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991.
Sixty sows were individually penned in a thermoneutral (20 degrees C) or hyperthermal (32 degrees C) environment and fed a basal (corn-soybean meal), high-fiber (48.5% wheat bran) or high-fat (10.6% choice white grease) diet from d 100 of gestation through a 22-d lactation. The diets were determined to contain 3.28, 2.76 and 3.75 Mcal ME/kg, respectively. All pigs received 8.0 Mcal of ME and 17.5 g of lysine daily prior to parturition and were allowed to consume their respective diets ad libitum after parturition. Litter size was standardized at 9 to 10 pigs by d 2 postpartum. Milk yields were determined for five, 4-d periods from about d 2 through 22 of lactation via a D2O dilution technique. Daily milk yield and litter weight gain began to plateau, and the efficiency of utilizing milk DM and milk energy for gain was depressed (P less than .01), in the latter stages of the lactation. Heat exposure (32 degrees C) reduced (P less than .05) voluntary ME intake and milk energy yield of the sow and increased (P less than .05) the sow's weight loss during lactation. In the hot environment, increasing dietary energy concentration resulted in a linear (P less than .08) increase in milk fat content and milk energy yield over the duration of the 22-d lactation. In the latter stages of lactation, pigs consuming high-fat milk required more (P less than .09) milk and milk energy per unit of weight gain. In the warm environment, milk energy yield was increased by dietary fat or fiber additions in early lactation, but not in late lactation. These results indicate that the effects of thermal heat stress on sow milk energy yield and litter weight gain are aggravated by dietary fiber addition and minimized by dietary fat addition.  相似文献   
992.
The aim of the study was to evaluate the influence of low dose (LOEL - lowest observed effect level) of zearalenone (200 microg/kg b.w.), applied per os for 7 days (short-term intoxication), on sexual behavior, concentration of the examined xenobiotic and its metabolite and selected estrogens in sexually immature gilts: ovariohysterectomised (group D1) and intact (group D2) animals. Clinical signs of oestrus (reddening, oedema and hyperaemia of the vulva and serorhoea from the reproductive tract--lack of standing reflex) were obserwed in group D1 on day 6 and in group D2 on day 4 of the experiment. Laboratory analyses of blood plasma were carried out determine the presence of zearalenone and alpha-zearalenole. They revealed an increase in the level of alpha-zearalenol before the oestrus, decrease in total amount of both examined substances on day when the oestrus appeared and increase in the level of both examined xenobiotics in the post oestrus period together with the higher share of zearalenone. Medium concentrations of estrone and estradiol within the borders of method determination in the majority of periods examined. Higher levels of estrone (32.0 pg/ml) were found on day 4, in the group D2 and estradiol (6.5 pg/ml) on day 6 in the D2 group. The presents study revealed that zearalenone applied per os at LOEL dose causes the incidence of apparent sexual readiness (without standing reflex) in sexually immature gilts with the somatically immature reproductive system.  相似文献   
993.
Addition of pseudorabies virus (PrV)-specific polyclonal immunoglobulins to PrV-infected monocytes induces internalization of plasma membrane anchored viral glycoproteins. This process may interfere with antibody-dependent cell lysis and resembles the well-studied physiological endocytosis process. A confocal study was designed to investigate whether the major cellular components, involved in physiological endocytosis (clathrin, actin, dynein and microtubules), play a role in this virological internalization process. In order to visualize the interaction of endosomes, which contain the internalized viral glycoproteins, with clathrin, actin, dynein and microtubules, a double labeling of viral glycoproteins and different cellular proteins was performed. Porcine monocytes were inoculated with the PrV-strain 89V87 at a multiplicity of infection of 50 for 13h. After the addition of FITC-labeled porcine polyclonal PrV-specific antibodies, cells were fixed with para-formaldehyde at different time points and afterwards permeabilized. The different cellular components were visualized with monoclonal antibodies and a Texas Red-conjugate, with the exception of actin, which was stained with phalloidin-Texas Red. The cells were analyzed by confocal microscopy. A clear co-localization was observed between the viral glycoproteins and clathrin and dynein during the internalization process. The microtubules were in close contact with the internalized vesicles. For actin no co-localization could be observed. It can be stated that clathrin, dynein and microtubules, important components during physiological endocytosis, are also of importance during the antibody-induced internalization of viral glycoproteins.  相似文献   
994.
