given vaccines that protected less than 50% from abortion. Oil-emulsion adjuvants appeared to enhance protection from abortion and infection. Nodules persisted at the injection site in most of the guinea pigs immunized with vaccines containing oil-emulsion adjuvants, but rarely persisted in guinea pigs given aqueous-phase adjuvant vaccines. Comparison of efficacy of the vaccines in guinea pigs with efficacy in sheep and cattle remains to be made.     

Effects of Duroc, Meishan, Fengjing, and Minzhu boars on productivity of mates and growth of first-cross progeny.

Meishan, Fengjing, Minzhu, and Duroc boars were mated by AI to crossbred gilts to compare the sire breeds for effects on productivity of their mates and performance of their progeny. Gilts were derived from a four-way cross of Chester White, Landrace, Large White, and Yorkshire. At weaning, litters sired by Meishan boars averaged 1.69 and 1.32 more pigs than those sired by Duroc and Minzhu boars, respectively (P less than .05). Pigs sired by Meishan and Fengjing boars averaged 1.2 to 1.8 more nipples than pigs sired by Duroc and Minzhu boars (P less than .05). Minzhu-sired pigs had a lower (P less than .05) survival rate to 14 and 28 d of age than did those sired by Meishan, Fengjing, and Duroc. Fengjing-sired pigs were heavier than Minzhu-sired pigs at birth and heavier than Minzhu- and Duroc-sired pigs at 14, 28, and 56 d of age (P less than .05). At 70 d of age, Meishan-sired pigs were heaviest, followed in order by Fengjing-, Duroc-, and Minzhu-sired pigs. At 98 d of age, Meishan-sired pigs were significantly heavier than all other breed groups and Duroc-sired pigs were significantly heavier than Minzhu-sired pigs. At 126 and 154 d of age, Duroc-sired pigs were heaviest, followed in order by Meishan-, Fengjing-, and Minzhu-sired pigs; all differences were significant. Average backfat thickness of gilts at 99.7 kg was least for Duroc-sired gilts and highest for Meishan-sired gilts. Sire breed groups did not differ significantly in feed efficiency from 70 to 98 d of age. Duroc-sired pigs were the most efficient (P less than .05) from 98 to 126 and 126 to 154 d of age. Results indicate that use of these Chinese breeds in crossbreeding programs will decrease performance traits. This decrease would have to be offset by increases in reproductive efficiency of Chinese sows, use of repartitioning agents, or other management techniques if Chinese pigs are to improve overall production efficiency of a crossbreeding program.     

Diagnoses and treatments in health-classified fattening herds rearing pigs all in-all out

This study describes diseases encountered, medications used and veterinary involvement in all in--all out finishing herds belonging to one pork production system. The finishing herds had a particular management and housing regime. The pigs originated from health classified farrowing units. Information on 207,442 pigs was collected from 595 log books. Altogether 91% of the pigs received no treatments. Four percent of the batches of pigs were given antimicrobial mass medications. The local veterinarian visited the herds on average 2.6 times during the finishing period and made the diagnoses in more than half of the cases. At least one pig was affected with arthritis or tail biting in more than half of the batches, whereas locomotory diseases were recorded in one third of the batches. All other diagnoses were encountered in 1%-13% of the batches. Only a few pigs were treated individually in the affected groups. Antimicrobial drugs were given to 8% and other medicines to 0.7% of the pigs. The diagnosis was missing at least for one pig in 29% of the batches and the information about the medicine use in 8% of the treatments was missing. The study shows that it is possible to rear finishing pigs with only a small proportion of the animals needing treatments. The need of mass medications was low, because infectious diseases affecting the whole herd were uncommon. The recommendations for antimicrobial use given by the authorities had been followed quite well. The farmers and the veterinarians should be educated in order to realise the importance of proper record keeping.     

Growth, carcass characteristics, and lipid composition of adipose tissue and muscle of pigs fed canola

Sixty-one finishing pigs (53.4 kg) were fed a control diet (containing soybean meal) or diets containing 20% intact canola (IC) or 20% ground canola (GC) for 8 wk. Diets were not isocaloric. Daily gain and feed efficiency were not affected by dietary treatment, but pigs fed GC ate less than pigs fed either IC or the control diet. Carcass measurements, obtained on 43 of the pigs, were not affected by diet. For 27 pigs, fatty acid composition of perirenal adipose tissue (PRF), subcutaneous adipose tissue (SCF), and longissimus muscle (LDM) was analyzed. Nine pigs (three per treatment) were randomly selected for fatty acid composition analysis of intramuscular adipose tissue (IMF) and for cholesterol analysis of several tissues. Pigs fed canola had greater (P less than .05) proportions of mono- and polyunsaturated fatty acids and less (P less than .05) saturated fatty acids in PRF and SCF. The differences were more pronounced for PRF than for SCF. In the LDM, pigs fed canola tended to have elevated levels of unsaturated fatty acids at the expense of the saturated fatty acids, but this effect was significant for linolenic acid only. The fatty acid composition of IMF was not affected by diet (P greater than .05). Diet did not alter the cholesterol content of the tissues, but cholesterol in IMF was higher (P less than .05) than in PRF, SCF, and LDM. In conclusion, 20% IC or GC did not alter growth performance or carcass characteristics of pigs. Feeding of canola increased the degree of unsaturation of PRF and SCF, but it had less effect on IMF and LDM.     

