A Comparison of the Susceptibility of Growing Mukota and Large White Pigs to Infection with Ascaris suum

The influence of A. suum infection on the haematology, liver-related serum enzymes, blood urea and live weight gain in Mukota and Large White (LW) weaner pigs was compared. Six pigs of each genotype were infected with a single dose of 4000 A. suum eggs per pig and another six were not. The pigs were kept for 100 days. Blood was collected daily for the first 7 days and also after 100 days. In the infected pigs, there was an increase (p<0.05) in alanine aminotransferase (ALT) activity in the LW but not in the Mukota pigs. Although the alkaline phosphatase (ALP) activity rose (p<0.05) in both infected and non-infected LW pigs from day 1 to day 3, the activity in the non-infected LW pigs then decreased, while that of the infected LW pigs remained elevated. The infected LW pigs had higher (p<0.05) levels of ALT, ALP and aspartate aminotransferase than their non-infected counterparts. Non-infected LW pigs tended to have higher (p<0.05) haematological parameters, daily weight gain and urea concentrations than infected LW pigs, but these differences were not significant. These preliminary findings suggest that more A. suum larvae reached the livers in the LW than in the Mukota pigs and that the latter may be more resistant to A. suum infection.     

Anoplocephala perfoliata in Horses in Sweden: Prevalence,Infection Levels and Intestinal Lesions

Distal ileum, caecum and proximal colon of 470 horses were examined for helminths during 1 year at an abattoir in central Sweden. The infection levels of the horse tapeworm Anoplocephala perfoliata, their stage of development, site of attachment and gross pathological lesions caused by the worm were recorded. Faecal samples from 395 of the horses were examined specifically for tapeworm segments and eggs in order to correlate these findings with the numbers in the alimentary canal. In total 65% of the horses were infected with A. perfoliata and the mean intensity of infection was 79 worms per infected horse with a maximum of 912. The level of infection was significantly higher in (1) 3rd and 4th than in 1st and 2nd quarter of the year; (2) older horses than in yearlings; (3) females than in males and geldings; (4) thoroughbreed and cold-blooded horses than in Swedish standardbreeds and ponies. The level of infection was unaffected by the usage of anthelminthics against nematodes. Of the horses examined 51% had 1-100 worms whereas 14% were infected with more than 100 worms. Of the tapeworm positive horses 72% had mixed infections with both adult and juvenile worms, 20% solely juveniles, and 8% solely adults. The severity of intestinal lesions exacerbated by increasing numbers of A. perfoliata. About 11% of the intestines examined had severe lesions, but there was no history of acute abdominal distress in any of the horses included in this study. Although the number of detectable eggs was significantly higher for horses heavily infected with A. perfoliata, the egg recovery among infected horses was only 35%. An additional field survey comprising 218 horses on 88 premises in central and southern parts of Sweden showed that the prevalence of A. perfoliata egg positive horses was the same as found on faecal examination during the abattoir survey.     

Effects of Salmonellosis on subsequent infections with Ascris suum in swine

Weanling pigs were exposed to Salmonella cholerae-suis var. kunzendorf and sixteen days later were inoculated with infective Ascaris suum eggs. Necropsy at seventeen days post-Ascaris-infection revealed fewer lesions of hepatic fibrosis and a lesser degree of tissue eosinophilia in the hepatic interstitium in pigs receiving inoculations of Salmonella and Ascaris compared to those receiving Ascaris inoculation only. The numbers of juvenile nematodes recovered from the small intestines of both groups were variable. The comparatively less-intensive hepatic lesions may have been caused by reduction of the number of penetrating larvae at the intestinal level. Alternatively, the decreased tissue eosinophilia and fibrosis of the liver may be due to the previous stress of the Salmonella infection.     

