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941.
942.
In situ and in vivo digestibility experiments were conducted to determine the acceptability, digestibility, and safety of a return chewing gum/packaging (G/P) material mixture when fed to steers. In the in situ experiment, both ruminal and intestinal disappearances were measured. Two ruminally and duodenally cannulated steers, which were given free access to alfalfa hay (AH), were used in this study. Duplicate Dacron bags containing the G/P were incubated in the rumen for 0, 3, 6, 12, 24, and 48 h. After ruminal incubation, the 12-, 24-, and 48-h bags were placed in the duodenum and collected in the feces to determine intestinal disappearance. In situ ruminal DM disappearance was greater than 70% for all substrates tested at 0 h, indicating high solubility of the substrates in water, and began to reach a plateau after 12 h of incubation. Intestinal in situ disappearance was not different (P>.25) from zero. In the digestion trial, four ruminally cannulated steers (337+/-21.3 kg BW; mean +/- SD) were used in a 4x4 Latin square design with the following treatments: 0) 50% corn (C), 50% AH; 10) 45% C, 45% AH, 10% G/P; 20) 40% C, 40% AH, 20% G/P; 30) 35% C, 35% AH, 30% G/P. Steers fed G/P-containing diets had greater (P<.01) DMI than the control steers. Increasing the G/P resulted in a linear (P<.05) increase in DMI. Apparent DM digestibility tended to be higher (P<.10) for the G/P-containing diets than for the control. A quadratic effect (P<.05) on digestible DMI was observed, with greater (P<.01) digestible DMI values for G/P-containing diets (4.8 vs. 5.8 kg/d). Digestible organic matter and total nonstructural carbohydrate intakes followed trends similar to those of DM. Apparent aluminum digestibility of G/P-containing diets was not different (P>.13) from zero. The level of G/P in the diet had no effect (P>.2) on total VFA concentration or ruminal pH. There was a linear decrease (P<.01) in the molar percentage of isobutyrate and isovalerate in addition to a linear increase (P<.01) in butyrate and valerate with increasing levels of G/P. There was a quadratic effect (P<.01) on molar proportions of acetate and propionate and on the acetate:propionate ratio. Results of both experiments suggest that G/P may be fed to safely replace up to 30% of corn-alfalfa hay diets for growing steers with advantages in improving DMI and digestibility.  相似文献   
943.
OBJECTIVE: To evaluate the efficacy of inhaled nitric oxide (NO) in anesthetized healthy newborn foals with experimentally induced pulmonary hypertension. ANIMALS: Five 1- to 3-day-old foals. PROCEDURE: Anesthesia was induced and maintained with propofol, and foals were intubated and mechanically ventilated. Systemic pressure and pulmonary arterial pressure (P(PA)) were recorded every 30 seconds. Hypertension was induced via a hypoxic gas mixture or chemical vasoconstriction, using the thromboxane mimetic U46619. Nitric oxide was added at a concentration of 80 parts per million (ppm) for 6 minutes under baseline conditions and during pulmonary hypertension-induced alveolar hypoxia (inspired oxygen concentration = 0.08). Nitric oxide (20, 40, 80, and 160 ppm) was evaluated during U46619-induced hypertension. Samples for determination of arterial blood gas tensions were collected before and after each NO treatment. RESULTS: Inhaled NO (approx 80 ppm) did not have an effect on baseline variables. Infusion of U46619 (0.35 +/- 0.04 microg/kg of body weight/min) or alveolar hypoxia resulted in increased P(PA) and decreased arterial oxygenation (PaO2) and hemoglobin saturation (HbSat). The increase in P(PA) was attenuated, in a dose-dependent manner, by NO during U46619 infusion and reversed by NO during induced hypoxemia. The PaO2 and HbSat were significantly improved at all NO doses during U44619 infusion but not during alveolar hypoxia. For all inhaled NO concentrations, nitrogen dioxide and methoglobin values were < 5 ppm and 3%, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Nitric oxide is a potent, selective vasodilator of the pulmonary circulation in healthy newborn foals. Inhaled NO may have value as a therapeutic agent in foals with pulmonary hypertension.  相似文献   
944.
A reliable antemortem diagnostic method is needed for determining infection with canine distemper virus (CDV). The utility of immunohistochemical detection of CDV antigen was examined was examined for samples of nasal and footpad epithelium and haired skin in dogs with and without detectable CDV antigen in the lung and/or brain. Tissues from 57 dogs at risk of CDV infection were tested. Viral antigen was found in the lung and/or brain of 28 dogs. Among these dogs, viral antigen was demonstrated in the epithelial cells of the nasal mucosa in 24 of 27 dogs, in the footpad epithelium in 24 of 26 dogs, and in the haired skin of the dorsal neck in 26 of 27 dogs. Among the 29 dogs without CDV antigen in either the lung or brain, 1 dog had positive staining for viral antigen in the skin and nasal mucosa. Biopsies of haired skin of the dorsal neck, which is relatively simple to sample, can be used for immunohistochemical testing for acute and subacute infection with CDV.  相似文献   
945.
We retrospectively evaluated the medical records and obtained follow-up information for nine horses which had been treated for cecocolic intussusception (CCI) between January 1982 and April 1998. During the 16-year study period, CCI was diagnosed in nine of 748 horses in which exploratory celiotomy was undertaken for abdominal pain, representing an incidence of 1.2%. Most affected horses (78%) were less than four years of age (median age was 12 months, age range was five months to 15 years). Cecocolic intussusception affected male horses (78%) more commonly than female horses. The most common clinical presentation was abdominal pain of a severe, acute nature or milder but recurrent signs of abdominal pain persisting in spite of conservative treatment for several days. Correction of CCI by either simple reduction or reduction followed by partial typhlectomy was successful if compromise of the intestine by devitalization and adhesion formation was not found at surgery. Definitive diagnosis of CCI necessitates exploratory celiotomy, although an ultrasonographic examination of the abdomen may confirm the diagnosis in some cases. When recognized early during the course of disease, surgical correction of CCI is associated with a favorable outcome; of the eight horses which underwent surgery in our series, five horses (63%) survived surgical correction of CCI. Handling of compromised gut during reduction of CCI necessitates extreme caution because the risk of intestinal tearing is quite high.  相似文献   
946.
1.?The objectives were to quantify the presence of neurogenic inflammation in 4 regions of the upper digestive tract of anaesthetised ducks (post-pharynx, pseudo-crop, transition between the pseudo-crop and the proventriculus, and proventriculus) after application of HCl stimulation of up to 4?M in the pseudo-crop.

