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21.
The purpose of this work was to define more precisely the role of Ureaplasma organisms in the aetiology of granular vulvovaginitis and balanoposthitis (GVVBP) of cattle. To contribute to this question the frequency and degree of infection with Ureaplasmas in two main groups of cattle was taken into account: (a) in cattle with symptoms of the mentioned disease, (b) in cattle without clinical symptoms. The samples of semen from 301 sires with symptoms of GVVBP and from 43 healthy sires as also vaginal mucus swabs from 96 cows with GVVBP and from 40 cows mated by the sire infected with Ureaplasma organisms and from 50 cows inseminated with semen which contained Ureaplasma organisms were taken for bacteriological examinations. The control group in relation to the above mentioned cows constituted of 22 heifers free from symptoms of GVVBP and neither inseminated nor mated naturally. It has been shown that on an average 78.1% of sires with pathological changes in the mucosa of the penis or prepuce and only 25.6% of healthy sires were infected with Ureaplasma organisms. The concentration of Ureaplasma organisms was also significantly higher in material obtained from sires with symptoms of the disease than in that from healthy animals. Ureaplasma organisms were demonstrated more frequently (72.7%) in cows with GVVBP than in cows without these symptoms (13.3%). Similarly, as in the material obtained from sires, in the material taken from cows with symptoms of the disease the concentration of Ureaplasma organisms was significantly higher than that in the material originating from the healthy cows. The obtained findings may indicate that Ureaplasma organisms play a role in the aetiology of GVVBP.  相似文献   
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23.
In earlier in vitro experiments opioids affected steroidogenesis in porcine luteal and granulosa cells. The present studies were undertaken to examine the effects of FK 33-824 (opioid agonist) alone or in combination with LH, PRL or naloxone (NAL, opioid antagonist) on steroidogenesis in cultured porcine theca cells. Moreover, we have tested beta-endorphin-like immunoreactivity (beta-END-LI) concentrations in culture media under control conditions and following treatments of theca cells with LH, PRL, progesterone (P4), oestradiol (E2) or testosterone (T). FK 33-824 and NAL significantly increased P4 release by theca cells and inhibited stimulatory effect of LH on this steroid output. PRL-induced P4 secretion from the cells was blunted only by FK 33-824. Secretion of androstenedione (A4) and T was essentially elevated in the presence of FK 33-824 and this potentiation of both androgen release was completely abolished by PRL. NAL blocked stimulatory effect of the opioid agonist only in case of T. Secretion of oestradiol and oestrone was completely free from the influence of both the opioid agonist and antagonist. Pig theca cells were able to produce beta-END-LI but none of tested hormones (LH, PRL, P4, E2 and T alone or in combination) significantly affected this production. In conclusion, these data indicate that porcine theca cells may produce beta-END-LI and change their steroidogenesis in response to opioid peptides.  相似文献   
24.
The clinical form of the protothecosis in animals is most commonly observed in countries with a warm and moist climate, only a few reports describing cases of this infection in cooler areas of the word exist. In the case of large bowel infection in dogs, organisms colonise the lamina propria and submucosa causing severe necrotizing ulcerative or haemorrhagic enterocolitis. In this report the intestinal form of protothecosis in 1.5-year-old, male, mongrel dog with chronic hemorrhagic diarrhoea is described. History revealed that the dog spent some time in the countryside and afterwards diarrhoea with fresh blood appeared. The results of morphological and biochemical blood analysis were normal and stool examination did not reveal the presence of parasites. Treatment with anti-inflammatory doses of prednisone, metronidazole and enrofloxacin followed by sulphasalazine resulted in a short period of improvement, but was followed by deep deterioration of animal status. Because of the relapse diagnostic laparotomy was performed and tissue samples of the colon and jejunum were obtained for histopathology. On the basis of the clinical signs, exploratory laparotomy findings and histopathology the diagnosis of canine intestinal prototecosis was made and medical treatment was recommended.  相似文献   
