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161.
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The California net energy system has gained wide acceptance as a method for predicting rates of gain in growing and finishing beef animals. Researchers at the University of Kentucky, in co-operation with agricultural scientists in two regional research projects, NC-114 and S-156, have developed an interactive model that enhances the usefulness of the net energy system by including skeletal size, feed quality, temperature and relative humidity to determine feed intake and utilisation. Basically, the intake based on feed availability, nutrient composition, potential skeletal size and heat loss potential. After the feed is consumed, it is utilised according to the productive status of the animal, i.e. growth, lactation, foetal development, etc., using a modified form of the net energy system to predict weight change.The model allows a researcher to easily modify environment, feed, breed characteristics and productive status so as to evaluate their influence on the performance of the animal. 相似文献
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Schönfelder A Schrödl W Krüger M Richter A Sobiraj A 《Berliner und Münchener tier?rztliche Wochenschrift》2005,118(5-6):240-246
The change of haptoglobin concentration in cattle with dystocia after torsio uteri which lead to Caesarean section is regarded in contrast to haptoglobin concentrations in cattle at parturitions with undisturbed puerperium and Caesarean section without torsio uteri intra partum. Animals with natural parturition had low haptoglobin concentrations with slight changes, for a slightly increased haptoglobin concentration was seen as physiologic. Also surgical treatment such as Caesarean section did not result in changes of haptoglobin concentration. Thus, the curve of animal patients with anomalies concerning position or with a too large fetus (relatively or absolutly) was nearly identical to the curve of animals with regular parturitions over the first four days after surgery. Not before the fifth day after surgery, a moderate increase of haptoglobin could be observed. Animals with dystocia after torsio uteri intra partum showed significantly higher haptoglobin concentrations in contrast to controls over the time of investigation. The correlation of haptoglobin concentrations in animal patients with torsio uteri bin concentration shortly after surgery an additionally significant increase of haptoglobin concentration could be observed in later fertile cattles but not in later infertile cattle with torsio uteri. In two cows with torsio uteri and ovariohysterectomy haptoglobin concentrations decreased rapidly. Haptoglobin concentration may serve as an indicator for the degree of impairment of the uterus during a parturition as well as a predictor for regenerative potential. 相似文献
165.
OBJECTIVE: To characterize the use of antiemetic agents in dogs with canine parvovirus (CPV)-associated enteritis in a veterinary teaching hospital. DESIGN: Retrospective case series. ANIMALS: 77 dogs with CPV-associated enteritis. PROCEDURE: Medical records of 560 dogs with confirmed CPV-associated enteritis that were admitted to a veterinary teaching hospital were reviewed. Exclusion criteria included vaccination against CPV infection within the preceding 2 weeks, hospitalization for < 24 hours or removal from the hospital against advice, or an incomplete record. Signalment, duration of hospitalization, and daily antiemetic administrations were assessed; WBC counts and clinical findings were used to classify dogs as having systemic inflammatory response syndrome (SIRS). RESULTS: 77 dogs were included in the study; 55 (71%) received antiemetics (53 received metoclopramide at least once). Seventy-one dogs survived, and 6 dogs died (all 6 received antiemetics). Compared with dogs that did not receive antiemetics, duration of hospitalization was significantly longer for antiemetic-treated dogs. Daily values of rectal temperature and heart and respiratory rates did not predict administration of antiemetics or duration of hospitalization; however, compared with survivors, SIRS developed more frequently among nonsurvivors. Assessment of emetic events recorded hourly for 17 dogs indicated that antiemetic treatment did not control emesis. CONCLUSIONS AND CLINICAL RELEVANCE: Many dogs with CPV-associated enteritis had persistent vomiting despite antiemetic administration. The apparent difference in duration of hospitalization between antiemetic-treated dogs and other dogs may reflect a difference in disease severity between groups, although antiemetic-associated adverse events (e.g., signs of depression, hypotension, and immune modulation) may prolong hospitalization. 相似文献
166.
