Morphological studies on the heart ventricle of African catfish (Clarias gariepinus)

The histological and ultrastructural characteristics of the heart ventricle in Clarias gariepinus (African catfish) has been studied by light microscopy and transmission electron microscopy. The ventricle of the heart has a saccular shape and the myocardial wall consists of an outer thin compact myocardium and an inner well-developed spongy myocardium. The myocardial layer has small myocytes, interstitial spaces and blood vessels. The myocytes are the major constituents of the ventricular wall. They are long cells, with large nuclei, and predominantly euchromatin. The sarcoplasmic reticulum of the ventricular myocytes consists of a network of tubules and subsarcolemmal cisternae oriented mainly along the longitudinal axis of the myofibrils. In contrast to the ventricular structure of other fish species described in the literature (Greer-Walker et al., 1985; Santer, 1985; Sánchez-Quintana et al., 1995, 1996), the African catfish, a freshwater sedentary fish recently introduced in neotropical climatic environments, showed a saccular ventricle that consisted of two muscle layers, a thin compact layer with large vessels and a developed spongy layer. The ultrastructure of the ventricular myocardium of C.gariepinus is similar to that of other teleosts, inclusive that of fish with other swimming habits.     

Antibody‐Dependent Killing of Virus‐Infected Targets by NK‐Like Cells in Bovine Blood

Natural killer (NK) cell lysis of target cells by an Fc receptor‐mediated mechanism has not been conclusively demonstrated in cattle (Campos and Rossi, Vet. Immunol. Immunopathol. 8, 351–362, 1985), although it is well recognized in other species (Sulica et al., Nat. Immun. 14, 123–133, 1995). To resolve this problem, bovine peripheral blood mononuclear cells were completely depleted of adherent monocyte/macrophage type cells. The resulting enriched population of lymphocytes, was totally devoid of adherent monocytes, but contained up to 2 % NK‐like cells. On their own, this population had very low background levels of cytotoxicity for virus‐infected target cells in ⁵¹chromium release assays, but following the addition of virus‐specific antibodies, high levels of lysis were observed. This enhanced level of antibody‐dependent cytotoxicity demonstrated that bovine NK‐like cells can mediate killing of targets by an Fc receptor‐mediated mechanism as has been demonstrated for NK cells from other species.     

Genetic parameters of production and fertility traits in Hungarian Merino sheep

Hungary has a long-standing tradition in Merino breeding and improvement. During the past decades several attempts have been made to introduce a number of other sheep breeds. Although this effort was not in vain the majority of the sheep population is still the Hungarian Merino breed. The adaptability, endurance and excellent wool-producing ability of this breed is first rate and is worth preserving (V eress et al. 1997). The profitability of a sheep production system is determined by both fertility and production traits. Reproduction performance is usually defined as litter weight per dam per year. Progress can be achieved through various ways. One of them is frequent lambing which also has the advantage that lamb production becomes more consistent throughout the year. Another possibility is producing larger litter sizes (LS), and yet a another opportunity for increased production is having lambs with larger weights (WT). Simultaneous enhancement can also be achieved if there is no antagonism between these traits. From these several fertility traits LS from the first to the fifth parity was chosen for analysis as LS is one of the most important traits concerning reproduction performance. Of the production traits, WT measured at various ages, greasy fleece weight (GFW) from the first five shearings, staple length (SL) and fibre diameter (FD) at the age of 1 year were taken into the analysis. According to other studies there are several factors influencing the above mentioned traits, namely age, season of previous lambing (PLS), type of birth (TOB), and sex. In general, LS increased with advancing age (L ong et al. 1989; B unge et al. 1990; A p D ewi et al. 1996). For GFW the peak of production was achieved in a relatively early age of 3 years, reported by V eress (1969) and by T urner and Y oung (1969). The effect of PLS on LS was that smaller litters were observed with previous lambing seasons of summer and autumn (L ong et al. 1989). TOB and sex effect on WT have been investigated by several authors (T urner and Y oung 1969, p. 46, 51.; S hrestha and H eaney 1985; M avrogenis 1988; B unge et al. 1990; J urado et al. 1994; V eress et al. 1995; S hrestha et al. 1996). Single-born lambs are heavier than multiples although this difference decreases with age. All authors also agree that male lambs are heavier than females. TOB and sex effect on GFW were reported by T urner and Y oung (1969). T urner and Y oung labelled the TOB effect as a ‘maternal handicap’ as the effect is noticeable even in maturity but decreasing by age. T urner and Y oung (1969) also observed that the WT and GFW of male animals exceeds that of the females, but, unlike with the previous effect, the difference increases with age. There was a negligible difference between sexes in SL and FD. Studying the results of numerous authors, estimates of the genetic parameters of LS, WT, GFW, SL, and FD were found to be generally consistent. Heritabilities of LS ranged from 0.05 to 0.08 (A l -S horepy and N otter 1996; A p D ewi et al. 1996; for litter size at first parity only). A p D ewi et al. (1996) found very high (>0.9) genetic correlations between the first and adult litter size. Heritabilities estimated for WT were higher than those of the fertility traits and ranged in the interval of 0.05–0.47 (S hrestha and H eaney 1985; L ong et al. 1989; B unge et al. 1990; K umar and R eheja 1993; J urado et al. 1994; A l -S horepy and N otter 1996). Genetic correlations between yearling and adult WT were high (J urado et al. 1994; 0.85; A l -S horepy and N otter 1996; 0.85–1.0). GFW heritabilities reported by B lair et al. (1985); T urner and Y oung (1969) were about 0.2 thus also exceeding those of the fertility traits. Regarding the genetic parameters of SL & FD, N otter and H ough (1997); M orris et al. (1996) reported that the heritability of SL and FD was higher than that of GFW (026–0.34; 0.47–0.58). Genetic correlations among production traits were mainly low (M orris et al. 1996; and T urner and Y oung 1969). The objectives of this paper were to determine whether the characteristics of the Hungarian Merino sheep population correspond with the features given in the literature review. Thus the objectives were to obtain the factors influencing the traits examined and to estimate genetic parameters of LS, WT, GFW, SL, and FD, respectively.     

