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991.
In this study, we injected morphine sulfate IP into rainbow trout and measured the concentration of morphine and all potential metabolites in plasma using LC-MS/MS at a series of times after the injection. The pharmacokinetics of morphine were similar to those previously reported for seawater-acclimated rainbow trout, i.e. they were about one order of magnitude slower than in similarly sized mammals. The only metabolite of morphine present in the plasma was morphine-3-β- d -glucuronide (M3G); morphine-6-β- d -glucuronide (M6G) was not detected. M3G gradually increased after the morphine injection, peaked about 2 days later, then gradually decreased. In mammals, M3G plasma levels exceed morphine levels extremely rapidly, i.e. in less than an hour, regardless of dose, route of administration, or species. In trout, it took 2 days for M3G levels to exceed morphine levels. This is the first study of the metabolites of morphine in any ectotherm. We conclude that trout can metabolize morphine, but at a rate much slower than in mammals.  相似文献   
992.
Adipose tissue gene expression in obese dogs after weight loss   总被引:1,自引:0,他引:1  
Body weight (BW) mainly depends on a balance between fat storage (lipogenesis) and fat mobilization (lipolysis) in adipocytes. BW changes play a role in insulin resistance (IR), the inability of insulin target tissue to respond to physiological levels of insulin. This results in inhibition of lipogenesis and stimulation of lipolysis. Weight gain leads to IR whereas, weight loss improves insulin sensitivity (IS). The aim of this study was to evaluate the effect of weight loss and recovery of IS on the expression of genes involved in lipogenesis and lipolysis in weight losing dogs. Gene expression was studied in both subcutaneous and visceral adipose tissue. Obese dogs received a hypoenergetic low fat high protein diet (0.6 x NRC recommendation). Before and after weight loss, IS was assessed using the euglycaemic hyperinsulinaemic clamp. Gene expression of IRS-2, SREBP, intracellular insulin effectors, ACC, FAS, FABP, ADRP, PEPCK, lipogenesis key proteins, perilipin and HSL, lipolysis key proteins were quantified using real-time RT-PCR in subcutaneous and visceral fat. BW decreased from 15.2 +/- 0.5 to 11.4 +/- 0.4 kg (p < 0.05) over 78 +/- 8 days. When obese, dogs were insulin resistant. After weight loss, IS was improved. In the subcutaneous adipose tissue, the expression of only the IRS-2 was increased. In the visceral adipose tissue, the expression of the genes involved in the lipogenesis was decreased whereas one of the genes implied in the lipolysis did not change. The expression profile of genes involved in lipid metabolism, as measured after weight loss, is indicative for a lower lipogenesis after weight loss than in obese dogs. Our results also confirm dramatic differences in the lipid metabolism of visceral and subcutaneous fat. They should be completed by comparing gene expression during weight losing and normal weight steady state.  相似文献   
993.
994.
The Aerococcus viridans isolates from bovine mastitis in Slovakia were isolated and characterized by classical microbiological and biochemical, and molecular techniques including IGS-PCR and rep-PCR, ARDRA and 16S rDNA gene sequencing. The substantial variability of antibiotic resistance patterns was observed. The majority of strains were resistant to beta-lactam antibiotics, the resistance to tetracycline was observed in 3 tested strains, resistance to lincomycin was found in 4 strains and practically all tested strains were sensitive to neomycin and ciprofloxacin. While variable at a phenotypic level, no significant genetic variability among A. viridans isolates was detected by molecular DNA based methods. The data obtained suggest that a few A. viridans strains spread among cow's population in Slovak farms.  相似文献   
995.