OBJECTIVE: To evaluate platelet surface-associated P-selectin, mean platelet component concentration (MPC), mean platelet component distribution width (MPCDW), mean platelet volume (MPV), and platelet distribution width (PDW) for detection of activated platelets in dogs with septic and nonseptic inflammatory disease. ANIMALS: 20 healthy dogs and 20 dogs with septic and nonseptic inflammatory disease. Procedures-Platelet surface-associated P-selectin (expressed as the median fluorescence intensity [MFI] of the platelet population), MPC, MPCDW, MPV, and PDW were determined in 20 healthy adult dogs, and reference ranges were calculated. These parameters were also determined in 11 dogs with nonseptic and 9 dogs with septic inflammatory disease and evaluated to determine which parameters were useful for detection of activated platelets. Results-12 dogs with inflammatory disease had P-selectin greater than the upper limit of the reference range, whereas 16 dogs with inflammatory disease had MPC lower than the lower limit of the reference range. All dogs in which P-selectin was greater than the upper limit of the reference range had MPC lower than the lower limit of the reference range. The correlation coefficient for P-selectin and MPC was 0.62. Differences in the MPCDW, MPV, and PDW in most dogs with inflammatory disease (compared with healthy dogs) were found; however, the correlation coefficients for P-selectin and MPCDW, MPV, and PDW were low. CONCLUSIONS AND CLINICAL RELEVANCE: Platelet surface-associated P-selectin and MPC appeared to be useful to detect activated platelets in most dogs with septic and nonseptic inflammatory disease. 相似文献
167.
Hancock RB Lanz OI Waldron DR Duncan RB Broadstone RV Hendrix PK 《Veterinary surgery : VS》2005,34(3):273-282
OBJECTIVE: To compare the effects of postoperative pain after ovariohysterectomy by harmonic scalpel-assisted laparoscopy (HALO) and traditional ovariohysterectomy (OVH) in dogs. STUDY DESIGN: A randomized, blinded, prospective study. SAMPLE POPULATION: Sixteen, purpose-bred, intact female, Beagle dogs. METHODS: Dogs were divided into 2 groups: Group 1 (8 dogs), which had OVH by HALO, and Group 2 (8 dogs), which had traditional OVH. Physiologic data, abdominal nociceptive threshold scores, and University of Melbourne pain scores (UMPS) were recorded at 2, 6, 12, 24, 48, and 72 hours after surgery. Blood samples for measurement of plasma cortisol, glucose, and creatine phosphokinase (CPK) concentrations were collected at the time of the incision, and 2, 6, 12, 24, 48, and 72 hours after surgery. RESULTS: No significant surgical complications occurred. The HALO mean surgical time was significantly longer (55.7 minutes) than traditional OVH (31.7 minutes). No significant differences were observed between groups for the pain measures of heart rate, respiratory rate, temperature, CPK, and glucose concentrations. The OVH group had significantly higher mean plasma cortisol levels at hour 2 after surgery than the HALO group (P=.0001). The mean UMPS were significantly higher in OVH than the HALO group at all postoperative times (P=.0001). The mean nociceptive threshold measurements revealed significantly higher tolerated palpation pressures in HALO than OVH at all postoperative times, except hour 72 (P=.0002). CONCLUSIONS: Dogs appeared to be in less pain with HALO than OVH. The harmonic scalpel coagulated ovarian and uterine vessels completely with minimal collateral damage to surrounding tissues. CLINICAL RELEVANCE: HALO is a safe alternative to OVH and offers a minimally invasive and less painful method of surgery. 相似文献
168.
The gain in structural matter had a linear course with a corresponding feeding intensity and depending on the period of fattening. However, the animals given high-energy diets deposited 130 g protein per day during the first fattening period, this deposition being compensated in the course of further growth by a considerably lower deposition in the sense of aequifinality. Up to a live weight of 70 kg, animals subjected first to restricted feeding and then to fully balanced feeding revealed the highest protein deposition during the last period of fattening, this fact emphasizing the leanmeat character of the animal material used. The daily fat deposition was found clearly determined by energy intake and independent of amino acid supply. Lysine conversion was influenced by the intake of lysine and energy. Under feeding to norm it reached some 40 and 30% during the first and second periods of fattening, respectively. 相似文献
169.
Suspension concentrates are dispersions of sparingly soluble active ingredients in water or in organic solvents and generally contain particles with diameters in the range 0.4–12 μm. Four particle size analysis techniques were tested for their suitability for these formulations. Experimental details which are of particular significance for these formulations and methods of presenting the results are discussed for the different techniques. It was found that: the electron microscope was suitable but time-consuming when used without counting devices; the optical microscope was reliable only for the coarse samples, i.e. samples with a median of the volume distribution greater than 2 μm; the Coulter counter model TA was quick and reliable; the centrifugal disc photosedimentometer was also quick and reliable but its suitability decreased with increasing particle size. 相似文献
170.