Cell proliferation of feline and human breast cancer cell types is inhibited by pomegranate juice

Mammary cancer, a devastating disease in both humans and companion animals, has been associated with numerous factors including diet. Polyphenolic antioxidants found in pomegranate fruits have been shown to reduce tumor burden and inhibit angiogenesis and cell growth.(Kim et al., 2002; Afaq et al., 2005; Malik et al., 2005) Feline mammary carcinomas (FMC) are known to have similar invasive behavior, histologic appearance, and overall poor prognosis to estrogen receptor negative (ER-) invasive human mammary cancer.(Porrello et al., 2004; Zappulli et al., 2005) In this study, supplementation with an antioxidant-rich whole food (pomegranate) was evaluated for anti-cancer properties in an ER- human breast cancer cell line (MDA-MB-231) as a model for FMC. Antioxidant capacity and polyphenolic content of pomegranate juices (PJ) were characterized by reportable methods. ER- cells were exposed to PJ at various concentrations (0.5%, 1%, 5%) and to Cisplatin (5 ug/ml, 10 ug/ml, 15 ug/ml) doses for 48 and 72 h. MTT assays were performed to evaluate the ability of PJ to inhibit tumor cell growth. Statistical significance was determined using PROC GLM (SAS 9.1) with alpha = 0.05. Cell proliferation of the ER- cancer cells was inhibited by pomegranate juice in a dose- and time-dependent manner (p < 0.0001). Maximal inhibition was seen for pomegranate juice formulations at the 5% dose, and the response was comparable to that of high-dose Cisplatin. This first phase study shows that PJ may be a useful nutrient-based, non-chemotherapeutic treatment alternative for the inhibition of ER- breast cancer cell proliferation.     

Individual antigens of cattle. Bovine CD2 (BoCD2).

The data obtained in the workshop provide further evidence that CH128A and IL-A26 and the 12 new mAbs that form a cluster recognise the bovine orthologue of CD2. The mAbs inhibit rosetting with SRBC, stain cells in primary and secondary lymphoid organs in patterns consistent with those obtained in humans with anti-CD2 mAbs, and the 11 IgG mAbs all immunoprecipitate a peptide with a Mr of 58-62 kDa. It is not clear from the studies whether the epitopes defined by the mAbs correspond with the region I and II epitopes present on CD2. None of the data suggest that any of the mAbs recognise the region III (CDD2R) epitope (Peterson and Seed, 1987; Knapp et al., 1989). Further studies are now needed to define the physical and functional relation of the epitopes and establish whether antibody-mediated activation corresponds with that noted in humans. Data reported in one study (Baldwin et al., 1988) with IL-A26 suggest possible differences in the requirements for activation. In addition, further studies are needed to demonstrate how many cell types express BoCD2. In mice, evidence has been presented which shows the mouse orthologue is expressed on some B cells (Yagitta et al., 1989). Studies in cattle have clearly shown CD2 is present on the majority of CD4+ and CD8+ T-cells and a small population of CD4-/CD8- cells (Baldwin et al., 1988; Davis, unpublished observations). Evidence presented in this workshop has shown that some CD2+ cells express a WC2 molecule (Sopp et al., 1991).(ABSTRACT TRUNCATED AT 250 WORDS)     