25.
The aim of the study was to examine potential interactions among IGF-I and proinflammatory cytokines, TNF-alpha and IFN-gamma, in the regulation of local IGF-I bioavailability and cellular proteins mediating myogenic signals. We investigated levels of IGFBP-4, -5, -6, protein kinase Czeta (PKC zeta), p38 and extracellular signal-regulated kinase (ERK1/2) in differentiating mouse C2C12 myoblasts. IGF-I significantly stimulated expression of IGFBP-5. TNF-alpha and IFN-gamma attenuated the expression of IGFBP-4 and -6 under basal conditions and in the presence of IGF-I, and inhibited IGF-I-induced IGFBP-5 expression during 5-day myogenesis. TNF-alpha and IFN-gamma markedly attenuated p38 expression in the presence of IGF-I on the 5th day of myogenesis. When combined with IGF-I the cytokines exerted opposite effects on the PKC zeta level, i.e. TNF-alpha caused an increase, whereas IFN-gamma reduced the cellular content of this kinase. Exposition of C2C12 myoblasts to IGF-I or cytokines led to the stimulation of ERK1/2 phosphorylation; however, both TNF-alpha and IFN-gamma exerted an inhibitory effect on the activation of ERK1/2 in myoblasts cultured in the presence of IGF-I. We concluded as follows: i) TNF-alpha and IFN-gamma present in the extracellular environment of differentiating C2C12 myoblasts can alter the local bioavailability of IGF-I by inhibiting the expression of IGFBP-4, -5, and -6, ii) the decrease in p38 expression and ERK1/2 phosphorylation in C2C12 myoblasts exposed to cytokines can lead to disturbances in IGF-I-regulated myogenesis.  相似文献   
26.
The aim of the study was to investigate the effects of supplementation of a microencapsulated blend of tributyrin and lactitol (TL) to a standard European (EU) diet without antibiotic growth promoters on intestinal metabolism and mucosa development of weaned piglets and to compare it with a standard US diet containing animal proteins, zinc oxide, copper sulfate, and carbadox. Ninety piglets weaned at 21 d were divided into 3 dietary groups consisting of 5 replicates each: 1) US diet supplemented with 55 mg/kg of carbadox, and 2.5% each of plasma proteins and spray-dried blood cells in the first phase, 3,055 mg/kg of Zn in the first and second phases, and 180 mg/kg of Cu in the third phase; 2) EU diet based on vegetable proteins and no antibiotics; and 3) the same EU diet supplemented with 3,000 mg/kg of microencapsulated TL. The study was divided into 3 phases: 0 to 7, 8 to 21, and 22 to 35 d. On d 7, 21, and 35, animals were weighed, and feed consumption and efficiency were determined. On d 14 and 35, one pig per pen was killed, and the intestinal contents and mucosa from the proximal, middle, distal jejunum and the ileum were sampled. Intestinal wall sections were fixed for histological analysis, and intestinal content was used for VFA, ammonia, and polyamine analysis. Throughout the study (d 0 to 35), the US diet had greater ADG and ADFI than the EU diet (P < 0.05). The EU diet supplemented with TL tended to have 11% greater ADG (P = 0.17). Feeding the EU diet caused a reduction in proximal and middle jejunum villi length by 10% (P < 0.05) and an increase in crypt size in proximal jejunum (P < 0.05) compared with the US diet, probably due to an increased rate of cell loss and crypt cell production. The TL supplementation resulted in longer villi along the jejunum and less deep crypts in the proximal jejunum (+15.9 and -8.9%, respectively; P < 0.05) than the unsupplemented EU diet. The TL diet increased the concentrations of cadaverine and putrescine in the small intestine (P < 0.05) and seemed to increase cadaverine, histamine, putrescine, and spermine in the large intestine by 1.5- to 10-fold compared with the US or EU diet. In conclusion, although the US diet had a greater effect on growth performance and mucosal trophic status than the EU diets, the supplementation with slowly released TL seemed to be an effective tool to partially overcome the adverse effects of vegetable protein diets.  相似文献   
27.
1.?The effect of dietary pea and addition of organic acid blend (OA) or probiotic (Pro) on performance and caecal microbial ecology of broiler chickens was studied.

