The effect of Pasteurella haemolytica A2 infection on phagocytosis efficiency of caprine broncho-alveolar macrophages

An experiment was designed to study the in vivo effect of Pasteurella haemolytica A2 infection on the phagocytosis activity of caprine broncho-alveolar macrophages and the extent of pneumonic lesions. Twelve healthy local Kacang goats, about 7 months of age, were divided into two groups of six. Goats in group 1 were inoculated intratracheally with 4 ml inoculum containing 2.8 x 10(9) colony-forming units (CFU)/ml of Staphylococcus aureus. Goats in group 2 were inoculated intratracheally with 4 ml of inoculum containing 9.5 x 10(8) CFU/ml of Pasteurella haemolytica A2 isolated earlier from pneumonic lungs of goat. At intervals of 3 and 7 days post-challenge five goats from each group were killed and the lungs were washed with sterile phosphate-buffered saline. Smears were prepared from the lung washing fluid and the number of macrophages with phagocytic activity was determined. At day 3 post-infection, goats of both groups showed a similar pattern of pneumonic lesion. The lung washing fluid of goats in group 2 was found to contain numerous neutrophils and macrophages. Goats in group 2 showed significantly (P < 0.05) higher extent of lung lesions than group 1. Similarly, the average extent of lung lesions was significantly (P < 0.05) more severe in group 2 at day 7 post-infection. The lung washing fluid contained mostly macrophages. The phagocytic activity following S. aureus infection was more efficient and significantly (P < 0.01) higher compared with infection by P. haemolytica A2. There were weak correlations between the extent of pneumonic lesion and the phagocytic activity. Thus, goats with poor phagocytic activity were likely to develop more extensive lung lesions.     

Neonatal osteomyelitis associated with Staphylococcus aureus in turkey poults

A case of Staphylococcus aureus infection causing osteomyelitis in young turkey poults is described. Mortality during the first week after hatching was 12.6%. Poults showed leg weakness, inflammation of all four toes, swelling of feet and hock joints, and osteomyelitis of the proximal tibiotarsus. Staphylococcus aureus was isolated from exudate in the hock joints and footpads. Granulocytic infiltration and colonies of gram-positive coccoid bacteria compatible with S. aureus were found on microscopic examination of the lesions. Toe trimming after hatching is believed to have provided a portal of entry for S. aureus, which resulted in infection of the toes and spread along tendons to joints and bones of the leg. Neonatal staphylococcal osteomyelitis should be considered when recently placed turkey flocks experience increased mortality, especially if they develop severe swelling and inflammation of toes following trimming and have enlarged swollen feet, tendons, or joints.     

Staphylococcus-associated abortions in ewes with long-term central venous catheterization

Forty-two ewes had an intravenous catheter sewn in place in a prepared area over the jugular vein and beginning at 60 days of gestation received an infusion 3 times daily. The infusion consisted of sterile saline or sterile saline containing arginine. Twenty-six ewes in both control and treatment groups aborted between 81 days of gestation and term. Fetuses from 16 ewes that aborted were examined. Most were autolyzed or had early mummification. Macroscopic placentitis and noncollapsing lungs were noted. Large numbers of coagulase-positive Staphylococcus were isolated from fetal abomasal content, lungs, brains, or placentas. Histologically, suppurative placentitis with necrosis and pulmonary aspiration of meconium and amniotic debris often with suppurative bronchopneumonia were observed in abortuses. Four ewes euthanized and examined after abortion had suppurative endometritis. Three ewes had severe, chronic, jugular thrombophlebitis from which coagulase-positive Staphylococcus was isolated. The fourth ewe had mild phlebitis, and Staphylococcus aureus was isolated from both the catheter and the blood. Catheter-associated staphylococcal abortion was diagnosed.     

The use of a new phage set for typing poultry strains of Staphylococcus aureus obtained from seven countries

1. Eighty per cent of poultry strains of Staphylococcus aureus tested from French, Belgian, English, West German, Japanese and Argentinian sources were typable using a set of typing phages isolated in this laboratory. Strains from Bulgaria, however, with few exceptions were not typable with this phage set. 2. Strains isolated from lesions generally resembled those from apparently healthy poultry. 3. The existence of two distinct Staph. aureus biotypes on poultry was confirmed by isolates from six of the countries; one of these biotypes closely resembled Staph. aureus variety gallinae as described by Witte et al. (1977).     

