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991.
Signs of ascites were observed in only nine of 1863 cattle examined over a period of five years. The ascites was most commonly associated with either primary or secondary cardiac disease; cattle with ascites have a poor prognosis because the condition is usually assocaited with terminal disease. Two animals had cor pulmonale with chronic pneumonia, three had cardiomyopathy, one had bacterial endocarditis, two had thrombosis of the caudal vena cava and one had diffuse abdominal epithelioid mesothelioma.  相似文献   
992.
Postweaning data from 1,111 straightbred and reciprocally crossbred rabbits were analyzed to evaluate Altex and New Zealand White (NZW) breeds for individual growth and litter traits. The Altex is a recently developed sire breed, whereas the NZW is a popular commercial dam breed. Individual fryer growth traits were weaning (28 d; WW) and market (70 d; MW) weights and ADG. Litter traits included litter size (LSW) and total weight of litter at weaning (LWW), 28 to 70 d total feed intake (LFI), feed efficiency (LFE = total litter gain/LFI), survival rate, and within-litter MW uniformity. Least squares models consisted of fixed effects of sire breed, dam breed, season of weaning, doe parity, two- and three-way interactions, and random effects of sire within sire breed, litter within sire x dam breed, and(or) residual error (depending on whether an individual or a litter trait was analyzed). Crossbreeding parameters (direct breed additive, maternal breed, and individual heterosis) were estimated. Altex sires increased WW, ADG, and MW by 40 g (P < 0.10), 2.5 g/d, and 152 g (P < 0.001), respectively. Individual growth traits were not significantly influenced by the maternal breed effect. Litter size at weaning and LWW means were numerically similar for Altex and NZW dams. Direct heterosis increased ADG (1.7 g/d; P < 0.01) and MW (66 g; P < 0.10). In straightbred Altex compared to NZW fryers, ADG and MW were increased by 3.6 g/d and 216 g, respectively (P < 0.001). In Altex (sire) x NZW (dam) crossbred compared to NZW straightbred fryers, WW and MW were heavier (55 and 218 g; P < 0.10 and < 0.001) and ADG was more rapid (4.2 g/d; P < 0.001). For litter traits, Altex compared to NZW sires increased LFI by 1.28 kg (P < 0.10). Individual crossbreeding parameters did not affect (P > 0.05) other litter traits. No relationship existed between breed type of fryer and survival status (chi2 = 2.81; P > 0.25). For litter traits, straightbred Altex had significantly greater LFI by 2.45 kg and increased LFE by 0.015 units relative to NZW. Combined direct breed additive and heterosis effects increased LFI by 1.84 kg (P < 0.05) in Altex (sire) x NZW (dam) crossbreds compared to NZW straightbreds. Also, 25% more Altex (sire) x NZW (dam) crossbred fryers were marketable (body weight > or = 1.8 kg) by 63 d of age than NZW straightbred fryers. These data suggest that crossing Altex bucks to NZW enhanced breeding efficiency of fryer growth performance.  相似文献   
993.
994.
Early-weaned Angus x Simmental heifers were used to evaluate the effects of postweaning nutritional management on feedlot performance, carcass merit, and the relationship of intramuscular and subcutaneous fat deposition to the feed efficiency among heifers fed for a high-quality market. Sixteen heifers were weaned at 73+/-5.5 d of age and grazed on endophyte-infected tall fescue for 18 mo before entering the feedlot (early-weaned-P). Eighty heifers from the following year's calf crop were weaned at 71+/-5.5 d of age and allowed either ad libitum access to a 25% concentrate diet (early-weaned-25C) or limit-fed a 90% concentrate diet (early-weaned-90C) to achieve a similar ADG. Following a 119-d growing period, 16 early-weaned-90C and 16 early-weaned-25C calves were paired based on BW and growth rate and individually fed during the finishing period along with the early-weaned-P heifers. Ultrasound measurements of s.c. and i.m. fat were recorded at approximately 60-d intervals throughout the finishing period. Feed efficiency was regressed against s.c. and i.m. fat, and i.m. fat was regressed on s.c. fat. Despite a similar ADG, early-weaned-90C calves gained more efficiently (P < or = 0.05) in the feedlot than early-weaned-25C calves. Heifers finished as yearlings tended (P < or = 0.10) to gain faster but gained less efficiently (P < or = 0.01) than early-weaned-90C heifers finished as calves. The rate of s.c. and i.m. fat deposition was similar between early-weaned-90C and early-weaned-25C heifer calves. The calves were grouped together for comparison to yearlings. Feed efficiency decreased quadratically (P < or = 0.01) as s.c. fat cover increased. The rate at which feed efficiency decreased relative to increasing s.c. fat cover was similar regardless of age at feedlot entry. However, heifers finished as calves gained more efficiently (P < or = 0.01) than yearlings at any given fat thickness. Feed efficiency decreased linearly (P < or = 0.01) as i.m. fat increased among heifers finished as calves. Additionally, heifers finished as calves deposited i.m. fat at a faster rate relative to s.c. fat (P < or = 0.01) than yearlings. These data suggest that heifers finished as calves produce high-quality carcasses with less s.c. fat cover while gaining more efficiently than heifers finished as yearlings.  相似文献   
995.