Dysgenesis atypica ovarü bei einer XY-Kalbin. Histologische, biochemische, genetische und Rezeptor-Befunde

Inhalt: Die Phänomene der gonadalen Dysgenese weisen eine erhebliche Bandbreite au Die hier vorgestellte XY-Kalbin hatte ein geringgradig hypoplastisches, weibliches Genitale, in den dysgenetischen Gonaden lagen 2 Primordialrestfollikel vor. Ihre inter-stitiellen Zellen waren hyperplastisch, doch gab es keine Anzeichen für eine tumoröse Entartung, in Art eines Gonadenblastoms oder Dysgerminoms. Das Tier hatte zur Behandlung der bestehenden primären Amenorrhoe keine Hormonbehandlung erfahren. Die Konzentrationen uon Sexualsteroiden (Testosteron, Epitestosteron, Dehydroepian-drosteron) glichen solchen, wie sie im Zyklus des Rindes auftreten, ein Konzentrations-anstieg nach Pregnylapplikation war nichtzu erzielen. Nucleare Rezeptoren für Dihydro-testosteron waren nicht nachzuweisen. Die Persistenz von einzelnen Follikeln und von Keimzellen in den postpartalen resp. postpubertären Gonaden wurde in den letzten Jahren beim Menschen gelegentlich beschrieben, ist jedoch fur die reine gonadale Dysgenese nicht charakteristisch. Contents: Dysgenesis atypica ovarii in a XY-heifer The phenomena of gonadal dysgenesis show a wide range of variations. The XY-heifer described in this article showed low grade of hypoplasia of the inner female genital organes. Two primordial residual follicles were detected in serial sections of the dysgenetic gonads. The interstitial cells were hyperplastic, but there was no indication of tumorous degeneration, such as gonadoblastoma or dysgerminoma. No hormones had been given to treat primary amenorrhoe. Levels of sexual steroids (testosterone, epitestosterone, dehydroepiandrosterone were similar to those occurring in normal bovine cycle; Pregnyl failed to produce any rise in the concentration of sexual steroids. No evidence was found of nuclear receptors for dihydrotestosterone. Persistence of singular follicles and germinal cells in the postpartal and postpubertary gonads resp. of XY females has been sometimes observed (Cussen & Mac Mahon, 1979; Russel et al., 1980; Warner et al., 1985), but this is — by no means —characteristic for pure gonadal dysgenesis.     

Eosinophils: A review

The eosinophil was discovered by Jones in 1846 (Dessein and David, 1982) but its proclivity to stain with aniline dyes was first described by Paul Ehrlich in 1879 (Hirsch and Hirsch, 1980). Recognized and named for this quality, eosinophils possess an abundance of highly basic proteins within their granules which confer their affinity for acidic dyes (Gleich and Loegering, 1984).Eosinophils are traditionally viewed as killer-effector cells in parasitic infestations and as modulators of Type I hypersensitivity reactions (Butterworth and David, 1981; Kay, 1985). The eosinophils' reserve of cationic proteins and enzymes which imparts their profound parasiticidal effects (Butterworth and David, 1981) contrasts with this leukocyte's purported regulatory function in inflammation (Kay, 1985; Fechteret al., 1986). The opposing functions possessed by this leukocyte exemplify the enigma of the eosinophil. Recent evidence suggests that although the eosinophil does possess some regulatory capabilities, its presence is, in fact, a harbinger of tissue destruction (Gleich and Adolphoson, 1986, Wardlaw and Kay, 1987; Spry, 1988). Nor does the presence of the eosinophil automatically infer IgE mediated hypersensitivity, as evidenced by studies examining the interaction of the eosinophil with the cellular arm of the immune system (Basten and Beeson, 1970; Ruscettiet al., 1976; Beeson and Bass, 1977; Raghavacharet al., 1987; Ohnishiet al., 1988).The purpose of this review is to provide a brief overview of the structure and biology of the mammalian eosinophil and to emphasize the fact that eosinophils fulfil a paradoxical role as effectors of tissue damage and as benign modulators of inflammation.     