Pneumonia in Saskatchewan Swine: Abattoir Incidence of Intrathoracic Lesions in Pigs from a Herd Infected with Haemophilus pleuropneumoniae and from Other Herds

A 1978-79 survey of the incidence of thoracic cavity lesions at slaughter had shown that the overall incidence of pleurisy in Saskatchewan swine was low (2%). Therefore, in the summer of 1979 a comparison was made between the incidence of pleurisy in a herd of pigs chronically affected with Haemophilus pleuropneumoniae pneumonia and in animals from other herds slaughtered at the same time. The incidence of pleurisy in control pigs (3.6%) was slightly higher than in the large scale survey but in the pigs from the Haemophilus infected herd it was almost four times as great (13.3%). In the same herd the survivors of a batch of pigs which had been decimated by more severe disease showed an incidence of 32% pleurisy. The economic implications of these findings are detailed and discussed.     

Sequential development of esophagogastric ulcers induced in swine by infections with Ascaris suum goeze, 1782

Twenty-five experimental and five control hysterectomy derived pigs were raised colostrum free under specific pathogen-free conditions. The experimental pigs were first inoculated with A. suum eggs at 8 weeks of age, and a second dose of infective eggs was given 15 days later. They were necropsied from 4 to 10 days post second infection.The ulcers found in the stomach of these pigs were confined to the esophagogastric area. A sequence of epithelial changes, erosions, and ulceration was seen in the stratified squamous epithelium. Edema and hemorrhage were noted in the lamina propria and submucosa. Vascular changes in the area were characterized by thickening of the wall and presence of thrombi in arteries as well as cellular degeneration and vacuolization of the media and intima of the veins.Changes in the muscularis were characterized by edema and degeneration of the muscle cells, which later were replaced by fibroblasts and heavy infiltration by eosinophils.Three of the control pigs received one dose of A. suum eggs, and were killed one on each of the 8th, 9th, and 10th days post infection. The remaining two pigs received no infective material and were killed when they were 11 weeks of age. Neither the uninoculated pigs nor the once-inoculated animals developed ulcerations in their stomachs.The possible mechanisms by which esophagogastric lesions are produced following A. suum larval migrations are discussed.     

Application of a real-time PCR assay for the detection of Ascaris suum DNA in the liver of experimentally infected chickens

This study aimed to evaluate the sampling method for the detection of Ascaris suum larval DNA in chicken livers using real-time PCR. Chickens were inoculated with A. suum eggs of a single dose (Group A) or repeatedly low doses (Group B). White spots (WSs) were continuously observed on liver from day 3 after the last infection in Group B and day 14 in Group A. In Group A, larval DNA was detected in WS lesions (78.6%) at a significantly higher rate than in the remaining tissue samples (31.3%). In conclusion, applying WS lesions to the assay improved the detection rate of A. suum DNA in chicken livers, especially in the case of a single infection.     

An Abattoir Survey of the Incidence of Pneumonia in Saskatchewan Swine and an Investigation of the Microbiology of Affected Lungs

The lungs of 15 409 pigs, mostly from Saskatchewan, slaughtered at an abattoir were examined over a one year period. The incidence of lesions was 36.7% for “enzootic” pneumonia and 2.1% for pleurisy unassociated with pneumonia. Seasonal variations were recorded and compared with the results of similar surveys carried out in Australia, Belgium and England. Mycoplasmological examination of lungs from 347 animals was consistently negative for Mycoplasma hyopneumoniae. Pasteurella multocida was the commonest bacterial isolate, a result which agrees with those of other workers.     

Survey of Gastric Lesions and Blood Pepsinogen Levels in Pigs in Burkina Faso

The purpose of the study was to investigate the prevalence of gastric lesions and to provide diagnostic values for serum pepsinogen in non-infected pigs and in pigs with gastric disease. In an abattoir survey, the pepsinogen concentrations were measured in the serum from 62 non-infected pigs, 33 pigs with gastric lesions and 17 pigs infected with Hyostrongylus rubidus, using a specific radioimmunoassay (RIA). The mean (±SE) pepsinogen concentrations in the serum of non-infected pigs, in pigs with gastric ulcers, and in pigs with a heavy H. rubidus infection were 630.8±39.2 ng/ml, 1084.5±166.2 ng/ml and 1095.2±102.3 ng/ml, respectively (p<0.05). Because of the higher concentrations of pepsinogen in the blood of pigs with gastric ulcers or parasitic infections, it is suggested that the measurement of serum pepsinogen by RIA may be an effective biochemical approach to the diagnosis of chronic gastric disorders in pigs.     