Twenty-four dogs and 30 cats with histopathologically confirmed salivary gland neoplasia were retrospectively reviewed in a multi-institutional study. The predominant presenting complaint for animals with salivary gland neoplasia was that of a mass being noted by the owner; other common complaints included halitosis, dysphagia, and exophthalmia. Siamese cats were overrepresented, indicating a possible breed predisposition. The most common histopathological type was simple adenocarcinoma. Cats had more advanced disease at diagnosis than did dogs, and clinical staging was prognostic in dogs. The median survival times for dogs and cats were 550 days and 516 days, respectively.  相似文献   
996.
OBJECTIVE: To describe in horses and ponies a laparoscopic ovariectomy technique facilitated by electrosurgical instrumentation. STUDY DESIGN: Elective ovariectomy was performed in 23 mares using laparoscopic electrosurgical instrumentation. ANIMALS OR SAMPLE POPULATION: Twenty-three mares (13 horses, 10 ponies), aged from 2 to 21 years and weighing 90 to 545 kg. METHODS: Food was withheld for a minimum of 12 hours. Mares were sedated with detomidine hydrochloride (0.02 to 0.03 mg/kg) or xylazine hydrochloride (0.5 to 1.0 mg/kg). Excluding the pony mares, all other mares were restrained in stocks. Portal sites in the paralumbar fossa region were desensitized with 2% mepivacaine. Abdominal insufflation was achieved through a teat cannula positioned in the ventral abdomen or a Verres-type needle placed through the paralumbar fossa. After trocar and laparoscope insertion, the ipsilateral ovary and mesovarium were identified, and the mesovarium, tubal membrane, and proper ligament were infiltrated with 2% mepivacaine. The mesovarium was coagulated using bipolar or monopolar electrosurgical forceps and transected sequentially from cranial to caudal until the ovary was completely freed and then removed. The contralateral ovary was removed in a similar fashion through the opposite paralumbar fossa. RESULTS: Bipolar and monopolar electrosurgical forceps were easy to use and provided adequate coagulation of vessels within the mesovarium. Two mares were euthanatized after the procedure for unrelated reasons. One mare had mild signs of colic 24 hours after ovariectomy. In 1 pony mare, the incision used to remove one ovary dehisced on the 5th postoperative day and was allowed to heal by second-intention. No long-term complications had occurred in 11 horses and 10 ponies, 6 to 24 months after surgery. CONCLUSION: Laparoscopic ovariectomy and hemostasis of the mesovarium can be easily accomplished using electrosurgical instrumentation. CLINICAL RELEVANCE: Standing laparoscopic ovariectomy, using electrosurgical instrumentation, is an effective and safe technique to provide hemostasis of the mesovarium in mares.  相似文献   
997.
This study was the first to examine the seroprevalence of Ornithobacterium rhinotracheale (ORT) within a commercial egg layer population. Serum samples collected from egg production companies were examined by serum plate agglutination test (SPAT) and outer membrane protein-based enzyme-linked immunosorbent assay (ELISA). Results show that 90% of layer flocks were positive by SPAT and 100% by ELISA. Of the pullet flocks examined, 43% and 52% were positive by SPAT and ELISA, respectively. Our study indicates that the prevalence of ORT antibody is high in the commercial layer population, suggesting that this respiratory pathogen can easily spread through multiple-age layer farms from older flocks to newly housed pullet flocks.  相似文献   
998.