Etiopathogenetic defect of malignant hyperthermia: Hypersensitive calcium-release channel of skeletal muscle sarcoplasmic reticulum

Summary and conclusions Overwhelming clinical, physiological, pharmacological, and biochemical evidence indicates that MH occurs due to a genetic defect of intracellular calcium homeostasis in skeletal muscle. Specifically, the balance of data clearly and plausibly implicates the channel through which calcium is released from the terminal cisternae of sarcoplasmic reticulum as the site of the underlying molecular lesion of MH. This putative channel is commonly believed to be ligand-gated, that is, opened by the binding of specific agonists (Meisner, 1984). Apparently, the gating of the MH channel is abnormally sensitized, that is more tightly coupled than normal, to the binding of agonists such as calcium (and ATP). Consequently, the MH channel requires less trigger calcium or ATP for activation.Caffeine may act as weak agonist of the putative, purinergic (ATP) receptor of the ligand-gated calcium channel of the sarcoplasmic reticulum (Meisner, 1984).Persistent elevations of myoplasmic free calcium in the vicinity of the channel, which would be subliminal for normal muscle, may trigger massive and regenerative calcium-induced calcium-release in MHS muscle. Uncontrollable and sustained activation of the contractile apparatus and metabolic machinery follows. The source of the trigger calcium may be the lumen of the transverse tubules via their voltage-gated calcium-channels (Ikemoto et al., 1984; Curtis & Catteral, 1984; Graf & Schatzmann, 1984), dislodged calcium from binding sites on the inner leaflet of the transverse tubular membrane (Frank, 1979; Curtis & Eisenberg, 1985), or the lumen of the terminal cisternae of sarcoplasmic reticulum via their ligand-gated calcium channels.Such persistent, but normally subliminal, elevations of trigger calcium at the site of the calcium-release channel presumably occurs in MHS muscle with administration of potent volatile anesthetics, especially halothane, and depolarizing muscle relaxants, especially succinylcholine. The gaseous anesthetics apparently act indirectly on the calcium channel by virtue of their being potent but non-specific membrane perturbing agents (Ohnishi et al., 1986) which increase the passive permeability of the sarcoplasmic reticulum, and possibly surface membrane, to calcium.In individuals which are homozygous for the genetic defect the less potent muscle stimuli of anoxia, heat, and exertion may be sufficient to increase the local trigger calcium concentration to a level resulting in uncontrollable calcium-release. Such homozygosity occurs rarely in people but commonly in swine due to inbreeding and the high frequency of the MH gene. Homozygosity for the MH gene may explain the occurrence of porcine (Topel, 1968), human (Wingard, 1974), and canine (O'Brien & Rand, 1985) stress syndromes: a double dosage of the genetic defect may render homozygotes hypersensitive to stimuli less potent than volatile anesthetics.Dantrolene, the MH-preventive and reversing (if administered early enough in the syndrome) drug, apparently acts by a different mechanism than drugs such as ruthenium red and the amide local anesthetics which appear to physically block the pore of the ligand-gated calcium channel (Ohnishi et al., 1986). Dantrolene's effect on the calcium channel is apparently indirect. It blocks the membrane-perturbing effects of halothane (Nelson & Denborough, 1977; Ohnishi et al., 1986) perhaps by stabilizing muscle membranes and therefore their calcium channels (voltage-gated in transverse tubules and ligand-gated in terminal cisternae). However, this muscle relaxant is less effective at inhibiting the calcium-releasing effects of calcium or caffeine probably because these act directly on the calcium channel (Nelson & Denborough, 1977; Nelson, 1984; Britt et al., 1984; Araki et al., 1985; Ohnishi et al., 1986).Modelling the MH defect as a hypersensitive calcium-release channel also provides a plausible explanation for observations of gradations of susceptibility to triggering of MH for individuals and within populations (Gronert, 1980; Ellis & Heffron, 1985). This model predicts gradations due to gene dosage (homozygous versus heterozygous) as well as due to environmental, pharmacologic, and genetic factors which would compromise or challenge calcium homeostatic potential, such as: heat, anoxia, exertion, drugs which stimulate muscle, and other myopathies.Thus, MH is initiated due to a hypersensitive calcium-release mechanism of skeletal muscle sarcoplasmic reticulum. Malignant hyperthermia may be reversed by dantrolene and symptomatic treatment up until a critical irreversible point in the development of the syndrome. This point of irreversibility probably corresponds to the occurrence of significant degenerative structural and functional changes within the muscle fiber. Loss of calcium-sequestration capabilities by sarcoplasmic reticulum is likely the most important factor which contributes to the irreversibility of MH.     