Swine brucellosis in Indonesia

Summary

Brucella suis biotype 1 was isolated from 13.1% of the pigs slaughtered in Kapuk Jakarta, West Java and from 15.09% of the pigs slaughtered in Surabaya, East Java. The prevalence of B. suis by means of the Rose Bengal Plate Test, was 22.3% for West Java and 14.9% for East Java. The Rose Bengal Plate Test detected more B. suis infected animals (73% of the infected animals) than did the Complement Fixation Test (41%) and the Serum Agglutination Test (54.5%).

The high infection rate is a potential health danger for the abattoir workers.     

The prevalence of macroscopic sarcocysts in New Zealand cattle at slaughter

A survey carried out to determine the prevalence of visible Sarcocystis spp. infection in 100 slaughtered cattle in a South Island abattoir revealed 64% infected. Although all ages, genders, breeds and export grades were infected, only host age had a statistically significant effect on the infection rate.

Infections were most common in the rectus abdominis and the psoas muscles (47% and 41% respectively). Most infections were light, with less than ten macrocysts seen, though infections of more than 50 macrocysts occurred.

The average macrocyst length was 4.1±0.10 mm (SE) (n = 233), the average cyst wall thickness 5.3 ±0,12 μm (SE) (n = 45).

It is thought that the actual prevalence of infection is higher than that recorded and reasons for this are discussed.     

Some observations on the liver copper status of pigs in the northern part of New Zealand

The copper content of the livers from 347 pigs was analysed. Two hundred and three of these samples were from animals varying in age from full term foetus to five years, which were submitted to the laboratory (laboratory cases) for a variety of diagnostic tests. The remaining 144 liver samples were obtained from pigs slaughtered at an abattoir (abattoir survey) at 75-S kg liveweight (approximately 20–30 weeks old).

Liver copper levels of 12 mg/kg D.M. (Dry Matter) or less, a level consistent with copper deficiency, were found in 6.9% of the laboratory cases and in 9.0% of the abattoir survey pigs. Liver levels less than 20 mg/kg suggesting insufficient dietary copper to produce a growth-promoting effect, were found in 21.6% of the former and 36.1% of the latter pigs.

A significantly greater frequency of illthrift and anaemia was found in the laboratory cases in which liver copper levels were less than 20 mg/kg compared with animals with higher levels. Liver copper levels less than 20 mg/kg were also more common in pigs derived from dairy farms or fed garbage than in animals from pig farms or fed on meal.

All of 26 samples of commercial pig meal analysed contained sufficient copper to satisfy the daily essential copper requirements of pigs (greater than 5–6 mg/kg) but 14 of these (53.8%) contained less than 125 mg/kg levels of copper and were unlikely to produce a growth-promoting effect.     

Association of increased rate of condemnation of broiler carcasses due to hepatic abnormalities with immunosuppressive diseases in the broiler chicken industry in Saskatchewan

