Immunohistochemical detection for Actinomyces sp. in swine tonsillar abscess and granulomatous mastitis

Ultrasonography and Infrared Thermography as a Comparative Diagnostic Tool to Clinical Examination to Determine Udder Health in Sows

Simple Summary

The udder health of sows is most important to raise healthy piglets. The aim of the study was to investigate a possible advantage of infrared thermography and ultrasonography over the clinical examination of the udder of sows. For this purpose, both clinically healthy sows with inconspicuous udders on palpation before and after birth (n = 35) and sows at the time of weaning (n = 107) were examined. Images of thermography and ultrasound revealed no pathological alterations in the clinically healthy sows. A physiological statistically significant increase in the udder surface temperature and the thickness of the parenchyma during the three weeks ante partum was observed. After weaning, abnormalities in the appearance of roundish nodules of the parenchyma were detected sonographically in 10.3% of the examined sows, while the demonstrated nodules were unrecognised clinically in two out of eleven sows. The changes could also be demonstrated thermographically because of a statistically significant lower surface temperature above the nodules compared to the remaining skin of the mammary gland. However, scratches on the udder skin showed similar temperature changes. Therefore, thermographic images without prior inspection of the udder can lead to misinterpretation.

Abstract

The aim of the study was to examine whether the use of infrared thermography and ultrasonography can complement or replace the clinical examination of the sows’ mammary glands for pathological alterations. Sows of different parities with inconspicuous udders on palpation before and after birth (n = 35) and sows at the time of weaning (n = 107) were examined. Thermal images were taken from both sides of the udder, while ultrasound pictures were taken from four sides of the respective mammary glands. Within three weeks before birth, a statistically significant increase in the average surface temperature of the glands of about 1.54 °C and of the thickness of the parenchyma of about 1.39 cm could be observed. After weaning, in 10.3% of the examined sows, roundish hyperechogenic nodules were detected sonographically in the glands´ parenchyma. The average skin temperature above the nodules was 1.24 °C lower compared to the total skin area of the altered complex. However, scratches on the udder skin showed similar temperature changes. In two sows, the nodules remained undetected during the clinical examination. Therefore, sonography seems to be superior compared to clinical and thermographic investigations, although it proved to be very time-consuming.

Actinomyces denticolens as a causative agent of actinomycosis in animals

The name "Actinomyces suis" was applied to each actinomycete isolate from swine actinomycosis by Grässer in 1962 and Franke in 1973. Nevertheless, this specific species was not included in the "Approved List of Bacterial Name" due to absence of the type cultures. Therefore, "Actinomyces suis" based on the description of Franke 1973 has been considered as "species incertae sedis". We isolated a number of Actinomyces strains from swine. The representative strains of them was designated as Chiba 101 that was closely similar to the description in "Actinomyces suis" reported by Franke in 1973. Interestingly, it was found that the biological characteristics of these strains were also very similar to those of Actinomyces denticolens. Furthermore, the average nucleotide identity (ANI) value between strain Chiba 101 and the type-strain of Actinomyces denticolens (=DSM 20671^T) was found to be 99.95%. Sequences of the housekeeping genes and 16S rRNA gene showed 100% homology. These results strongly suggested that "Actinomyces suis" Franke 1973 is the same species as Actinomyces denticolens. Since actinomycosis caused by Actinomyces denticolens have been demonstrated in horses recently, it is necessary to recognize that Actinomyces denticolens is the pathogenic actinomycetes in broader range of animals.

Whole-Genome Sequences of Two Closely Related Bacteria, Actinomyces sp. Strain Chiba101 and Actinomyces denticolens DSM 20671T

Actinomyces sp. strain Chiba101, isolated from an arthritic leg joint of a pig raised in Japan, is a bacterium closely related to Actinomyces denticolens Here, we deciphered the complete genome sequence of Actinomyces sp. Chiba101 and the high-quality draft genome sequence of A. denticolens DSM 20671^T.

Actinomyces denticolens colonisation identified in equine tonsillar crypts

Recently, submandibular abscesses associated with Actinomyces denticolens have been reported in horses. The actinomycotic clumps have been observed in the tonsillar crypts. The aim of this study was to demonstrate colonisation of A denticolens in equine tonsils. Twelve equine tonsils obtained from a slaughterhouse were divided into two parts for histopathological examination and for isolation of A denticolens. When actinomycotic clumps were found in these tonsillar crypts, immunohistochemistry using hyperimmune serum against A denticolens (DMS 20671) was performed on the serial sections. To determine whether Actinomyces-like bacteria isolated using immunoantigenic separation technique were A denticolens, the isolates were analysed for the 16S rRNA gene sequence. Actinomycotic clumps were found in the tonsillar crypts of 11 (91.7 per cent) horses. The clumps were of the saprophytic type accompanied with the feedstuffs, but a few clumps were surrounded by inflammatory cells. A denticolens antigens were immunodetected not only in the clumps of 11 (100 per cent) tonsils, but also in the tonsillar parenchyma. Six isolates obtained from four tonsils showed 99.7–99.9 per cent similarity to A denticolens in the 16S rRNA gene sequence. In horses, the colonisation sites of A denticolens are the tonsils, thus the authors suggest that the tonsils provide the intrinsic infection site for A denticolens.