Whole-body protein turnover and nitrogen balance in growing pigs supplied with an antibiotic feed additive (Avilamycin)

Introduction   Antibiotic feed additives like Avilamycin (Maxus^®) exert a well-documented stimulatory effect on growth rate and feed efficiency in pig production (reviewed by, e.g., R oth and K irchgessner 1990; K amphues and M eyer 1992). The benefits to production performance seem to originate mainly from an enhanced gain of body protein as has been demonstrated in nitrogen balance trials with piglets and fattening pigs (R oth and K irchgessner 1993a,b; W indisch et al. 1998). However, the primary mode of action of antibiotic feed additives is not clarified completely. The growth-stimulating effect is assumed to originate from an enhanced absorptive capacity of the digestive tract for essential nutrients due to an improved microbial ecosystem in the gut (reviewed by, e.g., G reife and B erschauer 1988). However, metabolic effects may contribute to the higher protein accretion capacity also, as for example a reduced immune defense stress at the small intestine for example (discussed by, e.g., S chole et al. 1985). In order to elucidate possible metabolic effects of antibiotic feed additives it was the aim of the present study to combine a nitrogen balance experiment on Avilamycin-treated growing pigs with measurements on whole-body protein turnover.     

贵州发现黑颈长尾雉(Syrmaticus humiae)

Introduction Hume’s Pheasant (Syrmaticus humiae), including two subspecies, is distributed in northeastern India, Myanmar, northern Thailand and southwestern China (Collar et al., 2001). In China its distribution has been assumed to be restricted to Yunnan and northwestern Guangxi (Mackinnon et al., 2000; Zheng, 2011).     

The humoral immune response of rainbow trout (Salmo gairdneri) immunised by various regimes and preparations of Aeromonas salmonicida antigens

Antibody production in rainbow trout to extracellular antigens was investigated. The following antigen preparations and immunisation regimes were used: native extracellular products (ECP) in Freund's complete adjuvant (FCA), intraperitoneally (i.p.) with and without booster; formalinized ECP in FCA, i.p. with and without booster; washed, formalinized A. salmonicida cells in FCA, i.p., with booster; native ECP in saline, i.m., four weekly injections at two different doses, 45 micrograms and 6 micrograms each injection (after the protocol of Shieh, 1985). Using crossed normal rainbow trout serum, i.p., single injection (after the protocol of Sakai, 1985). Using crossed immunoelectrophoresis all antisera contained precipitating antibodies to three to five ECP components except that from fish immunised i.m. with 6 micrograms protein where antibodies were undetectable. In no case were specific antibodies to ECP protease or haemolysin detected. In a rabbit immunised with formalinized ECP in FCA under a similar regime to the rainbow trout, antibodies to at least 15 ECP components, including protease and haemolysin, were detected. The assumption of a specific immune response to the protease, at least in respect of antibody production, in recent reports of protection afforded by vaccines composed of either crude ECP or partially purified protease (Shieh, 1985) or partially purified protease inactivated by normal serum (Sakai, 1985) is not supported by the present findings.     

Transport stress--consequences for bacterial translocation, endogenous contamination and bactericidal activity of serum of slaughter pigs

On transport and at the abattoir animals are confronted with a lot of stressors, such as sound/noise, crowding/mixing, pollutants and infectious agents that act on the organism. After transport stress an endogenous contamination is often seen in slaughter carcasses and presents a hazard for the consumer. These events are often correlated with a rise in endotoxin level (Misawa et al., 1995; Morales et al., 1992) and a modified immune response. Previous own investigations confirm this hypothesis (Zucker and Krüger, 1998, Seidler et al., 2000). The attempt was made to investigate the impact of selected stressors (short term transport (1 h), long term transport (7-8 hrs), high temperature, high humidity and intense handling/moving) on bacterial translocation, endogenous contamination, endotoxin levels and bactericidal activity of body fluids.     