The objective of this study was to identify the causative agents of hepatitis observed in broiler chickens at processing. Livers of chickens from 16 broiler farms in Saskatchewan with gross lesions of hepatitis were collected at processing. In addition to routine bacterial isolation and histopathological examination, serologic studies for infectious bursal disease virus (IBDV) and Chicken anaemia virus (CAV), calculation of the ratio of the weight of the bursa of Fabricius (BF) to body weight (BBW), and histopathological examination of the BF were done. Of the 264 livers with gross lesions, 83% had multifocal to coalescing necrotizing hepatitis, 16% had perihepatitis, and 1% had hemorrhages. No definitive causative microorganisms were isolated from the hepatic lesions; however, no significant bacterial isolations were made. Bursal atrophy, low BBW ratio, and high titer of antibody against IBDV each correlated with the rate of total condemnations (P = 0.0188, P = 0.0001, and P = 0.0073, respectively). Nucleotide sequencing of IBDV isolated from the BF identified the variant strains Delaware-E and 586. Condemnation because of hepatic lesions was correlated with titer of antibody against IBDV and BBW (P = 0.016 and P = 0.027). The results of this study demonstrate that hepatic lesions in Saskatchewan chickens are not currently caused by a primary bacterial pathogen but are associated with indicators of immunosuppression that is likely due to variant IBDV.     

Polyerositis and Arthritis Due to Escherichia coli in Gnotobiotic Pigs

Forty gnotobiotic pigs from six litters were exposed orally to Escherichia coli 083:K·:NM at 69 to 148 hours of age, while 17 pigs from the same litters served as unexposed controls. Clinical signs of infection included fever, anorexia, diarrhea, lameness, and reluctance to move.

Eighty-four percent of the exposed pigs in four litters died, while only 13% in two litters died. Gross and microscopic lesions included serofibrinous to fibrinopurulent polyserositis in 96% of the exposed pigs in four litters and 33% of the exposed pigs in two litters. A few pigs had gross and/or microscopic lesions of arthritis. Escherichia coli was routinely isolated from the serous and synovial cavities of infected pigs.

Anti-hog cholera serum administered orally as a colostrum substitute gave partial protection against E. coli infection.

     

Detection of Actinobacillus pleuropneumoniae Infection in Pigs

It is difficult to control the spread of porcine haemophilus pleuropneumonia caused by Actinobacillus pleuropneumoniae because there is no sensitive and specific way to accurately determine whether or not a pig herd is infected. This paper reports bacteriological and serological techniques used to detect A. pleuropneumoniae infection in pigs from a herd with endemic disease.

The bacteria were isolated from the anterior nasal mucosa of grower pigs, but not from younger or older pigs. Bacteriological culture of several tissues from the respiratory tract showed that nine of ten young finishing pigs were infected, but culture of lung tissue from slaughtered hogs detected infection in only 39 of 288 (13.5%). Both cooler storage temperature and use of selective medium prolonged the time that lung tissue could be stored and the organism still recovered. An enzyme-linked immunosorbent assay detected serotype-specific antibodies in serum of infected pigs.

     

The response of pigs experimentally infected with trypanosoma brucei to isometamidium chloride therapy and the relation to nutrition

Summary

Growing pigs were placed on feeds with high (Group A), medium (B) and low (C) dietary energy and were infected with a virulent stock of T. brucei. Eight weeks later, the infected pigs were treated with isometamidium chloride at 1mg/kg live weight and all pigs were subsequently placed on a high energy diet to investigate their response to therapy.

Clearance of T. brucei from blood was completed 72h after treatment. There was no evidence of relapsed infection up to eight weeks after treatment. Red blood cell parameters returned to normal four to six weeks after treatment with responses being fastest in Group A, B and C had gained about two‐thirds of the live weight gains of their non‐infected pair‐fed controls.

It appears that the retarded weight gain as a result of the infection persisted after therapy since drug‐treated pigs did not gain as much weight as their non‐infected controls.     

A preliminary report on the occurrence of maedi‐visna in sheep in Morocco

Summary

A small scale serological survey for antibodies to maedi‐visna virus among 15 flocks of sheep in Morocco revealed the infection in one flock. Infection appeared to be related with imported sheep. In addition, two abattoir surveys yielded, 0.1% lungs with gross and histological lesions suggestive of maedi.     