Microbial pathogens from goat mastitis and phage-typing of Staphylococcus aureus isolates

Examination of milk from goats yielded 41 strains from 40 clinically affected halves; 15 were Staphylococcus aureus, 6 Staph. epidermis, 1 Streptococcus agalactiae, 2 Strept. dysgalactiae, 5 Strept. uberis, 2 Corynebacterium pyogenes, 3 Escherichia coli, 3 Pasteurella spp. and 4 Mycoplasma spp. One half had dual infection of Staph. aureus and Strept. dysgalactiae. Twenty two of the 297 milk samples from apparently normal halves also harboured pathogens comprising of 9 Staph. aureus, 1 Strept. agalactiae, 2 E. coli, 2 Pasteurella spp., 2 Candida albicans and 6 Mycoplasma spp. Most of the bacterial isolates were sensitive to many broad spectrum antibiotics. Twenty of the 24 Staph. aureus isolates were phase typable by a set of 23 human Staphylococcal International Phages suggesting the utility of these phages for the typing of goat strains. The isolates were grouped into 15 phage-types, many of which have been reported from human infections in Iraq. This indicates the possibility of association of human strains of Staph. aureus in caprine mastitis. No definite correlation could be noted between antibiogram and phage types of Staph. aureus strains.     

Interstitial pneumonia in feedlot cattle: concurrent lesions and lack of immunohistochemical evidence for bovine respiratory syncytial virus infection.

The objectives of this study were to describe the nature and distribution of microscopic lung lesions in feedlot cattle with interstitial pneumonia and to determine whether bovine respiratory syncytial virus (BRSV) antigen was present in affected lungs. Lungs with macroscopic lesions compatible with interstitial pneumonia were collected from cattle from 5 west-central Saskatchewan feedlots that had been on feed for greater than 60 days at the time of death. Interstitial pneumonia was most consistently present in dorsal portions of caudal lung lobes and in 21/28 cases (75%) had a multifocal to coalescing distribution. All 28 lungs exhibited hyaline membrane formation and some degree of type II alveolar epithelial cell hyperplasia, consistent with an acute to subacute duration. Twenty-one of 28 cases (75%) had concurrent bronchopneumonia in at least 1 lung lobe; bronchopneumonia was grossly evident in 9/28 cases (32%). Chronic bronchitis or bronchiolitis was present in at least 1 section in 12/28 (43%) of the lungs, and 25/28 (89%) had at least 1 focus of bronchiolitis fibrosa obliterans. Bronchopneumonia and bronchiolitis fibrosa obliterans were markedly less common in 10 sets of bovine lungs obtained from an abattoir. Bovine respiratory syncytial virus antigen was demonstrated using immunohistochemistry in 2/28 cases and was associated with bronchiolar epithelial necrosis that was more severe than the bronchiolar lesions in the BRSV antigen-negative cases. Interstitial pneumonia in feedlot cattle in this study was more frequently associated with suppurative bronchopneumonia and bronchiolitis fibrosa obliterans than with BRSV infection.     

An outbreak of erysipelas in 2-day-old poults

Systemic erysipelas infection was seen in 2-to-4-day-old poults from three separate ranches owned by the same company. The affected poults were all from the same breeder source; poults from other breeder sources were seemingly unaffected. Mortality increased on days 2 and 3, ranging from 2% to 8.5%. Birds submitted were dehydrated and very weak, with one half of the poults submitted having died during transport to the lab. Gross lesions included swollen, congested livers and spleens, as well as hemorrhagic breast muscle in one case. Toes were swollen and reddish-purple in color. The poults had been toe-trimmed during hatchery processing using a commercial microwave. Histologically, periportal inflammation with heterophilic infiltration in the liver was noted. Spleens showed hyalinization of arteries, lymphoid depletion, and necrosis. Toe joints showed purulent synovitis and cellulitis. Gram stains done on impression smears of liver and spleen showed rare to moderate numbers of small gram-positive rods. Erysipelothrix rhusiopathiae was isolated from 18 of 22 livers cultured, five of six toe joints cultured, and from the yolk sac in two birds.     