Antigenic characterization of mycobacteria from South American wild seals.

Tuberculosis-producing mycobacteria have been previously described in marine mammals (Cousins et al., 1990, 1993; Romano et al., 1995; Bernardelli et al., 1996). The strains belonged to the M. tuberculosis complex (M. tuberculosis, M. bovis, M. microti and M. africanum), but showed genetic and biochemical differences. The antigenic composition of mycobacteria isolated from wild seals was analyzed by Western blots, using antibodies against some selected antigens. The antigenic content was compared with that of M. bovis, M. tuberculosis and M. microti isolates. The lack of Hsp65 protein in supernatants suggested a low degree of cell lysis in the three-week cultures used. SOD, P27 lipoprotein, MPB64 and antigen 85 were observed in all the strains studied. The wild seal strains, as well as M. tuberculosis, did not produce MPB70 and MPB83. Only very weak bands of P36 antigen were observed in culture supernatants from wild seal mycobacteria. Summarizing, the antigenic composition of mycobacterial strains from wild seals is different from M. bovis strains.     

Evaluation of equations to predict body composition in Nellore bulls

The equations developed by Hankins and Howe (1946, HH), Marcondes et al. (2010, M10), Marcondes et al. (in press, M11) and Valadares Filho et al. (2006, V6) were evaluated to predict the body composition from the 9–10–11th rib cut in Nellore bulls. The evaluated equations estimated the physical and the carcass chemical composition, the empty body chemical composition and the noncarcass chemical composition. Thirty-seven Nellore bulls (14±1 months old initially) with shrunk body weight of 259±24.9 kg were used in this experiment. The bulls were randomly divided into three groups: five bulls to the reference group, four bulls were fed at maintenance level and twenty-eight bulls were fed ad libitum. The bulls fed ad libitum were separated into four groups, one of which was slaughtered every 42 days. The diet was composed of corn silage and concentrate (55:45). After slaughter, the 9–10–11th rib cut was dissected into muscle, fat and bone fractions. The remaining carcass was similarly dissected. The others parameters that were evaluated as partial predictors included the empty body weight, the dressing percentage, the visceral fat percentage, the organ and viscera percentage and the composition of the noncarcass components. The values estimated with prediction equations were compared to the observed values. The equations obtained by M11 predicted correctly the carcass physical composition. However, the muscle and fat tissues were under- and overestimated, respectively, by HH. Some constituents of the noncarcass components can be predicted from equations developed by M10. The equations obtained by M10 predicted correctly the carcass and empty body chemical composition. The carcass water was underestimated by HH. The equations by V6 did not predict the carcass or empty body chemical composition. The carcass physical and chemical composition and empty body chemical composition can be predicted from the composition of 9–10–11th rib cut by equations obtained by Marcondes et al., 2010 and MarcondesPlease complete and update the reference given here (preferably with a DOI if the publication data are not known): Marcondes et al. (in press). For references to articles that are to be included in the same (special) issue, please add the words ‘this issue’ wherever this occurs in the list and, if appropriate, in the text. et al., while the composition of these components cannot be predicted by Hankins and Howe (1946) and Valadares Filho et al. (2006) in Nellore bulls.     

A new cell culture protocol for enrichment and genetic modification of adult canine Schwann cells suitable for peripheral nerve tissue engineering

Easily applicable techniques are presented to obtain high numbers of enriched canine Schwann cells (cSC) in a short time-window. The potential of adult SC for tissue engineering of peripheral nerves and ex vivo gene therapy is obvious from physiological events taking place after peripheral nerve transection [Haastert, K., Grothe, C., 2007. Gene therapy in peripheral nerve reconstruction approaches. Curr. Gene Ther. 7, 221-228]. The presented techniques were modified from a protocol for cultivation and expansion of adult cSC by others [Pauls, J., Nolte, C., Forterre, F., Brunnberg, L., 2004. Cultivation and expansion of canine Schwann cells using reexplantation. Berl. Munch. Tierarztl. Wochenschr. 117, 341-352] and own experiences in rodent and human SC cultivation and transfection [Haastert, K., Mauritz, C., Chaturvedi, S., Grothe, C., 2007. Human and rat adult Schwann cell cultures: fast and efficient enrichment and highly effective non-viral transfection protocol. Nat. Protoc. 2, 99-104]. A purity of about 80% cSC achieved by immunopanning techniques and selective culture conditions is 2.5 fold higher as previously reported (Pauls et al., 2004). Additionally, highly enriched cSC populations are available in 3-4 weeks, only half the time period reported previously (Pauls et al., 2004). Furthermore, electroporation and genetic modification of cSC is reported for the first time.     

