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71.
Objective To determine the effectiveness of a topical anaesthetic formulation (Tri-Solfen) with or without the administration of a non-steroidal anti-inflammatory drug (carprofen) on the pain and distress response associated with ring or surgical castration of ram lambs.
Procedures Merino ram lambs (n = 78) were allocated to 10 treatment groups: 4 groups of knife-castrated lambs and 4 groups of ring-castrated lambs received carprofen (4 mg/kg SC) and Tri-Solfen; 2 control groups (sham) received carprofen at 0 or 4 mg/kg SC. Measurements included plasma cortisol and haptoglobin concentrations, haematology, and behaviour, including posture.
Results Knife-castrated lambs had higher peak cortisol and integrated cortisol responses for the first 6 h after treatment and greater concentration s of circulating acute phase proteins than ring-castrated lambs, both of which were significantly different from the sham controls. Tri-Solfen applied to the knife castration wound significantly reduced both the peak plasma cortisol concentration and the integrated cortisol response for the first 6 h and improved lying behaviour in the first 12 h. Carprofen reduced the cortisol response to knife castration at 30 min, but elevated the cortisol responses at 24 and 48 h. Carprofen nearly halved the number of acute pain behaviours associated with ring castration. There were no significant additive or synergistic effects from combining the analgesic treatments. Tri-Solfen applied to the tail wound provided no detectible benefits during ring castration + tail docking.
Conclusions The physiological and behavioural responses suggest that ring castration has less impact on the lamb than knife castration. The specific analgesic treatments can provide modest amelioration of the pain and discomfort associated with castration. Alternative doses or application methods may enhance their efficacy. 相似文献
Procedures Merino ram lambs (n = 78) were allocated to 10 treatment groups: 4 groups of knife-castrated lambs and 4 groups of ring-castrated lambs received carprofen (4 mg/kg SC) and Tri-Solfen; 2 control groups (sham) received carprofen at 0 or 4 mg/kg SC. Measurements included plasma cortisol and haptoglobin concentrations, haematology, and behaviour, including posture.
Results Knife-castrated lambs had higher peak cortisol and integrated cortisol responses for the first 6 h after treatment and greater concentration s of circulating acute phase proteins than ring-castrated lambs, both of which were significantly different from the sham controls. Tri-Solfen applied to the knife castration wound significantly reduced both the peak plasma cortisol concentration and the integrated cortisol response for the first 6 h and improved lying behaviour in the first 12 h. Carprofen reduced the cortisol response to knife castration at 30 min, but elevated the cortisol responses at 24 and 48 h. Carprofen nearly halved the number of acute pain behaviours associated with ring castration. There were no significant additive or synergistic effects from combining the analgesic treatments. Tri-Solfen applied to the tail wound provided no detectible benefits during ring castration + tail docking.
Conclusions The physiological and behavioural responses suggest that ring castration has less impact on the lamb than knife castration. The specific analgesic treatments can provide modest amelioration of the pain and discomfort associated with castration. Alternative doses or application methods may enhance their efficacy. 相似文献
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Jamie R. V. Sookhoo Arianne Brown-Jordan Lemar Blake Ridley B. Holder Sharon M. Brookes Stephen Essen Christine V. F. Carrington Ian H. Brown Christopher A. L. Oura 《Tropical animal health and production》2017,49(6):1117-1124
The objective of this study was to evaluate the seroprevalence and identify the strains of swine influenza virus (SwIV), as well as the seroprevalence of porcine parvovirus (PPV), transmissible gastroenteritis virus (TGEV), porcine reproductive and respiratory syndrome virus (PRRSV), porcine respiratory coronavirus (PRCV), porcine circovirus type 2 (PCV-2), and classical swine fever virus (CSFV) in pigs in Trinidad and Tobago (T&T). Blood samples (309) were randomly collected from pigs at farms throughout T&T. Serum samples were tested for the presence of antibodies to the aforementioned viruses using commercial ELISA kits, and the circulating strains of SwIV were identified by the hemagglutination inhibition test (HIT). Antibodies against SwIV were detected in 114 out of the 309 samples (37%). Out of a total of 26 farms, 14 tested positive for SwIV antibodies. HI testing revealed high titers against the A/sw/Minnesota/593/99 H3N2 strain and the pH1N1 2009 pandemic strain. Antibodies against PPV were detected in 87 out of the 309 samples (28%), with 11 out of 26 farms testing positive for PPV antibodies. Antibodies against PCV-2 were detected in 205 out of the 309 samples tested (66%), with 25 out of the 26 farms testing positive for PCV-2 antibodies. No antibodies were detected in any of the tested pigs to PRRSV, TGEV, PRCV, or CSFV. 相似文献
74.
Raffaele S Farrer RA Cano LM Studholme DJ MacLean D Thines M Jiang RH Zody MC Kunjeti SG Donofrio NM Meyers BC Nusbaum C Kamoun S 《Science (New York, N.Y.)》2010,330(6010):1540-1543
Many plant pathogens, including those in the lineage of the Irish potato famine organism Phytophthora infestans, evolve by host jumps followed by specialization. However, how host jumps affect genome evolution remains largely unknown. To determine the patterns of sequence variation in the P. infestans lineage, we resequenced six genomes of four sister species. This revealed uneven evolutionary rates across genomes with genes in repeat-rich regions showing higher rates of structural polymorphisms and positive selection. These loci are enriched in genes induced in planta, implicating host adaptation in genome evolution. Unexpectedly, genes involved in epigenetic processes formed another class of rapidly evolving residents of the gene-sparse regions. These results demonstrate that dynamic repeat-rich genome compartments underpin accelerated gene evolution following host jumps in this pathogen lineage. 相似文献
75.
