Serological changes observed in horses infected with Anoplocephala perfoliata after treatment with praziquantel and natural reinfection

The serological changes in two groups of horses known to be harbouring Anoplocephala perfoliata were studied; 12 were treated with 1.5 mg/kg praziquantel and 200 microg/kg ivermectin, and 14 were treated with 200 microg/kg ivermectin. Serological and faecal analyses were carried out on each animal at intervals for 758 days. The titres of antibodies specific for A perfoliata decreased from the day of treatment to day 28 in both groups, and continued to decrease in the group treated with praziquantel and ivermectin, with the first significant decrease from the other group at day 121. From day 151 to day 295 the first significant increase in antibody levels in the group treated with both drugs was observed; no A perfoliata eggs were detected in the faeces of these animals until day 295 when five of the 10 were positive.     

Applicant expectations and decision factors for jobs and careers in food-supply veterinary medicine

This article examines the job expectations of applicants as reported by recruiters interviewing food-supply veterinary medicine (FSVM) candidates and the career-choice decision factors used by year 3 and 4 veterinary students pursuing careers in FSVM. The responses of 1,047 veterinary recruiters and 270 year 3 and 4 students with a food-supply focus from 32 colleges of veterinary medicine in the United States and Canada were examined. Recruiters were asked to report the two most important job factors applicants took into account when deciding to accept an offer; students were asked the two most important reasons for choosing a career in FSVM and the two most important benefits of working as a food-supply veterinarian. Recruiters reported that high salaries and good benefits are the two most important decision factors. Interest in the food-animal career area and a desire for a rural, outdoor lifestyle were the top reasons students gave for choosing an FSVM career. Students saw the enjoyment of working with and helping producers and food animals as the most important benefits of a career in FSVM.     

Shiga toxin-producing Escherichia coli (STEC) isolated from healthy dairy cattle in southern Brazil

Over a period of 1 year, the production of verotoxin was investigated in 1127 Escherichia coli isolated from 243 dairy cattle from 60 small farms in southern Brazil. Vero cell assay was used to detect toxins in culture supernatants from E. coli isolated from bovine feces. Shiga toxin-producing E. coli (STEC) detection rates were 95% (57 of 60) for farms and 49% (119 of 243) for cattle. Prevalence of STEC-positive cattle in the farms ranged from 0 to 100%. Ninety-six percent (315 of 327) of the STEC isolates did not react in the panel of sera used for typing. Twelve isolates, all non-motile, belonged to serogroups previously associated with human diseases, and 67% (8 of 12) were of only two serotypes (O91:H- and sorbitol-fermenting O157:H-). These results indicate that dairy cattle from the region surveyed may be a source of STEC potentially pathogenic for humans.     

Effect of hydroxyethyl starch infusion on colloid oncotic pressure in hypoproteinemic horses

OBJECTIVE: To determine the effect of hydroxyethyl starch (HES) on colloid oncotic pressure (pi) during fluid resuscitation of hypoproteinemic horses and to evaluate the clinical usefulness of direct and indirect methods for determination of pi before and after infusion of a synthetic colloid. DESIGN: Prospective clinical study. ANIMALS: 11 hypoproteinemic horses. PROCEDURE: Horses received IV infusions of 8 to 10 ml of a 6% solution of HES/kg (3.6 to 4.5 ml/lb) of body weight during fluid resuscitation. Blood samples were obtained for determination of plasma measured colloid oncotic pressure (pi meas) and plasma total protein and albumin (A) concentrations. Plasma globulin concentration (G) was calculated as the difference between plasma total protein and albumin concentrations. Calculated values for colloid oncotic pressure (piA + G) were determined by use of a predictive nomogram previously developed for horses. RESULTS: There was no significant difference between the means of pi meas and piA + G at the beginning of HES infusion. After HES infusion, the mean of pi meas was increased significantly from baseline for 6 hours. Mean plasma total protein and albumin concentrations and piA + G were decreased significantly from baseline for 24 hours. Differences between mean pi meas and piA + G after HES infusion were significant for 24 hours. CONCLUSIONS AND CLINICAL RELEVANCE: There was good agreement between plasma pi meas and piA + G in blood samples obtained from hypoproteinemic horses immediately before infusion of HES. Use of a predictive nomogram did not, however, account for the oncotic effect of HES. Results of comparison of pi meas to piA + G after HES infusion suggest that a significant oncotic effect was maintained for 24 hours in the study horses.     