Immunohistochemical study of angiogenesis and angiogenic factors in equine granulosa cell tumours

The first part of our study (Müller et al., 2009) characterized angiogenesis in the equine cycling ovary through histomorphological and immunohistochemical examinations (vascular endothelial growth factors A and B [VEGF A, VEGF B], vascular endothelial growth factor receptors 1 and 2 [VEGF-R1, VEGF-R2], vascular angiopoietins 1 and 2 [Ang1, Ang2], angiopoietin receptor [Tie2], and von Willebrand Factor). Since angiogenesis plays an important role in development and growth of numerous tumours, the second part of our study involved a similar examination of 70 equine granulosa cell tumours (GCTt). The results of the second study were compared with those of the normal equine ovary. Certain similarities in the expression pattern could be detected between normal, cyclical ovaries (Müller et al., 2009) and GCTt. The immunoreactivity of granulosa cells and Leydig-like cells in GCTt resembles granulosa cells and luteinized thecal cells in periovulatory cycling ovaries. The neoplastic cells support circulation, supply and growth of GCTt by contributing to angiogenesis.     

Determination of polyethylene during the process of measuring feed passage rate in sheep

In a trial with rams, application of polyethylene powder (PE) as a marker for determination of feed passage rate through the digestive tract and three methods of its determination in feed and feces were tested. PE with particle size 0.4 mm and specific weight 0.924 was administered to animals in feed and its excretion was studied during the period of 10 days in two experimental diets based on secondary sources of wood, and in one control diet. PE formed 3.9% (D-2), 3.5% (D-1) and 4% (control) of the diet dry matter and was determined by gravimetric method; for mineralizing organic matter in the sample, nitric acid (Chandler et al., 1964), mixture of sulphuric and nitric acid (Kemmink and Dijkstra, 1968) and sodium hydroxide (Boling et al., 1967) were used. The most suitable was the method using sodium hydroxide, by which 81.23% (D-2), 84.78% (D-1) and 86.6% (control) of PE recovery was determined in feces samples.     

Evidence of a specific dietary selection for lysine by the piglet

The ability of animals to appropriate sources of food and select among them to obtain a nutritionally adequate diet that is best suited for their physiologic status has been examined in numerous species, but considerable research has addressed self-selection trials with chicks. Observations on diet preference have led to the assumption that birds have an innate ability to regulate their intake of macro- and micronutrients, and that they can do so with a considerable degree of precision (e.g. Holcombe et al. 1975, 1976; Elkin et al. 1985; Harper and Peters 1989; Emmerson et al. 1991; Steinruck et al. 1991a,b; Steinruck and Kirchgessner 1993a,b,c; Shariatmadari and Forbes 1993; Forbes and Shariatmadari 1994, 1996). Experimental evidence also shows that domesticated pigs which are offered a choice between two diets will select a diet containing an adequate amount of protein in preference to one that is deficient in protein, or will select specific proteins among various protein sources (Robinson 1974; Kyriazakis et al. 1990; Kyriazakis and Emmans 1992, 1993; Bradford and Gous 1992; Roberts and Azain 1997). The characteristic amount of a specific protein selected by the animals appeared to be related to the quality of the protein source. This was obvious from a few amino acid selection studies showing that growing-finishing pigs have the ability to select preferentially amino acid-adequate diets over amino acid-deficient diets within a few days (Devilat et al. 1970; Robinson 1975a,b; Davey 1978; Henry 1987, 1993). In contrast, there are also some exceptions to the hypothesis that selection of diet is related to the nutritional quality of the protein fed (Ashley and Anderson 1975). However, some of those studies are not conclusive due to changes in preferences by the animals over time and differences in protein source, palatability and amino acid pattern between the test diets. Since, an investigation of a self-selection behaviour by piglets has rarely been studied in detail, the purpose of this research was to determine whether piglets that are given a choice of diets with high or low lysine contents can regulate the intake of each to optimize lysine intake and performance. The objectives of this study were to determine the preference of piglets for diets varying in lysine content and to determine whether the preferences for these diets change with time. This indispensable amino acid was selected for study because it is first limiting in conventional diets for growing pigs.     