Effects of temperature on the performance of finishing swine: I. Effects of a hot, diurnal temperature on average daily gain, feed intake, and feed efficiency

Ninety-six crossbred barrows and gilts weighing 90 +/- .67 kg were used during a 21-d study to determine the effects of a hot, diurnal temperature (H; 22.5 to 35 degrees C) compared with a constant, thermoneutral temperature (TN; 20 degrees C) and the effects of sex (barrows vs gilts) on performance. A secondary objective included the determination of weight loss as a result of a 24-h fast immediately after the 21-d feeding study of commingled vs not commingled hogs of both environmental treatments (TN and H). Pigs housed in the hot, diurnal temperature gained 16.3% more slowly (P less than .001;.77 vs. .92 kg/d) than those in the constant, thermoneutral environment. Feed intake (FI) for the H pigs was 10.9% less (P less than .001; 3.01 vs 3.38 kg/d) than that for the TN pigs. The H pigs gained 17.6 g/d less and consumed 43.5 g/d less feed for every C degrees above 20 degrees C; however, no differences were observed for feed efficiency (F/G; 3.86 vs 4.19 kg for the TN and H pigs, respectively). Average daily gain and feed/gain (F/G) were not affected by sex. Likewise, no significant interactions of temperature x sex were observed for ADG, FI, or F/G. Weight loss (shrinkage) during the 24-h fast was not affected by commingling; however, the H pigs lost 17.5% more weight (P less than .05) than the TN pigs (3.82 vs 3.25%, respectively).     

Isolation of circovirus from lesions of pigs with postweaning multisystemic wasting syndrome.

Postweaning multisystemic wasting syndrome (PMWS), an apparently new disease, has been recognized in swine herds in western Canada. Young pigs with this disease have progressive weight loss, tachypnea, dyspnea, and jaundice, accompanied by interstitial pneumonia, lymphadenopathy, hepatitis, and nephritis. We examined more than 400 pigs from more than 70 herds in Alberta, Saskatchewan, and Manitoba with cases of PMWS. A small virus was isolated from a range of tissues from 8 of 8 affected pigs examined. The agent was identified as a circovirus-like virus using electron microscopy, immunohistochemical staining with porcine and rabbit immune serum, and in situ hybridization. Immunohistochemical examination of tissues from more than 100 affected pigs has revealed widespread viral antigen, often contained in circovirus-like inclusion bodies, in lesions from numerous organs. Although Koch's postulates remain to be fulfilled, these results demonstrate a high degree of association between the presence of the circovirus-like virus and PMWS in affected swine.     

Granulomatous lesions in lymph nodes of slaughter pigs bacteriologically negative for Mycobacterium avium subsp. avium and positive for Rhodococcus equi

The prevalence of granulomatous lesions in lymph nodes of pigs was studied. From January till August 2004 in two slaughterhouses in The Netherlands 2,116,536 pigs were examined for the presence of granulomatous lesions in the sub-maxillary lymph nodes. In 15,900 (0.75%) of these pigs, lesions could be detected. Nine farms with the highest incidence of lesions were selected for a more detailed pathological and bacteriological examination. On these farms, the prevalence of lesions in sub-maxillary lymph nodes ranged from 2.3 to 5.7% with a mean of 3.0%. From 1276 pigs that were sampled, 98 (7.7%) displayed granulomatous lesions in the sub-maxillary lymph nodes and one (0.1%) pig showed lesions in its mesenteric lymph node. Mycobacterium avium subsp. avium (MAA) could not be isolated from the lymph nodes of the 99 pigs with lesions and from a selection of lymph nodes (n = 61) of pigs without lesions. Rhodococcus equi was isolated from 44 out of 98 (44.9%) of the sub-maxillary lymph nodes with granulomatous lesions and from two mesenteric lymph nodes without lesions. A comparison of former studies and the current results indicate that the prevalence of MAA infections in slaughter pigs has strongly decreased over the last decade, whereas R. equi is highly prevalent. The high incidence of granulomatous lesions associated with the bacteriological presence of R. equi could be considered as a serious cause of misdiagnosis of MAA infections in cases where meat inspection is carried out by inspection for granulomatous changes of lymph nodes only.     

