Serodiagnosis of canine leptospirosis by solid-phase enzyme-linked immunosorbent assay.

An enzyme-linked immunosorbent assay (ELISA) to detect antibodies to Leptospira interrogans serotype canicola in dogs was developed and evaluated. Comparison of the ELISA with the microscopic agglutination test (MAT) showed that, during the first two weeks after an experimental infection with serotype canicola, the ELISA detected antibody at higher dilutions than the MAT. After the second week post-infection both tests detected antibody at almost equal titres (r = 0.89). The outer envelope (OE) antigen of serotypes icterohaemorrhagiae, copenhageni and canicola was fairly serotype-specific, whereas the pellet (P) antigen showed more cross-reactivity. Both OE and P antigen of Leptospira biflexa strain Patoc I could be used as cross-reacting antigen in the ELISA. Compared to the MAT, the ELISA has some technical advantages. It is suggested that the ELISA would be useful as a screening test.

Determination of specific anti-leptospiral immunoglobulins M and G in sera of experimentally infected dogs by solid-phase enzyme-linked immunosorbent assay.

The development and evaluation of an enzyme-linked immunosorbent assay (ELISA) to detect specific anti-leptospiral IgM and IgG in sera of dogs experimentally infected with Leptospira interrogans serotype canicola are reported. In all dogs specific anti-leptospiral IgM was detected from the second half of the first week after infection, the maximum being attained during the second week. Subsequently the IgM titre gradually decreased. Specific anti-leptospiral IgG was detected later and increased gradually to reach almost the same level as the IgM titre after two to three months. During the initial stage of the infection, when the microscopic agglutination titre was still negative or very low, a high IgM titre was accompanied by a negative or very low IgG titre in every case. After the initial stage a substantial IgG titre was also detectable. It is suggested that the test is suitable for serodiagnostic purposes, particularly for the diagnosis of a current infection in an individual.

K88 variants K88ab, K88ac and K88ad in oral vaccination of different porcine adhesive phenotypes. Immunological aspects.

Sows of different adhesive phenotypes were vaccinated orally during the last 4 weeks of gestation with K88-positive Escherichia coli. Sows susceptible to adhesion by the K88 variant of the vaccination strain produced a significant IgA-class specific anti-K88 response in colostrum and milk and post-farrowing serum. Indications for an IgM and IgG-class specific anti-K88 response were also found in this group but only in milk. In sows resistant to adhesion by the K88 variant of the vaccination strain only an IgA-class specific anti-K88 antibody response was found in mammary secretions and in post-farrowing sera, but titres did not reach the high values of the former group. The response in the second group was attributed to the frequent administration of large quantities of K88-positive E. coli which to some extent can be compared with a colonization effect. Specificity for the serological components of the K88 variants was detectable in colostral IgA of sows susceptible to the vaccination strain only.

Humoral immune response of dogs after vaccination against leptospirosis measured by an IgM- and IgG-specific ELISA.

An IgM- and IgG-specific ELISA was used to measure the antibody response stimulated in dogs by vaccination with a leptospiral bacterin containing chemically inactivated Leptospira interrogans serotype icterohaemorrhagiae and serotype canicola leptospires. All dogs produced anti-leptospiral IgM and IgG. The IgM production was of the primary response type after each vaccination (primary vaccination, booster vaccination and annual revaccination). A substantial anti-leptospiral IgG response could be demonstrated only after the first booster vaccination and the annual revaccination. Annual revaccination resulted in a higher and much longer persisting IgG response than did the first booster vaccination. A revision of the vaccination scheme is suggested.

Haemagglutination patterns of the different variants of Escherichia coli K88 antigen with porcine, bovine, guinea pig, chicken, ovine and equine erythrocytes.

Determination of the porcine adhesive phenotype was not achieved by haemagglutination (HA) of porcine erythrocytes, which in all cases were agglutinated by K88ab and K88ad, independent of the adhesive phenotype as determined by the brush border adhesion test. K88ac always gave negative HA results with porcine red cells. However, HA appeared to offer a method of differentiating between the K88 variants without monospecific antisera. K88ab agglutinated porcine, guinea pig and chicken erythrocytes; K88ac agglutinated only guinea pig red cells and K88ad produced haemagglutination with porcine and guinea pig erythrocytes.

The prevalence of different porcine phenotypes in the Netherlands concerning adherence of K88-positive Escherichia coli to intestinal epithelium.

Jejunal brush border samples from 101 pigs were tested for the presence of K88 receptor sites. Specific adhesion of K88-bearing microorganisms did not occur in nearly 50 percent of the samples. About 40 percent of the test samples were adhesion positive for the prevailing K88ac antigen. The different porcine phenotypes were equally distributed over the country.

Swine dysentery in a sow herd. I. Clinical manifestation and elimination of the disease with a combination of lincomycin and spectinomycin.