2.?The second objective was to quantify the presence of neurogenic inflammation in the same digestive tract regions as mentioned above during 4 feeding periods of foie gras production (rearing, preparation to force-feeding, and second and last meals of the force-feeding period).

3.?Extravasation increased above a HCl stimulation threshold of 2?M. Furthermore, more extravasation was observed in the proventriculus compared to the other regions (P?

4.?Highest extravasation responses were observed in the proventriculus and the pseudo-crop at the end of the preparation period, and in the proventriculus after the second forced meal, compared with the rearing period (P?

5.?Such a kinetic could be indicative of a relative mildness of the irritant components associated with this feeding practice.  相似文献   

947.
Four experiments were conducted to determine the interactive effects of pharmacological amounts of Zn from ZnO and Cu from organic (Cu-AA complex; Cu-AA) or inorganic (CuSO(4)) sources on growth performance of weanling pigs. The Cu was fed for 4 (Exp. 1) or 6 (Exp. 2, 3, and 4) wk after weaning, and Zn was fed for 4 (Exp. 1) or 2 (Exp. 2, 3, and 4) wk after weaning. Treatments were replicated with 7 pens of 5 or 6 pigs per pen (19.0 ± 1.4 d of age and 5.8 ± 0.4 kg of BW, Exp. 1), 12 pens of 21 pigs per pen (about 21 d of age and 5.3 kg of BW, Exp. 2), 5 pens of 4 pigs per pen (20.3 ± 0.5 d of age and 7.0 ± 0.5 kg of BW, Exp. 3), and 16 pens of 21 pigs per pen (about 21 d of age and 5.7 kg of BW, Exp. 4). In Exp. 1 and 2, Cu-AA (0 vs. 100 mg/kg of Cu) and ZnO (0 vs. 3,000 mg/kg of Zn) were used in a 2 × 2 factorial arrangement. Only Exp. 1 used in-feed antibiotic (165 mg of oxytetracycline and 116 mg of neomycin per kilogram feed), and Exp. 2 was conducted at a commercial farm. In Exp. 3, sources of Cu (none; CuSO(4) at 250 mg/kg of Cu; and Cu-AA at 100 mg/kg of Cu) and ZnO (0 vs. 3,000 mg/kg of Zn) were used in a 3 × 2 factorial arrangement. In Exp. 4, treatments were no additional Cu, CuSO(4) at 315 mg/kg of Cu, or Cu-AA at 100 mg/kg of Cu to a diet supplemented with 3,000 mg/kg of Zn from ZnO and in-feed antibiotic (55 mg of carbadox per kilogram of feed). In Exp. 1 and 2, both Zn and Cu-AA improved (P < 0.001 to P = 0.03) ADG and ADFI. No interactions were observed, except in wk 1 of Exp. 2, where Zn increased the G:F only in the absence of Cu-AA (Cu-AA × Zn, P = 0.04). A naturally occurring colibacillosis diarrhea outbreak occurred during this experiment. The ZnO addition reduced (P < 0.001) the number of pigs removed and pig-days on antibiotic therapy. In Exp 3, ADFI in wk 2 was improved by Zn and Cu (P < 0.001 and P = 0.09, respectively) with no interactions. In wk 1, G:F was reduced by ZnO only in the absence of Cu (Cu × Zn, P = 0.03). Feeding Zn decreased fecal microbiota diversity in the presence of CuSO(4) but increased it in the presence of Cu-AA (Cu source × Zn, P = 0.06). In Exp. 4, Cu supplementation improved the overall ADG (P = 0.002) and G:F (P < 0.001). The CuSO(4) effect on G:F was greater (P < 0.001) than the Cu-AA effect. Our results indicate that pharmacological amounts of ZnO and Cu (Cu-AA or CuSO(4)) are additive in promoting growth of pigs after weaning.  相似文献   
948.
