Filiform papillae of human, rat and swine tongue

In order to study the structure of filiform papillae (FP), tissue specimens were taken from the anterior part of the tongues of 8 humans, 8 rats and 8 swine. The formalin-fixed samples were processed routinely for scanning electron microscopy (SEM) and light microscopy. With SEM, FP of human tongue contained 5-12 hairs which were covered with a massive plaque of micro-organisms. FP of rat tongue, on the other hand, contained one papillary projection with smooth surface structure. Colonization of micro-organisms was seen on the anterior part of the body of FP, but not on the hairs. In the cross-section of FP of the rat tongue, the cells of the papilla were close to each other and no micro-organisms were seen within the papillae. On the contrary, the spaces between the squamous epithelial cells of the hairs of human FP contained numerous micro-organisms. The structure of FP of the swine tongue resembled that of the rat tongue. The hairs were smooth, and some micro-organisms were seen on the cell surface of the interpapillary areas. The structure of FP is discussed from the standpoint of different keratinization and colonization of micro-organisms.     

Comparison of the human,canine and swine E apoproteins

A comparative study of the E apoprotein isolated from the d<1.02 lipoproteins of human, canine and swine plasma revealed that the various apo-E preparations had similar molecular weights (37,000–39,000) and had similar amino acid compositions in that glutamic acid, alanine, leucine and arginine were present in high concentrations. The various preparations showed partial immunochemical cross-reactivity, demonstrating significant sequence homology between the species. However, determination of the amino-terminal amino acid sequence by automated Edman degradation showed each apo-E was different, demonstrating that the amino-terminal portion of the E apoprotein was a variable region of this protein.     

Relationships between the defensive systems of Iberian-breed swine and the European vector of African swine fever, Ornithodoros erraticus

To discover whether the immune system of Iberian-breed pigs exerts any adverse action on Ornithodoros erraticus, 3 pairs of pigs were subjected to a weekly infestation over 12 wk with 1,000 larvae, 500 nymphs-1, or 200 adults. Each pair was bitten by only 1 developmental stage. Batches of parasites identical to the foregoing ones were fed weekly on control swine. In none of the 10 parameters studied for each of the batches fed weekly was any significant difference found that could be attributed to the state of sensitization of the animals in which, in a previous study, the presence of high titers of anti-O. erraticus antibodies was found. It was observed that the possible pruritus due to immediate hypersensitivity reactions, which in the test animals appeared after the third week, had no protective value in the natural milieu. In view of the inability of the swine to exert any control over the soft ticks, it is concluded that the size of their populations in the pig pens and their composition according to the developmental stage are factors that depend exclusively on the opportunities that swine breeders offer such populations to feed on the animals.     

Mapping of C2, Bf, and C4 genes to the swine major histocompatibility complex (swine leukocyte antigen)

Three miniature swine lines, inbred for swine leukocyte antigen (SLA) haplotypes, a, c, and d, and a recombinant line, haplotype g, were analyzed for possible restriction fragment length polymorphisms (RFLP) by Southern blot hybridization with human C2, factor B (Bf), and C4 specific probes. The search for RFLP by using a human C2 probe failed to reveal any variants. However, a Taq I polymorphism was identified with the human Bf probe and Bam HI and Pvu II polymorphisms were identified with the human C4 probe. Overlapping restriction fragments were found with the C2 and Bf probes, which strongly suggests close linkage of C2 and Bf genes in swine. Segregation analyses of the Bf and C4 polymorphisms indicated that the polymorphic fragments followed a Mendelian pattern of inheritance. The recombinant haplotype g, which expresses class I genes of haplotype c and class II genes of haplotype d, was shown to produce an identical RFLP pattern, by using the Bf and C4 probes, as haplotype d, but different from that of haplotype c. This indicates that there is a close association of [C4-Bf-C2] and class II genes in miniature swine. Although these data do not show conclusively the location of the [C4-Bf-C2] genes, it is hypothesized that swine [C4-Bf-C2] genes are located between the class II and class I genes, as has been demonstrated in mouse and man.     

Ornithodoros porcinus ticks, bushpigs, and African swine fever in Madagascar

African swine fever (ASF) has recently made its appearance in Madagascar. Ticks of the Ornithodoros moubata group, considered to be O. porcinus Walton, 1962 were formerly known to occur in western Madagascar, but seem to have disappeared from that region. However, three new sites where they occur were found in the humid and cool central highlands of Anatananarivo province. These ticks are known to be efficient reservoirs and vectors of ASF and constitute a considerable complication to the control of the disease. The authors also discuss another potentially complicating factor, the presence of a species of African bushpig, Potamochoerus larvatus.     