Poliomyelomalacia, pancreatic necrosis, and cerebellar malacia in turkey poults

Two-to-5-week-old turkey poults from three large Minnesota flocks exhibited ataxia, flaccid paralysis, and up to 5% mortality as unexpected death. The major post-mortem finding was cerebellar hemorrhage and softening detected in 22 of 89 clinically affected poults. Histologic findings were severe focal or multifocal poliomyelomalacia in the lumbosacral intumescentia of the spinal cord, cerebellar malacia, and single-cell or multifocal coagulative necrosis of pancreatic acinar cells. Thirty of 32 clinically affected poults examined had microscopic spinal cord lesions, 12 of 48 had cerebellar lesions, and 26 of 47 had pancreatic lesions. Gross and microscopic cerebellar lesions resembled those of vitamin E deficiency in chicks. Hepatic selenium levels were approximately twice normal expected levels for poults.     

The antibiotic resistance of pathogenic staphylococci and streptococci isolated from dogs

The antibiotic resistance of strains of Staphylococcus aureus and beta–haemolytic streptococci of canine origin were assessed against eight drugs using the disc diffusion technique. Of 398 strains of Staph, aureus eight were resistant to neomycin, 15 to ampicillin, 23 to lincomycin, while of 87 streptococci, one was resistant to ampicillin, two to lincomycin and four to penicillin. In addition 4 of 340 Staph, aureus strains tested against cloxacillin were resistant.     

Effects of bacterial coinfection on the pathogenesis of avian pneumovirus infection in turkeys

Four- and nine-week-old poults were inoculated with cell culture propagated avian pneumovirus (APV) into each conjunctival space and nostril, followed by inoculation 3 days later with Escherichia coli, Bordetella avium (BA), or Ornithobacterium rhinotracheale or a mixture of all three (EBO). Clinical signs were evaluated on days 3, 5, 7, 9, 11, and 14 postinoculation (PI) of APV. The poults were euthanatized on days 2, 4, 6, 10, and 14 PI, and blood and tissues were collected. The poults that received APV followed by EBO or BA alone developed more severe clinical signs related to nasal discharge and swelling of intraorbital sinuses than did poults inoculated with APV alone or bacteria alone. More severe pathologic changes were found in poults inoculated with APV+BA that extended to the air sacs and lungs, particularly in 9-wk-old poults. Bordetella avium was recovered from tracheas and lungs of birds that were inoculated with APV followed by EBO or BA alone. APV was detected by immunohistochemical staining in the upper respiratory tract longer in the groups of poults inoculated with APV and pathogenic bacteria than in those that received only APV, particularly when BA was involved. Viral antigen was also detected in the lungs of poults that were inoculated with APV followed by administration of EBO or BA alone. Loss of cilia on the epithelial surface of the upper respiratory tract was associated with BA infection and may enhance infection with APV, allowing deeper penetration of the virus into the respiratory tract.     

Adenovirus infection associated with respiratory disease in commercial chickens

The lesions and etiologic agents associated with 13 outbreaks of respiratory disease in commercial chickens were investigated. Adenoviruses were isolated from tracheal and lung tissues of affected chickens in all 13 outbreaks. Escherichia coli was isolated from the lung of an occasional bird. The tracheal specimens were consistently negative for Bordetella avium, but E. coli and occasionally Staphylococcus aureus were isolated. There was also serological evidence in one outbreak, and pathological evidence in another, of a concurrent infectious bursal disease virus (IBDV) infection of chickens affected with the disease. Gross and microscopic alterations in the tracheas and lungs of affected chickens were similar in all outbreaks and consisted of catarrhal tracheitis and occasionally multifocal pneumonia with mononuclear cell infiltrates. Hepatitis and splenitis with heterophil infiltrates occasionally were seen in birds with coliform septicemia. The tracheal and lung lesions in the present investigation were considered primarily of adenovirus etiology, complicated by secondary bacterial infection.     

