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51.
Endocrine changes in sows with ovarian cysts were determined to be comparable with those in sows in diestrus. Blood samples were collected at frequent intervals from 5 sows affected with cystic ovaries. Concentrations of serum luteinizing hormone, progesterone, estradiol-17 beta, and cortisol were determined by use of established radioimmunoassays. The development of ovarian cysts has been proposed to be associated with a deficiency of luteinizing hormone rather than an intrinsic ovarian abnormality. In contrast, the results of this study demonstrated that tonic and pulsatile luteinizing hormone release were not affected adversely in sows with cystic ovaries. 相似文献
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Stephen Joslyn Suzanna Richards Susanne Boroffka Mark Mitchell Gawain Hammond Martin Sullivan 《Veterinary radiology & ultrasound》2014,55(1):63-67
Enhancement of extra‐ocular muscles has been reported in cases of orbital pathology in both veterinary and medical magnetic resonance imaging. We have also observed this finding in the absence of orbital disease. The purpose of this retrospective study was to describe extra‐ocular muscle contrast enhancement characteristics in a group of dogs with no known orbital disease. Magnetic resonance images (MRI) from dogs with no clinical evidence of orbital disease and a reportedly normal MRI study were retrieved and reviewed. Contrast enhancement percentages of the medial, lateral, ventral, and dorsal rectus muscles were calculated based on signal‐to‐noise ratios that were in turn determined from hand‐traced regions of interest in precontrast, immediate postcontrast and 10‐min postcontrast scans. Comparison measurements were made in the pterygoid muscle. Contrast enhancement of the extra‐ocular muscles was observed in all patients (median contrast enhancement percentage 45.0%) and was greater than that of pterygoid muscle (median contrast enhancement percentage 22.7%). Enhancement of the extra‐ocular muscles persisted 10 min after contrast administration (median contrast enhancement percentage 43.4%). Findings indicated that MRI contrast enhancement of extra‐ocular muscles is likely normal in dogs. 相似文献
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Rose-Dye TK Burciaga-Robles LO Krehbiel CR Step DL Fulton RW Confer AW Richards CJ 《Journal of animal science》2011,89(4):1193-1200
Remote rumen temperature monitoring is a potential method for early disease detection in beef cattle. This experiment was conducted to determine if remotely monitored rumen temperature boluses could detect a temperature change in steers exposed to bovine viral diarrhea virus (BVDV) and challenged with a common bovine respiratory disease pathogen, Mannheimia haemolytica (MH). Twenty-four Angus crossbred steers (BW = 313 ± 31 kg) were allotted to 1 of 4 treatments: 1) no challenge (control); 2) challenge by a 72-h exposure to 2 steers persistently infected with BVDV; 3) bacterial challenge with MH; and 4) viral challenge by a 72-h exposure to 2 steers persistently infected with BVDV followed by bacterial challenge with MH (BVDV + MH). Remotely monitored rumen temperature boluses programmed to transmit temperature every minute were placed in the rumen before the time of exposure to steers persistently infected with BVDV. Rectal temperatures were taken before MH challenge (0) and at 2, 4, 6, 12, 18, 24, 36, 48, 72, and 96 h after MH challenge. Rumen temperatures were recorded 3 d before (-72 h; period of BVDV exposure) through 14 d after (336 h) MH challenge. Rumen temperatures were analyzed as a randomized complete block design with a 2 × 2 factorial arrangement of treatments and a first-order autoregressive covariance structure for repeated measures. A treatment × day interaction was observed for average daily rumen temperature (P < 0.01). A treatment difference (P < 0.01) was observed on d 0, when MH-challenged steers had greater rumen temperatures than steers not challenged with MH. There was no BVDV × day interaction (P > 0.01). Rumen temperatures averaged every 2 h resulted in a BVDV × hour interaction (P < 0.01) and an MH × hour interaction (P < 0.01). The BVDV × hour differences occurred at h -18 to -14, 40 to 46, 110, 122, and 144 to 146 (P < 0.01). The MH × hour difference occurred at h 4 to 24 (P < 0.01). Maximum rumen temperature was increased (P < 0.01) for BVDV (0.8 °C), MH (1.2 °C), and BVDV + MH (1.3 °C) compared with the control. On average, rumen temperatures measured by the boluses at the same time points as the rectal temperatures were 0.13 °C less than rectal temperatures, and the 2 body temperatures were highly correlated (r = 0.89). Rumen temperature boluses appear to have potential as a tool for detecting temperature changes associated with adverse health events such as exposure to bovine respiratory disease and BVDV. 相似文献
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Hsiao-Wei Chen George W. Small Alison Motsinger-Reif Steven E. Suter Kristy L. Richards 《Veterinary immunology and immunopathology》2014,157(3-4):125-130
The use of specific immunoglobulin heavy chain variable region (VH) genes has been associated with increased patient survival in human B-cell lymphomas (hBCL). Given the similarity of human and canine BCL (cBCL) in morphology and clinical treatment, we examined the choice of VH in cBCL and determined whether VH gene selection was a distinct feature associated with survival time in dogs. VH gene selection and mutational status in 52 cBCL, including 29 diffuse large B-cell lymphomas (cDLBCL, the most common subtype of cBCL), were analyzed by comparison with the 80 published canine germline VH gene sequences. We further examined the prognostic impact of the subgroups defined by these features on canine survival. We found that VH1-44 was preferentially expressed in the majority of the 52 cBCLs (60%) as well as in the majority of the cDLBCL subset (59%). VH1-44 gene expression was associated with a statistically better overall survival (p = 0.039) in cBCL patients, as well as in the cDLBCL subset of patients (p = 0.038). These findings suggest that VH gene selection in cBCL is not random and may therefore have functional implications for cBCL lymphomagenesis, in addition to being a useful prognostic biomarker. 相似文献
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G. A. White P. J. Richards S. Wu K. H. Mellits J. Wiseman 《British poultry science》2015,56(4):494-502
There is much interest in quantifying the nutritional value of UK wheat distillers dried grains with solubles (W-DDGS) for livestock species. A study was designed to evaluate caecal parameters (pH, short chain fatty acids (SCFAs) and bacterial diversity) in layer hens fed on balanced diets containing graded concentrations of W-DDGS.
