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61.
62.
Mogens Vestergaard Kristen Sejrsen John Foldager Signe Klastrup Dale E. Bauman 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(3):165-172
Abstract Our objective was to examine the effects of bovine growth hormone (bGH) on growth, carcass composition and meat quality of dairy heifers. Nine monozygotic twin pairs of Friesian or Red Danish cattle were used, and pair-fed à diet consisting of grass silage, barley and soybean meal. Within each pair, one animal was given daily subcutaneous injections of 20 IU of pituitary-derived bGH (15–20 mg), while the other animal was injected with saline (excipient). Treatments started at 179±2 kg body weight and lasted for 15.6 weeks. At slaughter, carcass composition and meat quality were analyzed. bGH treatment increased gain by 8% (948 vs. 877 g/d; P <0.03). The amount of saleable meat in carcass and lean content of four main carcass cuts were on average increased by 2% (P <0.05). Concomitantly, carcass fat trim was reduced by 12% (P <0.001), fat trim of individual cuts by 4–21% (P <0.05), and kidney fat by 13% (P <0.01). Except for a 20% reduction of intramuscular fat content (P <0.001), meat quality assessed by objective as well as subjective methods was unaffected by bGH treatment. In summary, bGH treatment of dairy heifers around puberty stimulated growth and reduced carcass fattening including intramuscular fat, while eating quality of the meat was unaffected. 相似文献
63.
Marie J. Hopfensperger Kristen M. Messenger Mark G. Papich Barbara L. Sherman 《Journal of Veterinary Behavior: Clinical Applications and Research》2013,8(3):114-123
Safe and humane handling in the veterinary clinic can be challenging when dealing with fearful or anxious dogs. Historically, alpha-2 adrenergic agonists have been used via parenteral routes to facilitate handling of difficult canine subjects. Detomidine hydrochloride is an alpha-2 agonist sedative commercially available in an oral transmucosal (OTM) formulation (Dormosedan Gel; Pfizer Animal Health, Madison, NJ) approved for sedation and restraint in horses. The usefulness of this detomidine formulation has not been previously reported in dogs. This study evaluated the behavioral and physiological effects of OTM detomidine gel administration in dogs to assess its efficacy and safety for facilitation of handling canine subjects. Six healthy institution-owned adult dogs were administered detomidine gel at a dose of 0.35 mg/m2 via OTM route. Behavioral and physiological assessments were performed pretreatment and repeated every 15–30 minutes for 5 hours after administration. Behavioral assessments included global sedation (GS), composite sedation (CS), global anxiolysis (GA), and ease of handling (EH) scores. Physiological assessments included heart rate and rhythm, respiratory rate, mucous membrane color, indirect blood pressure, rectal temperature, oxygen saturation, and capillary refill time. Posttreatment GS, CS, GA, and EH scores were improved for all 6 subjects as compared with pretreatment. For 4 of 6 dogs, maximal GS scores occurred at 45 minutes posttreatment, and duration of maximal GS scores was 30 minutes. Five of 6 dogs achieved adequate GS scores. EH scores were significantly higher during time points of adequate GS scores as compared with time points when adequate GS scores were not achieved. The physiological measures revealed transient bradycardia in 5 of 6 dogs and intermittent second-degree atrioventricular block in 1 dog. No other significant adverse events were noted, and all dogs recovered uneventfully. OTM detomidine gel was safely administered to 6 dogs at a dose of 0.35 mg/m2 and resulted in measurable sedation, anxiolysis, and improved EH in all subjects. Although further evaluation is warranted for use in client-owned dogs, OTM detomidine gel offers a novel sedative and anxiolytic option to facilitate handling of canine subjects. 相似文献
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Joseph Mascaro Kristen K. Becklund R. Flint Hughes Stefan A. Schnitzer 《Forest Ecology and Management》2008,256(4):593-606
Ecological invasions are a major driver of global environmental change. When invasions are frequent and prolonged, exotic species can become dominant and ultimately create novel ecosystem types. These ecosystems are now widespread globally. Recent evidence from Puerto Rico suggests that exotic-dominated forests can provide suitable regeneration sites for native species and promote native species abundance, but this pattern has been little explored elsewhere. We surveyed 46 sites in Hawai’i to determine whether native species occurred in the understories of exotic-dominated forests. Native trees smaller than 10 cm in diameter were absent in 28 of the 46 sites and rare in the others. Natives were never the dominant understory species; in fact, they accounted for less than 10% of understory basal area at all but six sites, and less than 4% on average. Sites with native species in the understory tended to be on young lava substrate lacking human disturbance, and were mostly located close to intact, native-dominated forest stands. Even where we found some native species, however, most were survivors of past exotic encroachment into native forest, rather than products of active recolonization by native species. In contrast with successional trajectories in Puerto Rico, Hawaii's exotic-dominated forests can emerge, via invasion, without human disturbance and native Hawaiian plants are largely unable to colonize them once they appear. We suggest that a wide diversity of growth strategies among the exotic species on Hawai’i may limit the opportunities for native plants to colonize exotic-dominated forests. 相似文献
66.