呼和浩特地区奶牛隐性乳房炎主要病原菌的分离鉴定及药敏试验

本试验对113份奶牛隐性乳房炎奶样进行细菌分离鉴定、致病性评估及药敏试验。共分离到3大类5种91株细菌，其中金黄色葡萄球菌72株，溶血葡萄球菌8株，表皮葡萄球菌6株；停乳链球菌1株；大肠杆菌2株，沙雷氏菌1株，克雷伯氏菌1株。经过绵羊血溶血试验及小白鼠动物试验，确定部分菌株为致病菌。8类18种药物的药敏试验结果表明，金黄色葡萄球菌和溶血葡萄球菌均对四环素、氯霉素、庆大霉素、卡那霉素等药物高度敏感；链球菌对洁霉素、红霉素、氯霉素、喹诺酮类以及庆大霉素等均高度敏感，肠杆菌对新霉素、磺胺、四环素、链霉素、丁胺卡那、庆大霉素、喹诺酮类等均高度敏感，而对临床上常用的青、链霉素等药物均产生了不同程度的耐药性。     

Evidence for bursal involvement in the pathogenesis of hemorrhagic enteritis of turkeys

The pathogenesis of hemorrhagic enteritis in turkey poults infected with hemorrhagic enteritis virus (HEV) at 3 days or at 2 or 5 weeks of age was compared with pathogenesis in poults that had been chemically bursectomized neonatally and exposed to cell-culture-propagated virus at 2 or 5 weeks of age. Conventional poults exposed to HEV at 2 or 5 weeks developed clinical disease, and mortality ranged from 38% to 100%. In addition to the splenic and intestinal lesions usually seen with HEV infection, the pancreas, bursa of Fabricius, and thymus were also affected. In contrast, although they were free from detectable maternal antibody, poults infected with HEV at 3 days of age failed to develop clinical disease or mortality; however, virus was demonstrated by histological and electron microscopic examinations in spleens of these poults. Neonatal chemical bursectomy completely prevented the clinical signs, gross lesions, and mortality induced by HEV in poults at 2 or 5 weeks of age. These findings strongly suggest that an intact bursa is necessary for HEV to induce disease in turkeys.     

Passively administered antibodies alleviate stunting syndrome in turkey poults

Stunting syndrome is an enteric disease of young turkeys that results in reduced growth (stunting) of poults and impaired feed efficiency. A virus, which has been termed the stunting syndrome agent (SSA), causes stunting syndrome. In this study passive immunity was evaluated as a method of protecting poults from stunting syndrome. One-day-old poults were injected with either tryptose phosphate broth, an anti-SSA antibody preparation, or an anti-Newcastle disease virus antibody preparation before challenge by placing them into SSA-contaminated isolators or control (nonchallenge) isolators. Poults that received anti-SSA antibodies were significantly heavier (P < 0.05) and did not display as severe clinical disease compared to birds that did not receive the anti-SSA antibodies. However, the birds that received anti-SSA antibodies and were challenged were significantly lighter (P < 0.05) than birds that were not challenged. The results of this trial demonstrate that the injection of anti-SSA antibodies benefited poults undergoing stunting syndrome. The role of passive immunity, either through breeder hen vaccination or through supplying antibodies to poults artificially (i.e., at the hatchery), may have future applications in alleviating stunting syndrome.     

Macrolid resistance in Staphylococcus aureus strains from chicken synovitis and dermatitis in industrial production

In outbreaks of synovitis and dermatitis in chicken caused by Staphylococcus (Staph.) aureus we observed erythromycin-resistant strains. These strains belong to the host-specific variety gallinae of Staph. aureus or can not be alloted to one of the known host-specific varieties. The macrolide-resistance-determinant is not carried by a plasmid, presumably it is located on the chromosome. The strains show constitutively cross-resistance to erythromycin, thurimycin, linomycinc and pristinamycin (M-L-S-phenotype). An ecological investigation in a chicken farm has shown that there is no distribution of Staph. aureus-strains from chicken to workers and no occurence of macrolide-resistance in Staph. aureus-strains from the workers.     