A cohort study was carried out on 112 breeding pig farms in England to investigate the impact of type of farrowing accommodation on preweaning mortality in piglets. Four types of farrowing accommodation were studied; farrowing crates, indoor loose pens, crate/loose systems (where the sow was restrained in a crate during birth and the first days of lactation before being moved to a loose pen) and outdoor farrowing in arcs in paddocks. Four estimates of preweaning mortality were collected: an oral estimate from the farmer before the visit, an estimate from the 6-month rolling average from computer records, records from 20 litters observed when the farm was visited and prospective records collected from 20 farrowings after the visit. These four estimates were significantly correlated. The prospective records also included a farmer reported date and cause of death. From the prospective data there were 25,031 piglets from 2143 litters from 112 farms, 6.5% of piglets were stillborn while live born preweaning mortality was 12%. Mixed effect discrete time survival, binomial and competing risk, models were used to investigate the association between preweaning mortality and farrowing accommodation, controlling for sow parity, litter size and number of piglets stillborn and fostered. There was a reduced risk of stillbirths in outdoor farrowing systems compared with crated systems. Farmers reported that crushing of healthy piglets was the most frequent cause of death accounting for 55% of live born preweaning mortality. There was no significant difference in mortality in live born piglets by farrowing system. There was a significantly higher risk of farmer reported crushing of healthy live born piglets in outdoor arcs compared with piglets reared with sows in farrowing crates and a significantly reduced risk of death from causes other than crushing in piglets reared outdoors or in crate/loose systems compared with piglets reared in crated systems. We conclude that, in the farms in this study, farrowing crates reduced the risk of preweaning live born mortality attributable to crushing but piglets in this system were at increased risk of death from other causes. Consequently crates had no significant effect on overall preweaning mortality percentage. In all four commercial production systems; outdoor, farrowing crates, crate/loose farrowing systems and indoor loose housed systems, there were similar levels of mortality.  相似文献   
996.
Canine elbow dysplasia encompasses four developmental diseases: ununited anconeal process, osteochondrosis of the medial part of the humeral condyle, fragmented medial coronoid process (FCP), and incongruity of the elbow joint. Four radiographic views per joint were used to evaluate 2693 Labrador Retrievers (LRs), 1213 Golden Retrievers (GRs), and 974 Bernese Mountain Dogs (BMDs) for the presence of elbow dysplasia between 2002 and 2009 in the Netherlands. The views were also graded for signs of osteoarthritis and sclerosis. FCP was diagnosed most frequently in LRs, GRs and BMDs, with an incidence of 6%, 5%, and 15%, and a heritability of 0.17, 0.24, and 0.06, respectively. Heritabilities were estimated using a sire model and all available ancestors. Sclerosis at the base of the medial coronoid process was the radiographic sign most strongly correlated with FCP (r=0.95, 0.92, and 0.95 in LRs, GRs and BMDs, respectively). The sex of the dog was significantly correlated with the presence of osteoarthritis in LRs, but not in GRs and BMDs. Male LRs were 1.7-fold more frequently, but not more severely, affected by osteoarthritis than female dogs. Age at radiographic examination was significantly associated with osteoarthritis in all three breeds. The heritability estimates in Retrievers were high enough to warrant including FCP findings in the breeding policy, but until the biomechanical and genetic background of elbow dysplasia are better understood, correct phenotyping with a sensitive technique is essential.  相似文献   
997.
Babesiosis is an emerging tick-borne disease of animals and humans caused by intraerythrocytic protozoa of the genera Babesia and Theileria. In France canine babesiosis has a high prevalence with Babesia canis thought to be the main aetiological agent of the disease. Babesia vogeli has already been reported to occur in Europe and in other countries around the Mediterranean Sea. The tick Rhipicephalus sanguineus, the main known vector of B. vogeli, occurs in southern France. However, only one case of a B. vogeli infected dog has been reported to date in France. To gain further insight into the prevalence of Babesia and Theileria infections in dogs and ticks of the R. sanguineus complex, a study was conducted in a veterinary practice in the south of France from January to September 2010. Twelve bloods from dogs and 36 R. sanguineus ticks were analyzed using PCR and sequencing. For the analysis of ticks, a new primer was designed to specifically amplify the B. vogeli 18S rRNA gene. Four dogs (33.3%) and 8 ticks (22.2%) were found to be infected with B. vogeli. This approach has thus revealed for the first time a cluster of cases of canine babesiosis caused by B. vogeli in France and highlights the need to systematically screen for pathogens potentially responsible for canine babesiosis at the species level using suitable molecular tools.  相似文献   
998.
Newcastle disease (ND) is one of the most important diseases of poultry, and may cause devastating losses in the poultry industry worldwide. Its causative agent is Newcastle disease virus (NDV), also known as avian paramyxovirus type 1. Many countries maintain a stringent vaccination policy against ND, but there are indications that ND outbreaks can still occur despite intensive vaccination. It has been argued that this may be due to antigenic divergence between the vaccine strains and circulating field strains. Here we present the complete genome sequence of a highly virulent genotype VII virus (NL/93) obtained from vaccinated poultry during an outbreak of ND in the Netherlands in 1992-1993. Using this strain, we investigated whether the identified genetic evolution of NDV is accompanied by antigenic evolution. In this study we show that a live vaccine that is antigenically adapted to match the genotype VII NL/93 outbreak strain does not provide increased protection compared to a classic genotype II live vaccine. When challenged with the NL/93 strain, chickens vaccinated with a classic vaccine were completely protected against clinical disease and mortality and virus shedding was significantly reduced, even with a supposedly suboptimal vaccine dose. These results suggest that it is not antigenic variation but rather poor flock immunity due to inadequate vaccination practices that may be responsible for outbreaks and spreading of virulent NDV field strains.  相似文献   
999.