Coast redwood (Sequoia sempervirens) and tanoak (Lithocarpus densiflorus) form mixed-evergreen forests along the northern California coast. In the mid-1990s, an introduced pathogen (Phytophthora ramorum) began causing extensive mortality of tanoak in these forests. This research reconstructed stand development patterns occurring in stands with and without the pathogen, measured stand responses to tanoak mortality, and developed projections of future stand development and structure in the presence of P. ramorum. Redwood forms an upper canopy layer while tanoak forms a multicohort lower canopy, resulting in distinct vertical stratification patterns. Individual redwood tree response patterns to tanoak mortality included crown expansion, increased basal sprouting, and increased basal area growth. Future stand structures will likely have greater proportions of redwood relative to tanoak. 相似文献
67.
68.
Nicole Pacifico DVM Kristen M. Weishaar DVM Lindsay B. Boozer DVM Reid K. Nakamura DVM DACVECC 《Journal of Veterinary Emergency and Critical Care》2010,20(2):264-267
Objective – To describe the successful management of cardiac arrest following accidental venous air embolism (VAE) in a cat. Case Summary – A 3‐year‐old spayed female domestic shorthair cat, weighing 4 kg, was presented for continuation of its chemotherapy protocol. The cat was inadvertently administered approximately 5.5 mL of air IV during initiation of fluid therapy. Immediate cardiac arrest resulted and CPR successfully achieved return of spontaneous circulation. The cat was discharged 5 days later and is reportedly clinically normal 7 months post‐discharge. New or Unique Information Provided – VAE has been rarely reported in the veterinary literature. This is the first report of a cat surviving cardiac arrest secondary to VAE. 相似文献
69.
Kennison KR Gibberd MR Pollnitz AP Wilkinson KL 《Journal of agricultural and food chemistry》2008,56(16):7379-7383
The release of smoke-derived volatile phenols during the fermentation of Merlot grapes, following grapevine exposure to smoke, has been investigated. The concentrations of guaiacol, 4-methylguaiacol, 4-ethylguaiacol, 4-ethylphenol, and eugenol were determined by gas chromatography-mass spectrometry and found to increase throughout the winemaking process. Only trace levels (< or = 1 microg/L) of guaiacol and 4-methylguaiacol could be detected in free run juice derived from the fruit of smoked vines; the highest levels, 388 microg/L and 93 microg/L, respectively, were observed in the finished wine. Control wine (derived from fruit of unsmoked vines) contained 4 microg/L guaiacol, with the volatile phenols either not detected or detected at only trace levels (< or = 1 microg/L) throughout fermentation. The role of enzyme and acid catalyzed hydrolysis reactions in releasing smoke-derived volatile compounds was also investigated. The volatile phenols were released from smoked free run juice by strong acid hydrolysis (pH 1.0) and enzyme (beta-glucosidase) hydrolysis, but not mild acid hydrolysis (juice pH 3.2-3.7). Guaiacol was again the most abundant smoke-derived phenol, present at 431 microg/L and 325 microg/L in strong acid and enzyme hydrolysates, respectively. Only trace levels of each phenol could be detected in each control hydrolysate. This study demonstrates the potential for under-estimation of smoke taint in fruit and juice samples; the implications for the assessment of smoke taint and quantification of volatile phenols are discussed. 相似文献
70.
Woosley KP 《Clinical Techniques in Small Animal Practice》2004,19(1):43-48
Normal gastrointestinal motility is crucial for maintaining an appropriate balance of microorganisms within the gut. Disruption of this system results in bacterial overgrowth and associated complications such as bacterial translocation, aspiration pneumonia, and sepsis. Critically ill animals are at increased risk of developing gastroparesis caused by primary gastrointestinal disturbances or severe metabolic derangements that impact gastrointestinal function. In the intensive-care setting, delayed gastric emptying complicates enteral nutrition, and the catabolic effects of severe illness further deplete the patient's caloric reserves, resulting in impaired wound healing, decreased immune function, and increased morbidity and mortality. The use of promotility drugs in critically ill patients is a safe, effective means to circumvent the problem of gastric atony and improve patient recovery. Understanding the drugs available and their interaction with the receptors involved in neuromuscular transmission within the gastrointestinal tract will aid the clinician in selecting the optimal prokinetic therapy. 相似文献