Survey of internal parasites in Western Australian pig herds. 1. Prevalence

Between September 1982 and March 1984, 101 Western Australian piggeries with 15 or more sows were surveyed to determine the prevalence of internal parasites and examine the relationship between parasitism and management practices. Faecal samples were collected from 20 pigs in 4 age groups in randomly selected piggeries, and examined for the presence of eggs of helminth parasites and protozoan cysts. Evidence of nematode parasites was found in 79% of piggeries. Sows were more commonly affected than other classes of pigs with worm eggs being found in 68% of herds. Oesophagostomum spp was the most prevalent worm species, being found in pigs from 65% of piggeries and in sows in 60% of herds. Ascaris suum was the most common species of worm found in growing pigs. There was no evidence of infection with either Metastrongylus spp or Strongyloides spp in any of the herds sampled. Oocysts of coccidia were found in pigs from 56% of piggeries and Balantidium coli cysts were detected in pigs from 42% of piggeries sampled.     

Porcine coccidia in Papua New Guinea

Faecal samples from 232 domestic pigs raised on concrete, 98 free-ranging village pigs, and five wild boar showed 46.6 (108/232), 54 (53/98) and 80% (4/5) prevalence of coccidian oocysts, respectively. Eight species of Eimeria, and Isospora suis, were recovered. In their descending order of predominance in the pigs raised on concrete, the species of coccidia were E. debliecki (26.7%), E. scabra (22.4%), E. neodebliecki (19.8%), E. porci (15.5%), E. suis (11.6%), E. polita (8.6%), E. perminuta (7%), E. spinosa (5.6%) and I. suis (3.9%). The first five species listed above predominated in the village pigs as well. E. polita, E. spinosa and I. suis were not found in the wild boar. I. suis oocysts prevailed in 8.3% of the 36 sows on concrete, and in 11.1% (3/27) of those which were positive for coccidia. Isosporoid oocysts were absent in the village sows. Of the 125 less than 24-day-old piglets, 29.6% were diarrhoeic, and of these, 43.2% were positive for coccidia. Four of the 16 (25%) coccidia-positive, diarrhoeic piglets, and four of the 37 (10.8%) coccidia-positive non-diarrhoeic piglets shed I. suis oocysts, an observation which seems to weaken the present contention that I. suis is the primary causative agent of neonatal porcine coccidiosis. The highest mean number of oocysts per gram faeces (23,550) was recorded from the diarrhoeic farm piglets on concrete, and the lowest of 6,100 from the gestating farm sows. Mean opg data revealed very little significant quantitative variation between the corresponding age groups of the free-ranging village pigs and the commercially-farmed ones. One of the most interesting findings in the study was that the sows were more frequently infected than all other age groups.     

Biological, chemical and pathohistologic study of the skin in papular dermatitis in fattened pigs

We examined the skin samples from 23 fattened pigs with papular dermatitis (PD) and from 17 pigs showing no skin lesions; the live weight of the pigs was from 95 to 105 kg and the pigs came from a large fattening house D that is located in the region where the mines are frequent (lignite extraction). It was only in 26% of pigs with PD where the common ectoparasites Haematopinus suis and Sarcoptes scabiei var. suis were found out. The skin lesions were not fluorescent in the light of Wood's lamp. The fungi Aspergillus flavus, A. fumigatus, A. tereus, Chrysosporium, Mucor sp., Scopulariopsis sp. were sporadically isolated from the skin lesions in 39% of pigs with PD. In 65% of pigs with PD Staphylococcus aureus was isolated from the skin lesions, which was not found in pigs without dermal lesions. Staphylococcus epidermidis was isolated in 87% of pigs with PD and 58% of pigs without any skin changes. The skin lesions were virus-free. Increased concentrations of cadmium and mercury were observed in the skin of pigs with PD and in control pigs. The concentration of aflatoxin B1 in the skin of the two groups of pigs did not exceed the level of 5 micrograms X kg-1, in PD pigs it was, however, twice higher than in the clinically healthy pigs. The residues of chlorinated hydrocarbons in the subcutaneous fat were not higher than the certified hygienic levels. Both epidermis and corium are affected by inflammatory lesions. At the beginning, neutrophil infiltration with necrotization of epithelial cells prevails. It is followed by capillary proliferation with angioblast and fibroblast multiplication and straggled lymphoid infiltration. It is necessary to distinguish by differential diagnostics: swine pox, parakeratosis of swine, lesions of impetigo contagiosa suum, pustular dermatitis and scab of swine, and from rarely occurring skin diseases of swine hypotrichosis cystica suis and demodicosis of swine. No conclusions can be drawn explicitly on the etiology and pathogenesis of papular dermatitis in fattened pigs. We must study the potential interactions of negative environmental factors with regulating homeostatic and adaptation mechanisms in fattened pigs.