Gross and histopathological observations of long-term catheterized vessels in experimental sheep

Chronic indwelling central vessel catheters provide vascular access for compartmental infusion or sampling. However, complications with catheter patency during the postoperative and/or experimental period often arise. In order to identify physiological occurrences common with such complications, 10 multicatheterized sheep (61.8 +/- 7.8 kg BW), obtained from a previous nutrient flux study were used for gross and histopathological investigation. Catheters had been surgically placed in a hepatic portal vein (PVC), a hepatic vein (HVC), a distal mesenteric vein (MVC) and a mesenteric artery (MAC). In the previous study, catheters (PVC, HVC and MAC) were used to collect blood samples or infuse (MVC) p-aminohippurate. Catheters were maintained for a total of 58 days prior to necropsy. Histopathological findings indicated that catheter failures were associated with the following tissue responses: (i) thromboses with frequent focal vasculitis; (ii) euplastic tissues associated with extensive fibrosis; (iii) granulomas; (iv) neo-vascularization of the media; (v) calcification processes; and (vi) micro-abscesses. Additional studies are needed that address and incorporate improvement of catheter design and placement to minimize irritation of endothelium, improvement of catheter treatments and therapeutic regimes, and development and use of alternative anti-coagulants. A greater understanding of the mechanisms leading to failure will help researchers improve catheter performance and patency.     

Growth performance, carcass composition, quality, and enhancement treatment of fresh pork identified through deoxyribonucleic acid marker-assisted selection for the Rendement Napole gene

Progeny (n = 70) from unrelated, DNA tested, Rendement Napole carrier (RN-/rn+) Hampshire sires, and DNA tested, Rendement Napole normal (rn+/rn+) Yorkshire dams were genotyped for the segregating RN- allele via DNA marker-assisted methodology. Six slaughter groups ensued, with littermates all being represented within the same slaughter group. Boneless pork loins were removed from right carcass sides after a 48-h chill at 2 degrees C. The anterior portions of the loins were not enhanced, whereas the posterior sections were enhanced with a solution containing 0.5% sodium chloride and 0.5% sodium tripolyphosphate to 110% of their initial weight. Carcasses of carrier pigs had less (P < 0.05) 10th rib fat depth and a greater (P < 0.01) percentage carcass lean than carcasses of normal pigs. Postmortem LM pH of carrier pigs was lower (P < 0.002) at 3, 6, 12, and 24 h, and tended to be lower (P = 0.062) at 48 h compared with that of normal animals. Samples of LM from carrier pigs had greater (P < 0.01) glycolytic potential values, drip loss percentages, and a* values, and lower pH values at fabrication than LM from normal pigs. No genotype differences (P > 0.05) were found for LM lactate, L*, or b* values. Nonenhanced semimembranosus samples from carrier pigs exhibited greater (P < 0.05) purge loss percentages and L* values, and lower (P < 0.01) pH values than samples from normal pigs. Enhanced LM samples exhibited greater (P < 0.05) drip and purge loss percentages, greater pH, and lower L* values at fabrication, regardless of Napole status. These findings suggest that the Napole gene has a positive influence on carcass leanness but detrimental effects for lean quality, which were often further compounded when meat was subjected to enhancement treatment.     