995.
OBJECTIVE: To develop a model for measuring rotary stability of the canine elbow joint and to evaluate the relative contribution of the anconeal process (AN), lateral collateral ligament (LCL), and medial collateral ligament (MCL). SAMPLE POPULATION: 18 forelimbs from 12 canine cadavers. PROCEDURE: Forelimbs were allocated to 3 experimental groups (6 forelimbs/group). Each intact forelimb was placed in extension at an angle of 135 degrees and cycled 50 times from -16 degrees (pronation) to +28 degrees (supination) in a continuous manner at 2.0 Hz. Cycling was repeated following sectioning of the structure of interest (group 1, AN; group 2, LCL; and group 3, MCL). Torque at -12 degrees (pronation) and +18 degrees (supination) was measured for each intact and experimentally sectioned limb. A Student t test was performed to compare torque values obtained from intact verses experimentally sectioned limbs and for comparison with established criteria for differentiation of primary (> or = 33%), secondary (10 to 33%), and tertiary rotational stabilizers (< 10%). RESULTS: In pronation, the AN was the only primary stabilizer (65%). For supination, the LCL was a primary stabilizer (48%), AN was a secondary stabilizer (24%), and MCL was a tertiary stabilizer (7%). CONCLUSIONS AND CLINICAL RELEVANCE: With the elbow joint in extension at an angle of 135 degrees, the AN is a primary rotational stabilizer in pronation, and the LCL is a primary stabilizer in supination. Disruption of the AN or LCL may affect rotary range of motion or compromise stability of the elbow joint in dogs.  相似文献   
996.
This article presents an overview of the clinical features of upper airway obstructive disorders. It includes more detailed discussions of certain common conditions such as brachycephalic airway syndrome, laryngeal paralysis, and upper airway obstruction due to trauma, foreign bodies, extraluminal masses, and tumours of the larynx and trachea.  相似文献   
997.
998.
The present study was undertaken to determine the influence of the peroneus tertius muscle on the loading regime of the tibia in the horse. Strain gauge rosettes were bonded to the cranial and caudal cortices of the left and right tibiae in six Shetland ponies. In vivo bone strain recordings were made before and after unilateral transection of the peroneus tertius muscle. Relatively large individual variations in response to transection were observed in both the experimental and the contralateral control limbs. The principal strain values on the cranial and caudal cortices increased during the second peak in the support phase by approximately 10 per cent; the angle between the larger principal strains and the long axis of the bone, measured proximal to the gauges, rotated approximately 4 degrees medially in experimental limbs, but did not change in the control limbs. It seems unlikely that the peroneus tertius muscle has a substantial influence on the loading regime of the tibia during normal walking.  相似文献   
999.
1000.
Nine monoclonal antibodies which reacted with equine immunoglobulin (Ig)M and not other equine Ig and serum proteins were prepared. Cells producing antibodies (C 1.9) which precipitated with IgM and bound to staphylococcal protein A were triple-cloned (C 1.9/3.2) and the antibodies further characterized. Monoclonal antibody C 1.9/3.2 reacted with an IgM determinant present on serum IgM from horses of several breeds. Studies with 125I-labeled IgM revealed the presence of this determinant on all IgM molecules. The monoclonal antibody enabled quantitation of IgM in presuckling foal and adult horse sera, using rocket electrophoresis. This procedure was used because presumably it gives a positive precipitation reaction over a wide range of antigen-antibody ratios. The C 1.9/3.2 monoclonal antibody recognized an exposed mu-chain determinant on live B lymphocytes, as determined by immunofluorescence. Also, IgM-containing cells could be identified in acetone-fixed frozen sections of lymphoid tissue. Sera from several other species carry the determinant identified by C 1.9/3.2, suggesting that the reagent may be useful for IgM studies in other species.  相似文献   
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