The nitrogen pool of piglets weighing 19.4 +/- 1.4 kg at the beginning of the experiment was labeled with an oral application of ([15N]H4)2SO4 (1.26 [15N]-atom percent excess of dietary N) over a period of 7 d. The labeling period was followed by an equilibration period of 7 d without feeding the labeling compound. The two experimental diets were based on wheat (53%) and rye (25%) and were fed either with or without a xylanase containing enzyme preparation over both experimental periods. Additionally, diets were supplemented with an indigestible marker during the 2nd period of the experiment to allow the calculation of endogenous N-losses in subsequent segments of the digestive tract of the pigs. These endogenous N-losses were estimated at the end of the experiment by analyzing feces, ingesta and urine for [15N]-enrichment assuming that [15N]-enrichment of urine represents the [15N]-enrichment of the precursor pool. Endogenous N-losses were not significantly affected by xylanase addition at any measurement site (stomach, 3 sections of the small intestine, total digestive tract). Endogenous N-proportions of total nitrogen amounted on average for the six pigs to 42 +/- 11% and 56 +/- 5% at the last section of the small intestine and over the whole digestive tract, respectively, which corresponded to endogenous N-losses of 2.8 +/- 1.3 g N/kg DM and 2.0 +/- 0.3 g N/kg DM, respectively.  相似文献   
999.
Toltrazuril sulfone (Ponazuril®) is a triazine-based anti-protozoal agent with highly specific actions against apicomplexan group of organisms, which are undergoing intensive investigation. Toltrazuril sulfone may have clinical application in the treatment of Neospora. caninum and other protozoal infections in cattle. To evaluate absorption, distribution, and elimination characteristics of toltrazuril sulfone in cattle, a sensitive validated quantitative high-pressure liquid chromatography method for toltrazuril sulfone in bovine biological fluids was developed. After a single oral dose of toltrazuril sulfone at 5 mg/kg (as 150 mg/g of Marquis®; Bayer HealthCare, Shawnee Mission, KS, USA), samples from six cows showed good plasma concentrations of toltrazuril sulfone, which peaked at 4821 ng/mL ± 916 (SD) at 48 h postadministration. Thereafter, plasma concentration declined to 1950 ng/mL ± 184 (SD) at 192 h after administration with an average plasma elimination half-life of ∼58 h. Following oral dose of toltrazuril sulfone, the observed peak plasma concentrations were in relatively close agreement ranging from the lowest 3925 ng/mL to the highest of 6285 ng/mL with the mean peak plasma concentration being 4821 ng/mL. This study shows that toltrazuril sulfone is relatively well absorbed after oral dose in cattle. These results are therefore entirely consistent with and support the reported clinical efficacy of toltrazuril sulfone in the treatment of experimentally induced clinical cases of N. caninum and other protozoal-mediated bovine diseases.  相似文献   
1000.
The enterotoxigenic Escherichia coli (ETEC) F4ac is a major cause of diarrhoea in newborn and young pigs. The locus for the intestinal ETEC F4ac receptor (F4acR) has been mapped to pig chromosome (SSC) 13q41 with known homology to human chromosome (HSA) 3q21 and q29. However, the causative gene and mutation(s) remain unknown. The aim of this study was to characterize gene-derived markers on SSC13q41 for fine mapping of the F4acR locus, and construct a high-resolution pig–human comparative map to select positional candidate genes for F4acR. Pig-specific sequence-tagged site markers were developed for 20 genes that are located in a 6.8-Mb region on HSA3q21 and q29, and a total of 34 single-nucleotide polymorphisms (SNPs) were identified in 14 of 20 markers developed. Eighteen markers were mapped to SSC13q41, while the other two markers ( PLXNA1 and KLF15 ) were assigned to SSC13q32 and SSC7q13, respectively, by radiation hybrid mapping. This result showed that there was a small conserved segment on SSC7 corresponding to HSA3q21. A framework map comprising 18 markers on SSC13q41 was established, refining the synteny breakpoint on SSC13q41 to a region of 12.3 centiRay. The comparative radiation hybrid (RH) map revealed three interesting candidate genes for F4acR from the human genome, viz. MUC4 , MUC13 and MUC20 . Linkage analysis with six marker polymorphisms revealed that MUC4 had the most significant linkage with the F4acR locus.  相似文献   
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