冷季型草坪杂草综合防治技术与策略

冷季型草坪发展速度很快 ,但养护管理技术滞后 ,杂草危害严重。在调查掌握杂草的种类、数量及发生规律的情况下 ,应采取以下防治策略 :(1)严格杂草检疫制度 ,清洁播种材料 ;(2 )合理耕作 ,深埋杂草种子或幼苗 ,清洁坪床 ;(3)科学栽培管理 ,诱杀或抑制杂草 ,具体技术包括草种选择、播期、播量、施肥、浇水、修剪等 :(4)化学防除 ,具体包括播前诱杀除草 ,播后苗前和播后苗期除草     

Feed intake and serum GH, LH and cortisol in gilts after intracerebroventricular or intravenous injection of urocortin

In three experiments (Exp), ovariectomized gilts received intracerebroventricular (ICV; Exp 1 - with restraint, Exp 2 - without restraint) or intravenous (i.v.; Exp 3) injections of urocortin or saline to assess effects on feed intake and serum GH, LH, and cortisol. Following a 20-hr fast, feed was presented at 1 hr (Exp 1) or 30 min (Exp 2 and 3) after injection (time = 0 hr) of saline or 5 (U5) or 50 (U50) μg/pig (Exp 1 and 2) or 5 μg/kg BW (Exp 3) of urocortin. Blood samples were collected every 15 min from –2 to 6 hr relative to injection and hormone data pooled 2 hr before and hourly after treatment. Treatment with U50 decreased feed intake, relative to saline (treatment x time interaction; P < 0.05), when delivered ICV but not i.v. A treatment by time interaction was detected for GH (Exp 1, 2, 3) and LH (Exp 1 and 2; P < 0.01). Serum GH increased over time (relative to −2 hr; P < 0.05) following treatment with urocortin but not saline regardless of route of administration. Conversely, in Exp 1 (U5 and U50) and Exp 2 (U50), LH decreased relative to −2 hr with a delayed decrease during Exp 1. Serum cortisol was not affected by treatment in Exp 1, but increased following urocortin in Exp 2 and 3 (treatment by time interaction, P < 0.01). These data provide evidence that urocortin modulates GH and LH concentrations and suppresses feed intake in gilts via mechanisms which may be independent of cortisol and may depend upon dose and route of administration.     

Estimation of relationships between mineral concentration and fatty acid composition of longissimus muscle and beef palatability traits

The objective of this study was to determine the influence of beef LM nutrient components on beef palatability traits and evaluate the impact of USDA quality grade on beef palatability. Longissimus muscle samples from related Angus cattle (n = 1,737) were obtained and fabricated into steaks for trained sensory panel, Warner-Bratzler shear force (WBSF), lipid oxidation measured by thiobarbituric acid reactive substances (TBARS), fatty acid, and mineral composition analysis. Pearson phenotypic correlations were obtained by the correlation procedure of SAS. Beef palatability data were analyzed by the GLM procedure of SAS with USDA quality grade as the main effect. Specific mineral concentrations did not demonstrate strong correlations with WBSF or sensory traits (r = -0.14 to 0.16). However, minerals appeared to have a stronger relationship with flavor; all minerals evaluated except Ca and Mn were positively correlated (P < 0.05) with beef flavor. Stearic acid (C18:0), C18:2, C20:4, and PUFA were negatively correlated (P < 0.05) with all 3 panelist tenderness traits (r = -0.09 to -0.22) and were positively correlated (P < 0.05) with WBSF (r = 0.09 to 0.15). The MUFA were positively correlated (P < 0.05) with panelist tenderness ratings (r = 0.07 to 0.10) and negatively associated (P < 0.05) with WBSF (r = -0.11). The strongest correlations with juiciness were negative relationships (P < 0.05) with C18:2, C18:3, C20:4, and PUFA (r = -0.08 to -0.20). Correlations with beef flavor were weak, but the strongest was a positive relationship with MUFA (r = 0.13). Quality grade affected (P < 0.05) WBSF, TBARS, and all trained sensory panel traits, except livery/metallic flavor. As quality grade increased, steaks were more tender (P < 0.05), as evidenced by both WBSF and sensory panel tenderness ratings. Prime steaks were rated juiciest (P < 0.05) by panelists, whereas Select and Low Choice were similarly rated below Top Choice for sustained juiciness. Quality grade influenced (P < 0.05) beef flavor, but not in a linear fashion. Although there were significant correlations, these results indicate tenderness, juiciness, and flavor are not strongly influenced by individual nutrient components in beef LM. Furthermore, the positive linear relationships between USDA quality grade and beef palatability traits suggest quality grade is still one of the most valuable tools available to predict beef tenderness.