Differential expression of peroxisome proliferator-activated receptors alpha and gamma gene in various chicken tissues

The peroxisome proliferator-activated receptors (PPARs) are the members of superfamily of nuclear hormone receptors. A great number of studies in rodent and human have shown that PPARs were involved in the lipids metabolism. The goal of the current study was to investigate the expression pattern of PPAR genes in various tissues of chicken. The tissue samples (heart, liver, spleen, lung, kidney, stomach, intestine, brain, breast muscle and adipose) were collected from six Arber Acres broilers (8 weeks old, male and female birds are half and half). Semi-quantitative RT-PCR and Northern blot were used to characterize the expression of PPAR-alpha and PPAR-gamma genes in the above tissues. By semi-quantitative RT-PCR, the results showed the expression level of PPAR-alpha gene was higher in brain, lung, kidney, heart and intestine, medium in stomach, liver and adipose than in spleen, and it did not express in breast muscle. The expression level of PPAR-gamma gene was higher in adipose, medium in brain and kidney than in spleen, heart, lung, stomach and intestine, but it did not express in liver and breast muscle. Northern blot results showed that PPAR-alpha gene expressed in heart, liver, kidney and stomach, and the intensity of hybridization signal was the stronger in liver and kidney than in other tissues, however, PPAR-gamma gene only expressed in adipose and kidney tissues. The results of this study showed the profile of PPAR gene expression in the chicken was similar to that in rodent, human and pig. However the expression profile of chicken also have its own specific trait, i.e. compared with mammals, PPAR-alpha gene can not be detected in skeletal muscle and PPAR-gamma gene can be stronger expressed in kidney tissues. This work will provide some basic data for the PPAR genes expression and lipids metabolism of birds.     

Trichuris suis excretory secretory products (ESP) elicit interleukin-6 (IL-6) and IL-10 secretion from intestinal epithelial cells (IPEC-1)

Immune responses to gastrointestinal helminth infections have received increasing attention due to similarities to allergen-induced responses. In fact, the whipworm parasite of swine, Trichuris suis, has been used in beginning clinical trials as an antidote to inflammatory bowel disease. This strategy was based on this similarity and the recognition that other worms have been documented to induce anti-inflammatory responses in the host. In an effort to understand the basis for this response, we hypothesized that the proteins and peptides secreted by T. suis stimulate local intestinal epithelial cells to produce anti-inflammatory cytokines. To test this hypothesis in a correlate system of the natural swine host, T. suis excretory secretory products (ESP) were used to treat both differentiated and undifferentiated intestinal pig epithelial cells (IPEC-1) in vitro as a model for the effect on villus tip and crypt epithelial cells in the vicinity of the worms. IPEC-1 were exposed to low-level doses (0.3mg/ml) of T. suis ESP, and IL-4, IL-6 and IL-10 cytokine responses were measured by an enzyme-linked immunosorbant assay (ELISA). IL-6 was the predominant cytokine produced, accompanied by moderate IL-10 secretion from both differentiated and undifferentiated cells. As expected, IL-4 was not produced by IPEC-1. Additionally, IL-6 and IL-10 cytokines were produced within 24h, suggesting that these two cytokines form part of the primary host response to T. suis infections. These data suggest that T. suis ESP could enhance host immune responses and modulation through the induction of enteric IL-6 and IL-10.     

Evaluation of tulathromycin for the treatment of pneumonia following experimental infection of swine with Mycoplasma hyopneumoniae

Tulathromycin was evaluated in the treatment of pneumonia in weaned pigs inoculated intranasally with Mycoplasma hyopneumoniae. Five days postchallenge, the pigs were randomized to treatment with a single IM administration of saline, a single IM administration of tulathromycin (2.5 mg/kg; day 0), or three IM administrations of enrofloxacin (5.0 mg/kg; days 0, 1, 2). Pigs were necropsied on day 12 or 13. Unchallenged controls remained healthy with no lung pathology. Compared with saline, coughing, mean lung lesion score, and proportional lung weight were significantly reduced and weight gain was significantly greater for tulathromycin-treated pigs (P < .05). Compared with enrofloxacin, there were no significant differences in proportional lung weight or weight gains, but coughing and lung lesion scores were greater for tulathromycin-treated pigs (P < .05). Tulathromycin was effective in the treatment of pneumonia following experimental infection with M. hyopneumoniae.     