2.?A growth trial was conducted with 160 Ross 308 female broilers from d 1 to 35 of age. There were 8 treatment groups based on either control (S) or white pea (P). Both S and P were supplemented with OA (Galliacid – fumaric acid, calcium formate, calcium propionate and potassium sorbate coated with plant triglycerides, Vetagro) and or with Pro (LABYuc-Probio – lactic acid bacteria, Saccharomyces cerevisiae and Yucca schidigeri extract, Mifarmex GmbH).

3.?Inclusion of peas in the diet increased feed intake and decreased gain:feed ratio in comparison to the control diet. Neither probiotic nor OA supplementations affected broiler performance.

4.?The caecal microbiota was characterised in 37-d-old birds by fluorescent in situ hybridisation (FISH) and terminal-restriction fragment length polymorphism (T-RFLP). Total bacterial counts in caecal contents were slightly higher for birds fed the pea diets, but were not affected by OA or Pro supplements.

5.?Neither pea nor Pro affected the Lactobacillus/Enterococcus and Streptococcus/Lactococcus counts in caecal contents, whereas OA supplementation slightly increased the Lactobacillus/Enterococcus counts. The composition of the Lactobacillus/Enterococcus population was altered by inclusion of peas as revealed by the T-RFLP patterns.

6.?The DNA fingerprint further suggested that the caecal microbiota was dominated by the lactic acid bacterium Streptococcus alactolyticus.

7.?In ileal contents, the concentration of short-chain fatty acids (SCFA) was decreased only by Pro supplementation. In caecal contents, the SCFA concentration was higher for birds fed on the pea diets, and increased significantly with Pro supplementation

8.?In conclusion, the results indicate that the use of pea and probiotics in broiler feed may stimulate the caecal commensal microbiota (growth and/or activity) to some extent and hence prevent establishment of pathogenic and zoonotic enterobacteria in these segments of the gut.  相似文献   

28.
Infrared thermography is a non-invasive technique which allows to distinguish between pregnant and non-pregnant animals. Detecting accurate body surface temperatures can be challenging due to external factors altering thermograph measurements. This study aimed to determine the associations between the ambient temperature, the hair coat features and the temperatures of mares' abdomens. It compared pregnant and non-pregnant mares throughout 11 months. The research was carried out on 40 Konik Polski mares, which were divided into pregnant and non-pregnant groups. The temperature (Tmax, maximal; Taver, average; Tmin, minimal) of the mares' abdomen was evaluated in two regions of interest: the whole area of the lateral surface of the mares' abdomen (Px1) and the flank area of the lateral surface of mares' abdomen (Px2). During the increasing period, the slopes in the linear regression equation did not differ significantly for ambient (Tamb) and surface temperatures in both groups. In the decreasing period, the slopes did not differ significantly for Tamb and Tmax in the non-pregnant group. They also did not differ for Tamb and Taver in Px1 and Tamb and Tmin in Px1 in both pregnant and non-pregnant groups respectively. Other slopes varied significantly (p < .001). There was no evidence of parallel changes in hair coat features and measured temperatures. The flank area appears more suitable for thermal imaging in pregnant mares due to the seasonal fluctuations in hair coat lengths.  相似文献   
29.
Birds obtained by embryo engineering are used to study embryo development and to produce transgenic birds. As this method of producing birds still generate strong emotions of the public opinion head ornaments, testes and semen characteristics of sex chimera roosters were examined to check whether they differ from chickens obtained by non‐manipulated methods. Measurements of head ornaments, testes and semen were correlated with each other. Semen quality factor (SQF) was calculated, as well as the level of fluctuating asymmetry (FA) of bilateral traits (wattles and testes). Positive correlation was found for comb width and wattle length and comb thickness and sperm concentration. Semen characteristics and FA did not exceed the level encounter in other chicken lines. Results obtained indicate that germline chimeras are similar in appearance of secondary sexual traits, and semen and testes characteristics to chickens produced in non‐manipulated way.  相似文献   
30.
The experimental materials comprised 44 hybrid [female (Polish Large White x Polish Landrace) x male Duroc] growing-finishing pigs. The animals were randomly divided into two groups: 24 pigs were slaughtered immediately after transport and 20 pigs were slaughtered after a 24-hour rest period in the lairage. The meat content of pork carcasses, carcass dressing percentage, the proximate chemical composition, physicochemical and sensory properties of meat and shear force values were determined. Serum creatine kinase activity and cortisol levels were determined in blood samples collected before transport and during carcass bleeding. Pigs slaughtered immediately after transport, compared with those slaughtered after a 24-hour rest period, were characterized by a higher meat content of the carcass and a higher carcass dressing percentage. Pre-slaughter handling had no effect on pork quality. The incidence of normal-quality meat, partially PSE (pale, soft, exudative) meat and PSE meat was similar in both groups. Chemical analysis showed that the content of dry matter, total protein, fat and minerals in meat was comparable in both groups. As regards the functional properties of the pork, samples from the carcasses of pigs that had rested before slaughter had a higher contribution of the red color component. Meat from pigs slaughtered immediately after transport had more desirable sensory properties. Pre-slaughter resting had a significant effect on those analyzed physiological parameters which were found to be good indicators of pre-slaughter stress. Serum creatine kinase activity and cortisol levels were higher in blood samples collected after transport (during carcass bleeding) than in samples collected before transport, pointing to a strong stress response of animals to pre-slaughter treatment. The decrease in serum cortisol levels in blood samples collected during bleeding from the carcasses of pigs slaughtered after a 24-hour rest period, compared with samples collected from animals slaughtered immediately after transport, suggests that rest before slaughter alleviated stress induced by pre-slaughter handling operations.  相似文献   
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