Preliminary studies on bacterial interference of staphylococcosis of chickens

Previous studies indicated that Staphylococcus epidermidis strain 115 might be an effective interfering agent in reducing the rate of staphylococcosis in turkeys. In the present study, strain 115 was avirulent when administered to 3-day-old chicks by oral, aerosol, or intravenous route. Strain 115 adhered specifically to tracheal, lung, air-sac, and liver cells in vitro and interfered with subsequent colonization by virulent Staphylococcus aureus. In vivo colonization of lungs and livers of young chicks occurred following exposure to aerosols of strain 115. Strain 115 interfered with the in vivo colonization of lungs and livers by virulent S. aureus.     

Some features of coagulase positive staphylococci from bovine milk. II. Comparison of conventional techniques and the API Staph system

A total of 150 isolates of Staphylococcus aureus were subjected to the tests on the API Staph system. Of these, 50 were also tested by conventional methods, using the same tests as those found on the API Staph strips. Applying the principles of numerical taxonomy, the relationship between these isolates was 82% and more. Tests for the metabolism of sucrose and N-acetyl-glucosamine and for the production of argenine dihydrolysate and urease appear to be superfluous in the identification of S. aureus in this system.     

Enhanced virulence of Staphylococcus aureus from bovine mastitis induced by growth in milk whey

The virulence towards mice of Staphylococcus aureus strains from bovine mastitis was enhanced upon growth in milk whey compared to homologous organisms grown in tryptic soy broth (TSB). In the mouse mastitis model, S. aureus grown in milk whey caused more severe lesions than homologous strains grown in TSB. Staphylococcus aureus strain F1440 grown in milk whey induced 75% mortality and local necrotic reaction in subcutaneously inoculated mice, whereas the homologous strain grown in TSB caused only 5% mortality and slight skin reaction. Extracellular capsule on milk whey-grown, S. aureus could not be demonstrated. However, diffuse type colony morphology could be correlated with an increased virulence of S. aureus towards mice.     

Salt poisoning in turkey poults

A 4% mortality in 5-to-11-day-old turkey poults was attributed to 1.85% sodium chloride in the feed. The syndrome included peracute respiratory distress, ascites, and sudden death that resembled peracute heart failure. Clinical signs were observed only in the final phase of the toxicity, but progressive histologic lesions were found. Live, apparently unaffected poults showed increases in intracellular glycogen and cytoplasmic granularity, loss of striation, and early mild intercellular myocardial edema; similar but more severe histologic lesions were seen in live, ascites-affected poults. The ascites-affected poults had hydropericardium and hydrothorax which seemed to develop just minutes before death. Ultrastructurally, focal areas of myocardial cells exhibited myofibrillar disarray, lysis of myofilaments, widened Z-bands, and dilation of sarcoplasmic reticulum.     

Effects of adjuvant-augmented germling vaccines in turkey poults challenged with Aspergillus fumigatus

Turkey poults were vaccinated with combinations of two different germling preparations and three adjuvants (N-acetylmuranyl-L-alanyl-D-isoglutamine, Pasteurella multocida lipopolysaccharide [LPS], and avridine) at 1 and 2 weeks of age, and their immunity was challenged by sublethal exposure to aerosols of Aspergillus fumigatus conidia at 1 month of age. Fewer turkeys in the groups given vaccines prepared from germlings grown on Dorset's and Henley's medium (D&H) had organisms in lung tissue at 2 weeks after challenge exposure as compared with those vaccinated with germling grown on neopeptone dialysate (Neo). The LPS of P. multocida appeared to be the most efficacious of the adjuvants in the D&H vaccine group, as A. fumigatus was isolated from only one of eight turkeys in this group; the number of organisms per gram of lung tissue was low compared with other vaccine groups at 2 weeks after challenge exposure; and poults given D&H vaccine with LPS as adjuvant had less-severe lung lesions than other groups. These differences in lung lesions were more marked at 2 weeks than at 8 weeks after challenge exposure. The only difference among other parameters in the vaccinated turkeys was lower heterophil counts in the turkeys given D&H-prepared vaccines than in unvaccinated controls. This was probably due to less-severe infections resulting from protective effects of these vaccines.