An acute outbreak of swine dysentery (Doyle) on a farrowing farm is described. Besides clinical signs of enteritis a general loss of condition was seen throughout the herd. This resulted in a decreased fertility and breeding performance among sows and an increase in piglet mortality. Several dehydrated sows aborted. The outbreak was stopped by oral treatment with lincomycin/spectinomycin 1:1. In the course of the treatment all animals and buildings were washed and disinfected. The use of pharmacotherapeutics in treating swine dysentery is discussed with emphasis on the involuntary induction of carriers.

[Comparison of the sensitivity patterns of Staphylococci isolated from bovine udders in 1974 and 1980]. / Een vergelijking van het gevoeligheidspatroon van staphylococcen geïsoleerd uit runderuiers in 1974 en 1980.

In 1974 (1973-1975) the Minimum Inhibitory Concentrations (MIC) for 693 strains of staphylococci isolated from bovine udders originating either from the national randomized mastitis survey (A) or from farms with mastitis problems (B) were determined. The antibiotics used were penicillin, nafcillin, cloxacillin, neomycin, streptomycin, lincomycin, novobiocin, rifamycin and chlortetracycline. In 1980, 370 strains from the randomized survey were examined for the same antibiotics plus cephalonium, kanamycin and quinaldofur. The proportion of strains originating from the randomized surveys showing a MIC for penicillin higher than 0.16 1. U./ml, was 35.6 per cent in 1974 and 34.1 per cent in 1980. Only minor changes were observed for the majority of other drugs studied. Despite the continued use of antimicrobial drugs in the treatment of mastitis, changes in the sensitivity of staphylococci were not observed since 1974.

Plasma concentrations, plasma protein binding and residues of sulfamonomethoxine in pigs, horses and cattle.

The protein binding, the plasma half-life and the residue depletion of sulfamonomethoxine (SMM) after intramuscular administration were investigated in pigs, horses and cattle. Protein binding was weakly concentration-dependent. The bound fraction in plasma in the therapeutic range amounted to approximately 45, 40 and 50% for pigs, horses and cattle respectively, and the plasma half-lives were approximately 5.1, 5.7 and 3.1 hours respectively. SMM levels were less than 1 mug/g in muscle tissue after 36, 20 and 12 hours in pigs, horses and cattle respectively. In the kidney SMM levels were not less than 1 mug/g until 48, 60 (extrapolated) and 36 (extrapolated) hours respectively. In pigs and horses SMM residues in the injection site were extremely variable. In cattle, SMM disappearance from the injection site was more regular. SMM concentrations in pig, horse and cattle liver remained more or less constant in the latter part of the period investigated.

[Polyarthritis in calves (author's transl)]. / Polyarthritis bij kalveren

The development of polyarthritis was studied in thirty-six calves. Thirty patients were from two to eleven days of age; six animals were older than eleven days. Besides clinical studies, the synovial fluid was examined both biochemically and bacteriologically in addition, a blood culture was made. When the synovial fluids of twenty-six calves were studied bacteriologically, P. multocida was isolated in ten cases, P. haemolytica in two cases, E. coli in ten cases, streptococci in three cases and D. pneumoniae in one case; bacteriological examination of the synovial fluid was negative in ten cases. Blood cultures were positive in twenty animals (P. multocida in five cases, P. haemolytica in two cases, E. coli in eleven cases, S. subacidus in one case and D. pneumoniae in one case). Twenty-five calves were treated by intra-articular as well as intramuscular injection of kanamycin (sulphate); six animals were treated with similar injections of ampicillin. Treatment with ampicillin was initially instituted in five calves; after some time, however, kanamycine (sulphate) was substituted for this medication. Twenty-seven calves recovered completely.

[Some epidemiological features of salmonellosis in veal calves in the Netherlands (author's transl)]. / Enkele epidemiologische aspecten van salmonellose bij mestkalveren in Nederland.