Mixed models applied to the study of variation of grower-finisher mortality and culling rates of a large swine production system

Large scale production systems for swine are frequently organized in a hierarchical structure. Consequently, important production parameters, such as mortality and culling, can be analyzed at different levels. The major aims of this study were to assess variance components (VC) of mortality and culling rates attributed to sites and to barns within a site, and subsequently to investigate the impact of average entry weight, days on feed (length of the production turn), and season on the magnitude of the VC. Then, data from a large farm with 3 sites were collected during 5 y. In total, 1720040 pigs distributed in 1502 all-in/all-out grower-finisher groups were included. Linear mixed models were fitted for mortality and culling rates. The barn was modeled as the residual component (barn-to-barn variations) with production turn and site nested within production turn as random intercept variance components. Barn-to-barn pig group variation was the largest VC for mortality (63.08%), when no predictors were included in the models. Predictors, such as pigs placed on quarters 2 and 3, low average entry weight, and shorter production turn length, were associated together with higher mortality. The explained proportion of variance due to these predictors was about 12.05% and the VC for barn, site, and production turn were 67.6%, 17.6%, and 14.8%, respectively. Barn-to-barn variation was also the largest VC for culling rate (46.2%), but the same predictor mentioned above explained only about 1.4% of the variation. The VC for barn, site, and production turn were 46.8%, 21.3%, and 31.8%, respectively. Since the variability among barns far exceeded the variability among sites, the barn should be used as experimental unit in studies with grower-finisher mortality, culling rate, or both, as outcome variables.     

Efficacy of two dichlorvos formulations against larval and adult Hyostrongylus rubidus in swine.

Coated (V-13) and uncoated (V-22) formulations of dichlorvos were used to treat experimentally established Hyostrongylus rubidus infections of pigs at intervals after exposure to infective larvae. Both dichlorvos formulations were efficacious against the adult stomach worm H rubidus, but showed little or no activity against 5- or 15-day-old worms. Neither formulation was as effective against H rubidus in sows as in barrows and gilts.     

Cardiopulmonary effects of fentanyl-droperidol, nitrous oxide, and atropine sulfate in dogs.

The cardiopulmonary effects of droperidol-fentanyl, nitrous oxide, and atropine were evaluated in 12 adult male Beagle dogs. All dogs were surgically instrumented with a cardiac output thermistor and arterial and venous catheters and were prepared with a chronic tracheostomy. Each dog was used as its own control, and data obtained when dogs were nonanesthetized and nonmedicated were compared with data recorded after the test drugs were administered. The dogs were randomly allotted to 3 groups of 4 dogs each. Group I dogs were given droperidol-fentanyl alone intravenously (IV); group II dogs were given droperidol-fentanyl IV with 67% nitrous oxide; and group III dogs were given atropine sulfate intramuscularly followed by droperidol-fentanyl IV with 67% nitrous oxide. Minute volume was decreased in the 3 groups of dogs for 3 to 5 minutes after droperidol-fentanyl was injected. This resulted in respiratory and metabolic acidosis in all dogs, as indicated by increased arterial carbon dioxide tension, decreased pH, and increased base deficit. In addition, droperidol-fentanyl given alone caused a decrease in systolic pressure and a slight decrease in heart rate. Group 1 dogs were sensitive to auditory stimulation. Cardiovascular changes were not seen when nitrous oxide was added; however, analgesia and muscle relaxation were improved. Premedication with atropine sulfate resulted in increased cardiac output, heart rate, and diastolic pressure, and subsequent administration of droperidol-fentanyl with nitrous oxide caused a transient increase in mean arterial and systolic pressure. This last anesthetic regimen, along with assisted or controlled respiration, seems to provide an excellent anesthetic state with minimal cardiopulmonary depression.