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51.
Nine pigs were fed crystalline ochratoxin A in their feed at a concentration of about 1 mg/kg. Three pigs and their controls were killed after 3 months and 6 pigs and controls were killed after 2 years. A decrease of the ratio TmPAH/CIn, increased urinary glucose excretion and decreased ability to concentrate urine, occurred within a few weeks and aggravated slightly during the 2-year period. Changes in renal structure, characterized by degeneration and atrophy of proximal tubules, interstitial fibrosis and hyalinization of glomeruli, were progressive during time of exposure, but terminal renal failure was not reached. The kidney, liver, muscular and adipose tissue contained 3 to 27 microgram ochratoxin A/kg after 3 months of exposure. No further accumulation of ochratoxin A residue was found after 2 years of exposure.  相似文献   
52.
The occurrence of Mycoplasma hyosynoviae at different locations of the upper respiratory tract and tonsils of pigs was investigated in herds with problems of arthritis apparently caused by this microorganism. The isolation of M. hyosynoviae was facilitated by the use of a medium selectively suppressing the growth of Mycoplasma hyorhinis. M. hyosynoviae was cultured from 106 of 178 tonsils of slaughterhouse pigs from 8 herds but could not be isolated from the mucosa of the nasal cavity or the oral-pharyngeal area of 100 living, 10-20 weeks old pigs in 5 of the herds. The value of the selective principles in the medium appears from the circumstance that 86 of the 106 isolates were obtained despite the presence of M. hyorhinis. It is concluded that the tonsil is a reservoir for M. hyosynoviae and is probably the location of choice for an easy demonstration of the presence of this mycoplasma in a pig herd.  相似文献   
53.
Liu M  Hansen PE  Lin X 《Marine drugs》2011,9(7):1273-1292
Marine algae contain various bromophenols that have been shown to possess a variety of biological activities, including antioxidant, antimicrobial, anticancer, anti-diabetic, and anti-thrombotic effects. Here, we briefly review the recent progress of these marine algal biomaterials, with respect to structure, bioactivities, and their potential application as pharmaceuticals.  相似文献   
54.

The ability of lactating mink dams to control glucose homoeostasis, when fed diets containing different ratios of metabolizable energy (ME) from protein, fat and carbohydrates, was studied by measuring plasma concentrations of glucose, insulin, glucagon, urea and free fatty acids (FFA), in the fasted and absorptive state 4 weeks postpartum, in two consecutive years. A total of 36 yearling female mink, fitted with jugular vein catheters and raising litters of six or seven kits, was fed ad libitum lactation diets with different amounts of ME derived from protein, fat and carbohydrates (year 1:61:37:2, 46:37:17 and 31:37:32; year 2:61:38:1, 47:52:1 and 33:66:1). After 3 h fasting the dams were fed 210 kJ ME of the experimental diets. Blood samples were drawn 10 and 5 min before feeding and 30, 60, 90, 120, 150 and 180 min postprandially. The glucose concentration was increased 30 to 150 min postprandially in dams fed the carbohydrate-containing diets (46:37:17 and 31:37:32), whereas the glucose concentration showed no postprandial response in dams fed the carbohydrate-free diets (61:38:1, 47:52:1 and 33:66:1). Plasma insulin concentrations were increased 30 to 120 min postprandially in all dams, irrespective of dietary treatment. Plasma concentrations of glucagon were higher ( P <0.005) in dams fed the low-protein diets (31:37:32 and 33:66:1) than in dams fed the high-protein diets (61:37:2 and 61:38:1). Postprandially, the glucagon : insulin ratios decreased in dams fed the carbohydrate-containing diets, whereas the glucagon:insulin ratios tended to increase in dams fed the carbohydrate-free diets. Plasma concentrations of urea were significantly higher in dams fed the high-protein diets. Plasma concentrations of FFA, measured in the second experiment (year 2) only, showed increased concentrations postprandially, the responses being significant in dams fed the 33:66:1 and 61:38:1 diets. In conclusion, the mink is able to regulate the concentrations of blood constituents involved in maintaining glucose homoeostasis, and thereby to adapt to a wide range of dietary protein and carbohydrate supply.  相似文献   
55.
Abstract