A total of 32 layer hens (Bovans Brown strain at 27 weeks of age) were randomly allocated to one of 4 dietary treatments containing W-DDGS at 0, 60, 120 or 180 g/kg. Each treatment was fed to 8 replicate individually housed layer hens over a 5-d acclimatisation period, followed by a 4-week trial. Individual feed intakes were monitored and all eggs were collected daily for weeks 2, 3 and 4 of the trial, weighed and an assessment of eggshell “dirtiness” made. All hens were culled on d 29 and caecal pH and SCFAs measured. Polymerase chain reaction denaturing gradient gel electrophoresis of the bacterial 16 S rDNA gene was used to assess total bacterial diversity of luminal caecal content from hens fed the 0 and 180 g W-DDGS/kg diets. Unweighted pair group method with arithmetic mean (UPGMA) dendrograms were generated from DGGE banding patterns.
Increasing W-DDGS dietary concentrations resulted in a more acidic caecal environment. Caecal SCFAs were unaffected by diet aside from a quadratic effect for molar proportions of isobutyric acid. Diversity profiles of the bacterial 16S rRNA gene from luminal caecal contents were unaffected by W-DDGS inclusion.
The results of the current study suggest that W-DDGS can be successfully formulated into nutritionally balanced layer diets (supplemented with xylanase and phytase) at up to 180 g/kg with no detrimental effects to the caecal environment.
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Richards CJ Swanson KC Paton SJ Harmon DL Huntington GB 《Journal of animal science》2003,81(4):1051-1056
Our objective was to evaluate the effect of postruminal protein infusion on pancreatic exocrine secretions. One Holstein, two crossbred, and five Angus steers (305 +/- 5 kg) with pancreatic pouch-duodenal reentrant cannulas and abomasal infusion catheters were used in a replicated 4 x 4 Latin square. All steers were abomasally infused with 1,050 g/d of raw cornstarch with treatments of 0, 60, 120, or 180 g/d of sodium casein suspended in water to yield 6,000 g/d of infusate daily. Steers were limit-fed (1.5 x NEm; 12 equal portions daily) a 90% corn silage, 10% supplement diet formulated to contain 12.5% CP. Periods consisted of 3 d of adaptation to infusion, 7 d of full infusion, 1 d of collection, and 7 d of rest. Pancreatic juice was collected in 30-min fractions continuously for 6 h. Total juice secreted and the pH of individual fractions were recorded, a 10% subsample was retained to form a composite sample, and remaining fluid was returned to the duodenum. Juice composite samples were stored (-30 degrees C) until analyzed for total protein and activities of alpha-amylase, trypsin, and chymotrypsin. Casein infusion linearly increased alpha-amylase concentration (182 to 271 units/mL; P < 0.02; 17.5 to 24.6 units/mg of protein; P < 0.03) and secretion rate (26,847 to 41,894 units/h; P < 0.01). Total juice secretion (155 g/h), pH of pancreatic juice (8.13), secretion rate of protein (1,536 mg/h), and concentration of protein (10.2 mg/mL) in pancreatic secretions were not affected (P > 0.05) by casein infusion. Similarly, casein infusion did not change 0.05) trypsin and chymotrypsin concentrations (1,379 and 349 units/L or 0.134 and 0.033 units/mg of protein, respectively) or secretion rates (206 and 52 units/h, respectively). Abomasal infusion of protein with starch stimulated a greater pancreatic secretion of alpha-amylase activity into the intestine than infusion of starch alone. 相似文献