In the Netherlands, salmonellosis in veal calves is caused by S. dublin and S. typhimurium. Strains showing multiple drug resistance are important factors in these cases. Strains of S. typhimurium isolated from dead veal-calves resistance are important factors in these cases. Strains of S. typhimurium isolated from dead veal-calves are confined to a small number of phage types (mainly X 200, X 210, X 193, X ORS). To trace the Salmonella organisms to their origin, faecal samples were collected from one week old calves in markets, in lorries and within 24 hours after their arrival on veal-calf units, and subsequently examined for the presence of Salmonella. Salmonella (47.5 per cent of S. typhimurium, 20 per cent of S. dublin and 32.5 per cent of other serotypes) was isolated from 3.5 per cent of the individual faecal samples of 1,143 calves on seven veal-calf farms (1976-1978). Clinical symptoms caused by S. typhimurium and the other serotypes were not observed on these farms, whereas there were individual cases due to S. dublin. The phage types of S. typhimurium isolated (I 650, VI 260 and II 505) obviously had little if any pathogenic significance in calves. During the period from October 1977 to November 1978. Salmonella was isolated from nearly 6 per cent of 1,880 calves in the markets (S. typhimurium 50 per cent, S. dublin 17 per cent and other serotypes 33 per cent). Well over 25 per cent of the strains of S. typhimurium isolated were of the pathogenic phage types (X 201, X ORS). Salmonella was isolated from well over 30 per cent of eighty-three lorries. It is concluded that markets and lorries are important factors in the epidemiology of salmonellosis in veal calves. However, there also are persistent infections in veal-calf units. Possible routes of infection, in which the veal calf is regarded as the most important source of infection, are discussed. More detailed epidemiological studies are in progress to make it possible to suggest measures by which the incidence of salmonellosis in the Netherlands may be reduced.

Biochemical and immunological characterization of cell surface proteins of Pasteurella multocida strains causing atrophic rhinitis in swine.

In a previous paper (B. Lugtenberg, R. van Boxtel, and M. de Jong, Infect. Immun., 46:48-54, 1984) we showed that among 34 isolates from swine the membrane protein and lipopolysaccharide (LPS) patterns, as analyzed by sodium dodecyl sulfate-gel electrophoresis, could be classified into three and six patterns, respectively. In all cases a certain LPS pattern was correlated with a certain protein pattern. Certain combinations of types of cell surface proteins and LPSs were correlated with pathogenicity, the latter property being judged by the guinea pig skin test. In the present paper the immunological and biochemical properties of cell surface constituents were analyzed. The reaction between electrophoretically separated cell surface constituents with guinea pig and sow antisera showed that LPS as well as several proteins were immunogenic. Among these is protein H, whose electrophoretic mobility is the main criterium for typing of cell envelope protein patterns. Protein H was the most heavily labeled component when whole cells were iodinated by the Iodo-Gen procedure showing its accessibility at the cell surface. These properties of protein H make it an attractive vaccine candidate. Further biochemical analyses revealed that protein H shares many properties with pore proteins of members of the family Enterobacteriaceae. One of these properties, association between pore proteins and peptidoglycan, was used as the basis for a simple procedure developed to partially purify protein H.

Different pig phenotypes affect adherence of Escherichia coli to jejunal brush borders by K88ab, K88ac, or K88ad antigen.

At least five different porcine phenotypes were distinguished with the three serological variants of the K88 antigen in the brush border adhesion test. Pigs of one phenotype (A) are susceptible to adherence of all three variants, pigs of three phenotypes are susceptible to only two (B and C) or one (D) of the K88 variants, and pigs of one phenotype (E) are entirely resistant to adhesion of K88 antigen did not interfere with the adhesion of K88ab- or K88ac-positive Escherichia coli, whereas in most cases K88ab and K88ac antigen completely blocked the adhesion of K88ad-positive E. coli. Likewise, K88ab antigen blocked the adhesion of K88ac-producing E. coli to both type A and type B brush borders, and vice versa.

Serological identification of pig enterotoxigenic Escherichia coli strains not belonging to the classical serotypes.

Escherichia coli strains isolated from pigs suspected to have succumbed to E. coli enterotoxicosis and not belonging to the commonly incriminated (classical) serotypes (O8:K87:K88, O45:K88, O138:K81:K88, O141:K85:K88, O147:K89:K88, O149:K91;K88, and O157:K88) were tested for enterotoxigenicity in the ligated gut test (LGT) using pig intestine. Of 202 strains tested, 54 strains belonging to 13 different O groups were positive in the LGT. Four of these strains had K88 antigen and one possessed K99 antigen. The majority of the strains was not agglutinated by any of the standard OK antisera. Four new K antigens ("K200", "K442", "K2346" and "K2347") were provisionally designated. K200 was found in pig enterotoxigenic strains belonging to O group 8 and carrying flagellar antigen H31 and in non-enterotoxigenic non-motile strains of O group 8, as well as in O group 20 strains isolated from calves succumbing to E. coli septicemia in two countries. The provisional antigen K2346 was encountered in 18 enterotoxigenic strains with various O antigens from two countries. It is proposed to include these two K antigens into the international E. coli antigens scheme. Attempts to demonstrate a common antigen in the nonclassical enterotoxigenic strains lacking K88 and K99 antigens failed.

Streptococcal pharyngitis and epiglottitis in a newborn infant.

We describe a newborn infant with Streptococcus sanguis septicaemia and concomitant upper airway obstruction due to epiglottitis and pharyngitis. This rare infection of the supraglottic region was treated with endotracheal intubation and antibiotics. Full recovery occurred within 4 days.