J. S. Kamboj G. Browning J. D. Quinlan P. S. Blake D. A. Baker 《The Journal of Horticultural Science and Biotechnology》2013,88(5):773-780
SummaryThe polar transport of [3H]-indole-3-acetic acid in apical shoot segments of clonal apple rootstocks (M.27, M.9, M.26, MM.111 and MM.104) was investigated in the UK using a donor-receptor system. The month in which the experiment was undertaken had a significant influence on the uptake and transport of [3H]-indole-3-acetic acid activity; uptake and transport were greater in June and July (faster extension growth period) than in August (slower extension growth period). Shoot segments from dwarfing rootstocks (M.27 and M.9) showed smaller uptake and less transport of [3H]-indole-3-acetic acid than those from invigorating rootstocks (MM.111 and MM.104). [3H]-indole-3-acetic acid was transported to the agar receptors through shoot segments from all the rootstocks in June and July; those from dwarfing rootstocks showing lower levels of transport than those from invigorating ones. However, in August, [3H]-indole-3-acetic acid activity from the agar receptors was detected only from shoot segments of invigorating rootstocks, which continued to produce extension growth slowly, when dwarfing rootstocks had already ceased shoot extension growth. These results are discussed with reference to the effects of apple rootstocks on the size of scions. 相似文献
76.
Blake Troxel Max Piana Mark S. Ashton Colleen Murphy-Dunning 《Urban Forestry & Urban Greening》2013,12(2):144-153
Knowledge of allometric equations can enable urban forest managers to meet desired economic, social, and ecological goals. However, there remains limited regional data on young tree growth within the urban landscape. The objective of this study is to address this research gap and examine interactions between age, bole size and crown dimensions of young urban trees in New Haven, CT, USA to identify allometric relationships and generate predictive growth equations useful for the region. This study examines the 10 most common species from a census of 1474 community planted trees (ages 4–16). Regressions were applied to relate diameter at breast height (dbh), age (years since transplanting), tree height, crown diameter and crown volume. Across all ten species each allometric relationship was statistically (p < 0.001) significant at an α-level of 0.05. Consistently, shade trees demonstrated stronger relationships than ornamental trees. Crown diameter and dbh displayed the strongest fit with eight of the ten species having an R2 > 0.70. Crown volume exhibited a good fit for each of the shade tree species (R2 > 0.85), while the coefficients of determination for the ornamentals varied (0.38 < R2 < 0.73). In the model predicting height from dbh, ornamentals displayed the lowest R2 (0.33 < R2 < 0.55) while shade trees represented a much better fit (R2 > 0.66). Allometric relationships can be used to develop spacing guidelines for commonly planted urban trees. These correlations will better equip forest managers to predict the growth of urban trees, thereby improving the management and maintenance of New England's urban forests. 相似文献
77.
78.
Objective To develop a lameness model to assess the efficacy of analgesics for alleviating pain, swelling and systemic signs of inflammation in sheep. Procedures The response to subcutaneous injection of 0.1 or 0.2 mL turpentine in a forelimb pastern (n = 4 ewes per dose) was examined at 0, 3, 6, 24, 48 and 72 h. In a second experiment, responses were measured at 0, 2, 4, 6, 8, 10, 12 and 24 h in ewes receiving 0.1 mL turpentine ± meloxicam 1 mg/kg IV at 0 h (n = 6 per group). Responses measured included forceplate pressure, skin temperature, limb circumference, nociception, leucocyte count, neutrophil : lymphocyte ratio, haptoglobin and daily feed intake. Results Turpentine injection caused a decrease in weight borne on the treated limb, increased skin temperature, increased sensitivity at the injection site and leucocytosis by 2 h and increased limb circumference by 4 h. Weight borne and sensitivity of the injected limb returned to control levels after around 24 h, whereas tissue swelling, elevated skin temperature and elevated haptoglobin levels persisted for at least 72 h. Treatment with meloxicam improved weight borne by and tolerance to pressure exerted on the turpentine‐injected limb. Conclusions The local and systemic signs of inflammation and pain, temporary reduction in function of the affected limb and partial amelioration of some of these changes by the dose of meloxicam used here suggest that injection of turpentine in the lower forelimb provides a suitable model for examining the efficacy of analgesics for alleviation of pain and inflammation in sheep. 相似文献
79.
Background
The objective of this study was to describe aspects of case study herds investigated by the Department of Agriculture, Fisheries and Food (DAFF) in which animal welfare incidents occurred and to identify key performance indicators (KPIs) that can be monitored to enhance the Early Warning System (EWS). Despite an EWS being in place for a number of years, animal welfare incidents continue to occur. Questionnaires regarding welfare incidents were sent to Superintending Veterinary Inspectors (SVIs), resulting in 18 herds being chosen as case study herds, 12 of which had a clearly defined welfare incident date. For each study herd, data on six potential KPIs were extracted from DAFF databases. The KPIs for those herds with a clearly defined welfare incident date were studied for a consecutive four year window, with the fourth year being the ''incident year'', when the welfare incident was disclosed. For study herds without a clearly defined welfare incident date, the KPIs were determined on a yearly basis between 2001 and 2009.Results
We found that the late registration of calves, the use of on-farm burial as a method of carcase disposal, an increasing number of moves to knackeries over time and records of animals moved to ''herd unknown'' were notable on the case farms.Conclusion
Four KPIs were prominent on the case study farms and warrant further investigation in control herds to determine their potential to provide a framework for refining current systems of early warning and prevention. 相似文献80.
Rachel Pilla Frederic P. Gaschen James W. Barr Erin Olson Julia Honneffer Blake C. Guard Amanda B. Blake Dean Villanueva Mohammad R. Khattab Mustafa K. AlShawaqfeh Jonathan A. Lidbury Jörg M. Steiner Jan S. Suchodolski 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2020,34(5):1853-1866