The characteristics and regulation of glutamate dehydrogenase in strains of Bacteroides ruminicola ssp. ruminicola isolated from the rumen of fallow deer]

Very little information about NH4+ assimilation paths in rumen anaerobic bacteria is available, and the information about wild animals is completely missing. Glutamate dehydrogenase (GDH) isolated from the rumen strain B. ruminicola in fallow deer was purified and its properties were specified after crystalline ammonium sulphate precipitation and gel filtration on Sephadex G-200. The properties of partly purified GDH were specified. One of the first specifications concerning GDH from various sources was to determine its coenzyme specificity. The results of these determinations enabled to draw a general conclusion that GDH from non-animal sources was specific to only one coenzyme while GDH from animal sources could utilize the two coenzymes (Frieden, 1964). In our study the specificity of GDH isolated from the rumen strain B. ruminicola in fallow deer to the coenzyme NADH (Tab. I) was determined; this specificity was different from the coenzyme specificity of GDH isolated from the rumen strain B. ruminicola in calves where GDH was found to be specific to the coenzyme NADPH. The effect of increasing concentrations of NADH, 2-oxoglutarate and NH4+ on the enzyme reaction velocity was also investigated and Km was determined for NADH, 2-oxoglutarate and NH4+ (Tab. II). The kinetic properties of GDH isolated from different sources are considerably variable. Michaelis constants for GDH range from 0.003 to 0.125 mmol/dm3 for NADPH (NADH), from 0.95 to 7.4 mmol/dm3 for 2-oxoglutarate, and from 0.25 to 16 mmol/dm3 for NH4+ (Misono et al., 1985). The average value of Km for NH4+ in a mixed rumen population was 33 mmol/dm3 (Erfle et al., 1977).(ABSTRACT TRUNCATED AT 250 WORDS)     

Pluripotent stem cells--model of embryonic development,tool for gene targeting,and basis of cell therapy

Embryonic stem (ES) cells are pluripotent cell lines with the capacity of self-renewal and a broad differentiation plasticity. They are derived from pre-implantation embryos and can be propagated as a homogeneous, uncommitted cell population for an almost unlimited period of time without losing their pluripotency and their stable karyotype. Murine ES cells are able to reintegrate fully into embryogenesis when returned into an early embryo, even after extensive genetic manipulation. In the resulting chimeric offspring produced by blastocyst injection or morula aggregation, ES cell descendants are represented among all cell types, including functional gametes. Therefore, mouse ES cells represent an important tool for genetic engineering, in particular via homologous recombination, to introduce gene knock-outs and other precise genomic modifications into the mouse germ line. Because of these properties ES cell technology is of high interest for other model organisms and for livestock species like cattle and pigs. However, in spite of tremendous research activities, no proven ES cells colonizing the germ line have yet been established for vertebrate species other than the mouse (Evans and Kaufman, 1981; Martin, 1981) and chicken (Pain et al., 1996). The in vitro differentiation capacity of ES cells provides unique opportunities for experimental analysis of gene regulation and function during cell commitment and differentiation in early embryogenesis. Recently, pluripotent stem cells were established from human embryos (Thomson et al., 1998) and early fetuses (Shamblott et al., 1998), opening new scenarios both for research in human developmental biology and for medical applications, i.e. cell replacement strategies. At about the same time, research activities focused on characteristics and differentiation potential of somatic stem cells, unravelling an unexpected plasticity of these cell types. Somatic stem cells are found in differentiated tissues and can renew themselves in addition to generating the specialized cell types of the tissue from which they originate. Additional to discoveries of somatic stem cells in tissues that were previously not thought to contain these kinds of cells, they also appear to be capable of developing into cell types of other tissues, but have a reduced differentiation potential as compared to embryo-derived stem cells. Therefore, somatic stem cells are referred to as multipotent rather than pluripotent. This review summarizes characteristics of pluripotent stem cells in the mouse and in selected livestock species, explains their use for genetic engineering and basic research on embryonic development, and evaluates their potential for cell therapy as compared to somatic stem cells.