The aim of this study was to describe changes in cardiac morphology, systolic function and some peripheral hemodynamic parameters during normal pregnancy in dogs. Twenty healthy bitches, 10 pregnant (PG) and 10 non-pregnant controls (CG), were evaluated every 10 days using echocardiography from day 0 of the estrus cycle to parturition or to day 65 for the PG and CG groups, respectively. Systolic blood pressure (SBP) and uterine artery resistance index (RI) were also assessed. Throughout the study, the shortening fraction and cardiac output increased up to 30% vs. 5% (P<0.01) and 45% vs. 2% (P<0.01) in the PG and CG groups, respectively. In contrast, SBP and RI diminished up to 20% vs. 1% (P<0.01) and 29% vs. 0% (P<0.01) in the PG and CG groups, respectively. In conclusion, a decrease in afterload, an increase in cardiac output and cardiac hypertrophy appear to be the result of the hemodynamic modifications occurring during pregnancy in dogs.  相似文献   
949.
Objective-To describe clinical features of oral and maxillofacial osteomas in cats. Design-Retrospective case series. Animals-7 cats with oral or maxillofacial osteoma or both. Procedures-Medical records were reviewed for information on signalment, history, clinical signs, physical examination findings, diagnostic imaging findings, results of serum biochemical analyses and histologic testing, surgical procedures performed, and perioperative complications. Outcome was determined on the basis of follow-up telephone interviews of owners. Results-Cats ranged from 1 to 23 years of age. Clinical signs were observed in 5 cats and were attributed to the presence of the mass. Diagnostic imaging (radiography and computed tomography) and histologic examination confirmed the diagnosis of osteoma. Three cats were euthanatized; 1 cat was treated by mandibulectomy, 1 was treated by maxillectomy, and 2 were treated by debulking. At the time of follow-up at least 1 year after surgery, all 4 treated cats were alive, with owners reporting an acceptable quality of life. Conclusions and Clinical Relevance-Osteoma of the oral and maxillofacial regions is an uncommon tumor in cats. Most cats are examined during an advanced stage of the disease, when treatment options may be limited. Although osteoma is a benign tumor, the recommendation is to perform a clinical evaluation, diagnostic imaging, biopsy, and treatment early in the disease process, when less invasive surgical approaches may be feasible.  相似文献   
950.
Multiple fecal samples were collected from growing Angus bulls (264 to 419 kg of BW, 3.0 to 11.4 kg/d of DMI) to predict DMI of a corn-silage-based diet. Contemporaneous digestion trials were conducted with the same diet in 12 steers in yr 1 to 3 and bulls in yr 4. Near-infrared spectra from fecal samples (n = 730 from 282 growing bulls, n = 240 from 36 steers and 12 bulls for digestion trials) were obtained from dried and ground fecal samples, and modified partial least squares regression was used to develop equations to predict DMI and DM digestibility (DMD). Although mean predicted DMI of the growing bulls (7.52 ± 0.04 kg/d or 22.4 ± 0.1 g/kg of BW) was within 2% of mean measured DMI (7.63 ± 0.06 kg/d or 22.7 ± 0.1 g/kg of BW), the mean of paired differences within samples (0.11 ± 0.04 kg/d or 0.3 ± 0.1 g/kg of BW) was greater (P < 0.01) than zero. Measured DMD (72.3 ± 0.5%) was identical (P < 0.97) to predicted DMD (72.3 ± 0.5%), and DMD for bulls in the digestion trial did not differ (P < 0.27) from DMD for steers. Prediction of intake requires incorporation of some measured values from the set of fecal samples to be predicted. Lack of similarity between spectra of fecal grab samples from the growing bulls and daily fecal collection of steers and bulls in the digestion trials in this study indicates the need for further verification before prediction of DMD with fecal grab samples.  相似文献   
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