Adaptation of a latex agglutination tube test for diagnosis of Mycoplasma hyopneumoniae swine pneumonia

A tube latex agglutination test (LAT) for diagnosis of Mycoplasma hyopneumoniae swine pneumonia was developed. In pigs inoculated with M. hyopneumoniae, LAT antibodies were generally detected 2–3 weeks post-inoculation, which was 1 week or more before complement-fixing antibodies were first detected in the corresponding pigs. Correlation of LAT results and gross and microscopic lung lesions of corresponding pigs revealed that LAT titers persisted after the pneumonic lesions had resolved.Latex agglutination titers in pigs exposed by contact with M. hyopneumoniae inoculated pigs were demonstrated 4–12 weeks post-contact.Latex agglutination antibodies were detected up to 48 weeks post-inoculation in pigs inoculated with M. hyopneumoniae and this was similar to the duration of detectable indirect hemagglutination titers. Complement-fixation titers, however, were demonstrated no longer than 28 weeks post-inoculation in corresponding pigs.Evaluation of repeatability of LAT results revealed some variation of LAT titers of sera titered on four different occasions.Sera from pigs inoculated with other swine mycoplasmas, including M. hyosynoviae and M. hyorhinis, did not react in the M. hyopneumoniae LAT. In addition, no detectable titers were demonstrated in the M. hyopneumoniae LAT using sera from pigs infected with Metastrongylus spp., Ascaris suum, or in sera from pigs vaccinated with any of four commonly used swine vaccines.     

Bovine fasciolosis: coprological, abattoir survey and its economic impact due to liver condemnation at Soddo municipal abattoir, Southern Ethiopia

A study was carried out to determine the prevalence and the species of liver flukes in indigenous adult cattle, to compare the diagnostic efficiency of fecal and post mortem examination and to assess the economic significance of bovine fasciolosis due to liver condemnation in the abattoir. Of the 406 livers and fecal samples examined, 57 (14.0%) and 20 (4.9%) were positive for fasciolosis. The most common liver fluke species affecting the cattle was Fasciola gigantica, 9.1% of cattle were infected with F. gigantica while, Fasciola. hepatica, mixed infections and unidentified or immature forms of Fasciola spp. were present in 3.2 %, 0.7% and 1 % of cattle, respectively. A retrospective abattoir survey revealed that the prevalence of fasciolosis was 12.7%. The prevalence of fasciolosis recorded in this study was lower than that reported by other researchers in this country. There was a strong relationship between fecal examination and postmortem findings of liver lesions, (K?=?0.23) but under local conditions, postmortem examination was considered a better diagnostic tool for fasciolosis. Fasciolosis is of significant economic importance as the resultant liver condemnations caused an average loss of 4000 USD per annum. Hence, this disease deserves serious attention by the various stakeholders in order to promote the beef industry in the study area in particular and in the country in general.     

Serodiagnosis of infections of pigs with Stephanurus dentatus

A serological survey of 135 pigs over 7 months old, some of which had liver and renal lesions in the presence ofStrephanurus dentatus, was undertaken for the presence of antibodies to S. dentatus. Only one sample gave a positive gel immunodiffusion reaction with crude whole worm extracts and none with immunoelectrophoresis. Oral inoculation of pigs with 1200 or 2000 L3 resulted in a specific reaction of anodal lines on immunoelectrophoresis from Day 37, and with double diffusion up to 4 specific lines were produced beginning from Day 43–53 using adult and juvenile antigens. Juvenile antigens gave more intense lines. Serological responses remained positive until 76–80 days post-infection. At necropsy infected pigs had fibrotic lesions in livers and portal thrombi containing larval S. dentatus even after 270 days. It is concluded that immunodiffusion and immunoelectrophoresis have limited usefulness in serodiagnosis of naturally occurring stephanuriasis.     

Mature Ascaris suum in naturally infected calves

In two small farms in Sweden young calves were found to be naturally infected with Ascaris suum. One of the calves expelled mature worms with the faeces, one had a great number of worms in the ductus choledochus and two others had worms in the intestine. Most of the worms were mature and at the egg-producing stage. The morphology of the eggs and the adult worms indicated that these parasites were A. suum and that Toxocara (syn. Neoascaris) vitulorum could be excluded.