The objectives of this study were to characterize the glycemic and insulinemic responses of Thoroughbred broodmares fed late spring pasture only or a mixture of pasture and a high starch or low starch feed and to test hypotheses about differences in the glycemic and insulinemic effects of these dietary regimes. A group of 15 mares were divided into three treatment groups; pasture and high starch feed (PHS), pasture and low starch feed (PLS), and pasture only (PO) and maintained in these groups for 4.5 months prior to this study. These groups were maintained on a single pasture that was temporarily divided into three sections. The study protocol was conducted over two days. On day 1 the mares were fed their respective treatments and on day 2 all mares were allowed access to pasture only. On both days plasma glucose and insulin were measured in samples taken over a 7.5 h period. Baseline measurements for glucose and insulin were not different between any of the treatment groups on either day (P > 0.05). The baseline insulin concentrations of these pasture-kept mares (26.7 ± 8.3 mIU/L) were high compared to those reported from stall-kept horses. Plasma glucose and insulin on day 1 were influenced by treatment group, sample time, and an interaction between treatment and time (P < 0.05). On day 2 there was no significant influence of treatment group (P > 0.05). Glucose and insulin rose to higher (P < 0.01) peak concentrations in the PHS group on day 1 when compared to the PLS and PO groups, with no difference (P > 0.05) detected between the PLS and PO groups. These results are reflected in greater areas under the concentration-time curves for glucose and insulin in the PHS group on day 1 (P < 0.05). On day 2 there were no differences in any of the glucose and insulin characteristics for any of the treatment groups (P > 0.05). These results indicate a clear difference in the glycemic and insulinemic effect of the PHS feed compared to the PLS and PO groups. Of further interest are the glucose and insulin characteristics of these pasture-kept mares that indicate a low insulin sensitivity and high insulin secretory response. This study provides further information on factors influencing glycemic and insulinemic responses in horses.  相似文献   
1000.
Two experiments were conducted to evaluate receiving-period performance, morbidity, and humoral immune response, as well as finishing performance and carcass characteristics of heifers fed different sources of supplemental Zn. In Exp. 1, 97 crossbred beef heifers (initial BW = 223.4 kg) were fed a 65% concentrate diet with no supplemental Zn (control) or 75 mg of supplemental Zn/kg of DM from Zn sulfate, Zn methionine, or Zn propionate. During a 35-d receiving period, heifers were monitored daily for signs of bovine respiratory disease. Serum samples were collected for Zn analysis on d 0, 14, and 28. After the receiving period, heifers were adapted to and fed a high-concentrate diet with no supplemental Zn for 42 d. Heifers were then assigned to finishing diet treatments, with the same concentrations and sources of supplemental Zn as during the receiving period and fed for an average of 168 d. Serum samples also were obtained on d 0 and 56 of the finishing period and at the end of the study. During the receiving period, control heifers had a greater (P < or = 0.05) BW and G:F on d 35 than heifers in the other treatments, but no differences were observed among treatments for morbidity or serum Zn concentrations (P > or = 0.50). For the finishing period, DMI and ADG did not differ among treatments; however, overall G:F tended (P = 0.06) to be less for control heifers than for heifers in the 3 supplemental Zn treatments. On d 56 of the finishing period, control heifers tended (P = 0.06) to have a lower serum Zn concentration than heifers in the 3 supplemental Zn treatments. In Exp. 2, 24 crossbred beef heifers (initial BW = 291.1 kg) were fed the same 4 treatments as in Exp. 1 for a 21-d period. The humoral immune response to treatments was determined by measuring specific antibody titers after s.c. injection of ovalbumin on d 0 and 14. Body weights and blood samples for serum Zn concentration and ovalbumin IgG titers were collected on d 0, 7, 14, and 21. Serum Zn concentration and specific ovalbumin IgG titers did not differ (P > 0.10) among the 4 treatments on any sampling day. Results from these 2 studies showed no major differences among the sources of supplemental Zn for receiving period morbidity, ADG, DMI, and humoral immune response of beef heifers; however, a lack of supplemental Zn during an extended finishing period tended to negatively affect G:F.  相似文献   
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