Tonsilliphilus suis gen. nov., sp. nov., causing tonsil infections in pigs

A micro-organism resembling members of the genus Dermatophilus, strain W254(T), which was isolated from the submandibular lymph node of a pig, and an additional 16 strains isolated from swine tonsils, were studied to establish their taxonomic status. Although all 17 strains were isolated anaerobically under an atmosphere of 100 % CO2, all of them were aerotolerant anaerobes. The micro-organisms showed at least five cellular morphologies: (i) a radially protrusive thallus, which proliferated into tuber-like cells; (ii) segmentation in both tubers and thallus followed by multilocule formation, (iii) development of coccoid forms in the locules; (iv) a change from the coccoid forms to zoospores; (v) resting cells, which were able to develop into protrusive thalli again. The micro-organisms were positive for nitrate reduction, but negative for catalase, indole production, hydrolysis of urea and gelatin liquefaction. Milk was not decomposed and none of the strains was haemolytic. A total of 16 compounds, including glucose, were utilized as sole carbon sources and seven compounds, including l-arabinose, were not utilized. Three out of the 17 strains were subjected to further studies. The micro-organisms had meso-diaminopimelic acid in their peptidoglycan and galactose, glucose, madurose and a trace of mannose in their whole-cell sugar patterns. The major phospholipids were phosphatidylglycerol, diphosphatidylglycerol and phosphatidylinositol.Cellular fatty acids were C15 : 0 (35.7-23.1 %), C16 : 0 (5.9-2.4 %) C17 : 0 (62.9-39.5 %), C17 : 1 (24.4-0 %) and C18 : 0 (3-1.6 %). The predominant menaquinone was MK-8 (H4). The G+C content of the DNA was 69.6-71.8 mol%. Analysis of the 16S rRNA gene sequences showed that the strains clustered with the type strains of members of the family Dermatophilaceae. Based on the polyphasic taxonomic characterization carried out, all 17 strains are considered to belong to a novel species in a new genus, for which the name Tonsilliphilus suis gen. nov., sp. nov. is proposed. The type strain of the type species is W254(T) ( = ATCC 35846(T) = CCM 3774(T) = DSM 21880(T) = JCM 15727(T)).

Aborted lesions of a pig associated with Arcanobacterium abortisuis and the immunohistochemical features

A microorganism isolated from an aborted sow's placenta has been proposed as a novel species, Arcanobacterium abortisuis. The lesions in the placenta were suppurative and necrotic placentitis, whereas lesions of three fetuses were suppurative bronchopneumonia. Gram and Grocott-positive organisms in these lesions were immunolabeled with anti- Arcanobacterium abortisuis antibody. This is the first case report, which showed the association of Arcanobacterium abortisuis with the aborted lesions of a pig.

Actinomyces hyovaginalis-associated lymphadenitis in a Nubian goat

A 6-year-old Nubian goat with a history of progressive weight loss and cough was presented for necropsy. The goat tested negative for antibodies to caseous lymphadenitis and caprine arthritis and encephalitis by hemagglutination inhibition assay and enzyme-linked immunosorbent assay, respectively. Postmortem examination revealed marked enlargement and, with histopathology, a fibrinopurulent necrotizing lymphadenitis of a tracheobronchial lymph node, with an appearance similar to that reported in cases of caseous lymphadenitis. An organism characterized by molecular methods as Actinomyces hyovaginalis was isolated together with Staphylococcus spp. and Streptococcus spp. from the lesion. No Corynebacterium pseudotuberculosis was recovered. To the authors' knowledge, this is the first isolation of A. hyovaginalis from a goat. Although the exact contribution of A. hyovaginalis to the lesion remains to be established, this case demonstrates that A. hyovaginalis should be considered in cases of caseous lymphadenitis-type lesions, especially when C. pseudotuberculosis has been excluded.

Pathology of udder lesions in sows

In recent years an increasing frequency of sows with udder lesions has been observed during meat inspection. The frequency and pattern of affected mammary complexes were determined by inspection, palpation, and incision of udders of 640 sows at a local slaughterhouse. From representative lesions, tissue specimens were sampled for histological and bacteriological examination. Moreover, in seven problem cases immunohistochemistry was applied for the identification of Staphylococcus aureus and Arcanobacterium pyogenes. Udder lesions were recorded in 67 sows (10.5%), with mammary complex no. 7 being most frequently affected (39%). In most cases (81%), lesions were restricted to a single mammary complex. Gross lesions were characterized as focal or multiple abscesses, which most often (79%) were accompanied by dermal ulcerations. Based on histological observations and bacterial identification, two groups of lesions were identified: (I) pyogranulomatous lesions of the dermal and subcutaneous tissue caused by S. aureus; and (II) dermal and subcutaneous abscesses dominated by A. pyogenes. In neither group I nor group II lesions, the glandular mammary tissue was involved as demonstrated by immunostaining for cytokeratin, i.e. mastitis was not diagnosed in any of the cases. In conclusion, all udder lesions were caused by skin infections predominantly caused by A. pyogenes and S. aureus resulting in the development of dermal abscesses and pyogranulomatous lesions, respectively.