Alternative selection strategies in the bull dam path were investigated to reduce the magnitude of bias. The study's objective was to examine the effect of alternative strategies under the assumption of particular biases. Bias in the evaluation of bull dam estimated breeding values (EBVs) causes an estimated reduction of 32% in their genetic superiority, compared with the theoretical potential. Biased evaluations caused selection of too many bull dams from later lactations. Two alternative strategies were developed to account for existing bias. Results suggested that the influence of bias could be reduced. The estimated improvement in selection response was 11–13% higher than current practice. Problems with biased EBVs in conventional breeding schemes are discussed and a method to counteract bias from future breeding schemes is presented.  相似文献   
56.
Abstract

Plasma growth hormone (GH) secretory profiles of 8-week-old male and female broiler chickens selected for high body weight at 42 days of age (GL line) or for improved food efficiency between 18 and 39 days of age (FCR line) were compared. A pulsatile GH secretory pattern was still present for all the 8-week-old chickens examined. Overall mean GH levels, and to a lesser extent GH baseline and GH amplitude values, were higher for FCR chickens compared with GL chickens. Mean GH concentrations, baseline and amplitudes were slightly, but not significantly, superior in males. Length and frequency of pulses were not influenced by line or sex. In view of the current knowledge on age- and sex-related changes in pulsatile GH secretion, it is argued that the line and sex differences would have been more pronounced in younger chickens. Based on this, the hypothesis that the amplitude of the pulsatile GH release is related to protein conversion efficiency and protein deposition rather than to average body weight gain is corroborated.  相似文献   
57.

Background

Avian influenza virus (AIV) subtypes H5 and H7 attracts particular attention because of the risk of their potential pathogenicity in poultry. The haemagglutination inhibition (HI) test is widely used as subtype specific test for serological diagnostics despite the laborious nature of this method. However, enzyme-linked immunosorbent assays (ELISAs) are being explored as an alternative test method.H5 and H7 specific monoclonal antibodies were experimentally raised and used in the development of inhibition ELISAs for detection of serological response specifically directed against AIV subtypes H5 and H7. The ELISAs were evaluated with polyclonal chicken anti-AIV antibodies against AIV subtypes: H1N2, H5N2, H5N7, H7N1, H7N7, H9N9, H10N4 and H16N3.

Results

Both the H5 and H7 ELISA proved to have a high sensitivity and specificity and the ELISAs detected H5 and H7 antibodies earlier during experimental infection than the HI test did. The reproducibility of the ELISA’s performed at different times was high with Pearson correlation coefficients of 0.96-0.98.

Conclusions

The ELISAs are a potential alternative to the HI test for screening of large amounts of avian sera, although only experimental sera were tested in this study.  相似文献   
58.
Monitoring of the body temperature in animals kept under intensive production conditions is desirable for a number of reasons: oestrus detection, disease monitoring and stress indication in addition to more specific needs, such as the selection of breeding pigs resistant to malignant hyperthermia and for various research purposes.  相似文献   
59.
Pericarditis, acute or subacute, is found at post mortem meat inspection of baconers in about 0.02 to 0.04% of slaughtered pigs in Denmark. The pathological findings are usually restricted to the pericardial sac. The pericardial sac is filled with a fibrinous exudate, which may be blood stained. In some cases massive granulation tissue formation is seen underlying the fibrinous exudate. Other constantly occurring, but less aggravating lesions, are chronic catarrhal bronchopneumonia and increased volume of serosanguinous synovial fluid in the large joints of the limbs. Lesions usually seen as sequelae to septicaemia have not been observed. The lesions seem to be part of a pathological entity which may be involved in the pathogenesis of fibrinous pericarditis in baconers.  相似文献   
60.
The occurrence of Mycoplasma hyosynoviae in synovial fluid of baconers with chronic arthritis was studied at an abattoir. Cultural examination of synovial fluid samples from diseased tarsal joints of 50 animals from 42 herds yielded M. hyosynoviae in 10 cases from 8 herds. Streptococci were found in 6 cases from 6 other herds. M. hyosynoviae antigen was found in 1 of 47 of the samples, and antibody to the mycoplasma was found in 14 of 40 of the samples by ELISA test. The presence of M. hyosynoviae in a joint was usually accompanied by the corresponding antibody. In joints with streptococcal infection antibody to M. hyosynoviae could not be found.  相似文献   
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