猪源乳酸菌的分离、鉴定及其生物学特性

【目的】将分离自猪肠道粘膜、食糜和粪便的乳酸菌,通过产乳酸能力、生长性能、耐酸和耐胆盐性能及抑菌能力评价,筛选适应养猪生产的潜在益生特性的菌株。【方法】共分离获得155株乳酸菌纯菌株,从中筛选出4株产酸能力较强的乳酸菌,结合生理生化试验及细菌16S rRNA测序鉴定其种属,评价候选乳酸菌的生长情况、耐酸、耐胆盐及抑菌特性。【结果】综合变色时间(8 h)、pH值(3.9)和乳酸含量(100 mmol/L),筛选出4株(L45、L47、L63和L79)候选菌株,经鉴定依次为罗伊氏乳杆菌、植物乳杆菌、约氏乳杆菌和粪肠球菌。该4株乳酸菌均可在体外快速生长;L47和L79能够耐受pH 2.5的酸性环境,L47能够耐受0.5%胆盐环境;各乳酸菌上清液与指示菌共培养,发现对E coli K88和沙门氏菌均产生了抑制作用,其中L47上清液对指示菌的抑制作用较强。【结论】L47具有较好的产酸性能与生长性能、可耐受猪胃酸和肠道胆盐环境,对E.coli K88和沙门氏菌具有较好的抑制作用,说明该乳酸菌具有潜在的益生特性。     

Survival of Macracanthorhynchus ingens in swine and histopathology of infection in swine and raccoons

Animal husbandry aimed at preventing Macracanthorhynchus hirudinaceus infections in swine is not successful in preventing exposure to Macracanthorhynchus ingens, and it is probable that pigs occasionally acquire acanthocephalans of that species. In some pigs, M. ingens survived 2 weeks and grew several millimeters. In such cases, destruction of villi, erosion of epithelium, leukocytic infiltration, and altered cytological structure at attachment sites accompanied the infection. Penetration was limited to the submucosa, and the effects were not as severe as those occurring in the presence of M. hirudinaceus, which enters the muscularis.     

Cardiac function and morphology of Hanford miniature swine and Yucatan miniature and micro swine

The use of miniature swine in biomedical research is increasing; however, a comparison of cardiac function and morphology between strains has yet to be characterized. The purpose of this project was to examine comprehensive hemodynamics and cardiac morphology of three groups of ten normal, 4 months old, age-matched Yucatan miniature (MINI) pigs, Yucatan micropigs (MICRO) and Hanford (HAN) miniature pigs, 5 males and five females per group. Closed chest cardiac catheterization under equivalent conditions was performed followed by post mortem cardiac morphometry. Mean arterial pressure was significantly greater in the Hanford group when compared to both the minipig and micropig pigs (HAN: 89 +/- 4; MINI: 48 +/- 3; MICRO: 53 +/- 2 mmHg). Pulmonary vascular resistance was significantly different between the three groups (HAN: 9 +/- 1; MINI: 60 +/- 12; MICRO: 111 +/- 29 dyne x sec/cm x m2). The Hanford strain had a significantly smaller heart weight to body weight ratio than the other two groups (HAN: 4.6 +/- 1.0; MINI: 5.7 +/- 0.1; MICRO: 5.5 +/- 1.0). Variations in cardiovascular parameters occur among these strains and should be considered when constructing experimental designs.     

Red cell aggregation and viscoelasticity of blood from seals, swine and man

RBC aggregation and viscoelasticity parameters were determined for 40% suspensions of washed cells in autologous plasma from elephant seals (ES), Mirounga angustirostris, ringed seals (RS), Phoca hispida, and swine, (SS), Sus scrofa. Interspecific comparisons including human (HS) blood data revealed unusual rheological properties of seal blood relative to that from pigs or man: 1) RBC aggregation extent, rate and sedimentation were lower for seals (AI = 0, ZSR = .40, ESR = 0 for RS blood) relative to humans; 2) Viscous (n') and elastic (n") components of complex viscosity (OCRD) were lower for both seal species relative to SS blood, but only at shear rates less than or equal to 10 sec-1 (P less than 0.05), while n"/n' ratios for RS blood were lower than HS blood at all shear rates (P less than 0.01); 3) Blood viscosity measurements for RS and SS blood from rotational viscometry (Contraves) were consistent with OCRD data; 4) Seal plasma fibrinogen levels were low compared to pigs or humans (RS fibrinogen = -43% v. HS and -57% v. SS; ES fibrinogen = -58% v. HS and -69% v. SS). Electrophoretic mobility of RS red cells was +25% relative to those of humans. These results demonstrate differences in hemorheological indices among mammalian species and suggest the value of comparative rheologic studies.