[Tonsillar hypertrophy and mesenteric adenopathies as the main manifestations in a patient with Whipple's disease]

Whipple's disease is an infrequent chronic infection caused by Tropheryma whipplei, identified in 1992. Intestinal, articular, central nervous system and cardiac involvement is common. The presence of abdominal adenopathies, especially mesenteric adenopathies, without peripheral adenopathies or gastrointestinal, articular, neurological or cardiac symptoms is rare. We present the case of a male patient with tonsillar hypertrophy, mesenteric adenopathies, fever and constitutional syndrome, leading to suspicion of lymphoma. Biopsy findings of the lingual tonsil and mesenteric adenopathies were compatible with Whipple's disease. The diagnosis was confirmed by blood polymerase chain reaction.

Partial characterization of the antigen recognized by a monoclonal antibody to Ascaris suum ovary extracts

A monoclonal antibody produced against ovary extracts from the worm Ascaris suum showed immunoreactivity against granules in the rachis and oocytes, the inner layer of the eggshell and the middle layer of some egg, but not against either ovary wall or uterus wall. Furthermore, the same antigens were detected on the body surface of migrated larva in guinea pig lung, whereas none were detected in adult male worm or adult female worm, except for the female reproductive organs. The ovary extracts were passed through an affinity column and the eluted fractions analyzed by SDS-PAGE, Western blotting and native-PAGE. Western blotting after SDS-PAGE detected chemiluminescence primarily as three bands of about 70, 78 and 90 kDa. However, Western blotting after native-PAGE of the partially purified ovary extracts demonstrated only one band at a position of about 230 kDa. LC-nanoESI-MS/MS analysis of protein band gel slices from silver-stained SDS-PAGE revealed one peptide sequence "ILVGLIGTNR", that matched only the hypothetical protein F14D2.8 of Caenorhabditis elegans (gi/7499081).

Hemorrhagic Necrotizing Splenitis in a Slaughter Pig Infected with Arcanobacterium Species

A 6-month-old barrow presented with lethargy, inappetence and dysstasia. At necropsy, multiple coalescing hemorrhagic foci were detected in the margins of the spleen. Gram-positive bacilli were isolated from the spleen, kidney, muscle and liver. Comparative 16S rDNA gene sequencing analysis of the isolates (TO16177) revealed that they would be the same species of unpublished Arcanobacterium species strain HJ57-14E (accession no. gi 18873551) (99.7% similarity based on a comparison of 675 bp). Histologic examination of the splenic tissue sections revealed extensive necrosis and inflammation, and gram-positive bacilli were discernible. Multifocal necrosis was also detected in the liver. Immunohistochemically, the isolates were cross-reacted with polyclonal antibodies against Arcanobacterium pyogenes and Actinomyces naeslundii, and the reaction was strong for the latter. Similar reactions were found in the suppurative lesions of the tonsil, and occasionally in the spleen and lymph nodes. The present results indicate that the unpublished Arcanobacterium species induced multiple organ failure accompanied by acute hemorrhagic necrotizing splenitis in this growing-finishing pig.

Clinical characteristics, prevalence, influence on sow performance, and assessment of sow-related risk factors for granulomatous mastitis in sows

OBJECTIVE

To determine the prevalence and clinical appearance of granulomatous mastitis in sows, to identify sow-related risk factors for development of granulomatous mastitis, and to explore the manner in which the disease influences sow performance.

ANIMALS

1,254 sows from 76 herds.

PROCEDURE

A clinical examination was performed at time of weaning and 7 days later. In addition, some sows were reexamined at time of weaning in the subsequent lactation. Data were collected on sow performance.

RESULTS

At time of weaning, 205 of 1,254 (16%) sows had granulomatous mastitis, and 7 days later, the prevalence was 19%. Variation between herds was large (0 to 50%). In most of the affected sows (156/205 176%]), only 1 mammary gland was affected. Parity, duration of lactation, and number of teat wounds were identified as risk factors for development of the disease. In 264 of 559 (47%) sows (38/104 [37%] mammary glands), a granuloma recurred in the subsequent lactation. Risk for recurrence was related granuloma appearing in multiple form but not to granuloma size. Affected glands were less distended in the subsequent lactation, suggesting lower milk production. Litter size appeared to be negatively affected by the disease.

CONCLUSIONS AND CLINICAL RELEVANCE

Granu lomatous mastitis is a common disease in sow herds maintained on straw bedding and in group housing, and it has negative effects on sow productivity. A thorough description of the clinical appearance of the disease and the identification of risk factors should contribute to development of relevant control measures.