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1.
Chase-Topping ME Gunn G Strachan WD Edwards SA Smith WJ Hillman K Stefopoulou SN Thomson JR 《Veterinary journal (London, England : 1997)》2007,173(2):353-360
The objective of this study was to investigate epidemiological risk factors for porcine non-specific colitis (NSC). Forty-seven Scottish pig farms, with and without a clinical history of diarrhoea during the growing period (15-40 kg), were selected. The study included farm visits, clinical inspection of pigs, completion of farm management questionnaires, pathological tests into the cause of the diarrhoea and analysis of the non-starch polysaccharide (NSP) content of feeds. The results from 17 farms designated as NSC and 10 control farms suggest dietary associations with NSC. Farms with NSC fed diets with significantly higher levels of NSPs, especially containing the sugars glucose, arabinose and xylose. Few management factors were identified, although the high prevalence of infectious colitis reduced the power of the study. 相似文献
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J. J. Almaraz F. Mabood X. Zhou I. Strachan B. Ma & D. L. Smith 《Journal of Agronomy and Crop Science》2009,195(5):319-327
Climate change will alter temperature and rainfall patterns over North American agricultural regions and there will be a need to adapt crop production systems to the altered conditions. A set of field experiments were conducted in south-western Quebec, Canada, with soybean ( Glycine max L.), corn ( Zea mays L.), sorghum ( Sorghum bicolor L.) × sudangrass ( Sorghum sudanense Piper) hybrid and switchgrass ( Panicum virgatum L.) under two tillage and three nitrogen fertility regimes, to study their performance in three successive growing seasons (2001–2003), two of them with unusually warm and dry conditions. The annual crops were established in two tillage systems: conventional and no-till (NT). All crops except soybean were fertilized with three levels of nitrogen: corn – 0, 90 and 180 kg N ha−1 , sorghum-sudangrass – 0, 75 and 150 kg N ha−1 , switchgrass – 0, 30 and 60 kg N ha−1 . The 2001 and 2002 seasons were hotter and drier than the 2003 season, which was the most favourable for crop growth. The capacity of the crops to yield in dry seasons was as follow: switchgrass > sorghum-sudangrass > corn > soybean. The corn and sorghum-sudangrass responses to nitrogen fertilizer were low in 2001 due to the combined effect of dry growing season and coarse soil texture. Soybean did not perform well under NT. Corn yielded better at the highest nitrogen fertilizer rate under NT when the early season was warmer than the normal. Our results show that switchgrass and sorghum-sudangrass could be an option in south-western Quebec if the frequency of hot and dry seasons increase in the future, because of climate change. 相似文献
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R Kasimanickam S Schroeder M Assay V Kasimanickam DA Moore JM Gay WD Whittier 《Reproduction in domestic animals》2014,49(5):775-782
The objectives were (i) to evaluate the effect of temperament, determined by modified 2‐point chute exit and gait score, on artificial insemination (AI) pregnancy rates in beef heifers following fixed time AI and (ii) to determine the effect of temperament on cortisol, substance‐P, prolactin and progesterone at initiation of synchronization and at the time of AI. Angus beef heifers (n = 967) at eight locations were included in this study. At the initiation of synchronization (Day 0 = initiation of synchronization), all heifers received a body condition score (BCS), and temperament score (0 = calm; slow exit and walk or 1 = excitable; fast exit or jump or trot or run). Blood samples were collected from a sub‐population of heifers (n = 86) at both synchronization initiation and the time of AI to determine the differences in serum progesterone, cortisol, prolactin and substance‐P concentrations between temperament groups. Heifers were synchronized with 5‐day CO‐Synch+ controlled internal drug release (CIDR) protocol and were inseminated at 56 h after CIDR removal. Heifers were examined for pregnancy by ultrasound 70 days after AI to determine AI pregnancy. Controlling for synchronization treatment (p = 0.03), facility design (p = 0.05), and cattle handling facility design by temperament score interaction (p = 0.02), the AI pregnancy differed between heifers with excitable and calm temperament (51.9% vs 60.3%; p = 0.01). The alley‐way with acute bends and turns, and long straight alley‐way had lower AI pregnancy rate than did the semicircular alley‐way (53.5%, 56.3% and 67.0% respectively; p = 0.05). The serum hormone concentrations differed significantly between different types of cattle handling facility (p < 0.05). The cattle handling facility design by temperament group interactions significantly influenced progesterone (p = 0.01), cortisol (p = 0.01), prolactin (p = 0.02) and substance‐P (p = 0.04) both at the initiation of synchronization and at the time of AI. Inter‐ and intra‐rater agreement for temperament scoring were moderate and good (Kappa = 0.596 ± 0.07 and 0.797 ± 0.11) respectively. The predictive value for calm and pregnant to AI was 0.87, and excited and non‐pregnant to AI was 0.76. In conclusion, the modified 2‐point temperament scoring method can be used to identify heifers with excitable temperament. Heifers with excitable temperament had lower AI pregnancy. Further, cattle handling facility design influenced the temperament and AI pregnancy. 相似文献
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John Gordon Bell Fiona Strachan Joanne E Good & Douglas R Tocher 《Aquaculture Research》2006,37(6):606-617
Echium oil (EO) is a vegetable oil in which percentages of stearidonic acid (STA, 18:4n‐3) often exceed those of its n‐6 series equivalent γ‐linolenic acid (GLA, 18:3n‐6). Stearidonic acid is elongated to 20:4n‐3 in fish cell cultures, suggesting that EO could be included in diets for marine fish to increase tissue 20:4n‐3 and 20:3n‐6 and, thereby, modulate eicosanoid metabolism. Thus, the present study aimed to test the hypotheses that dietary EO would increase tissue 20:4n‐3 and 20:3n‐6 and modulate immune function and eicosanoid production in juvenile Atlantic cod (Gadus morhua L.) fed a diet where fish oil (FO) was replaced by EO. Duplicate groups of juvenile cod (initial weight ca. 4 g) were fed for 18 weeks on fish meal‐based diets (55% protein and 16% lipid) that differed in oil source (FO or EO). There were no significant differences in growth and feed efficiency, hepato‐somatic index, percentages of liver and flesh lipids and lipid class compositions for cod fed FO and EO. Percentages of 18:4n‐3, 18:3n‐6 and 20:3n‐6 in the total lipids of flesh and liver were higher, and percentages of 20:5n‐3 and 20:4n‐6 were both lower in fish fed EO than in those given FO. In flesh, the increased 18:3n‐6 and 18:4n‐3 were primarily located in phosphatidylcholine and, to a lesser extent, phosphatidylethanolamine, whereas 20:3n‐6 concentration was highest in phosphatidylinositol. Desaturation of 18:3n‐3 (to tetraene products) and 20:5n‐3 to 22:6n‐3 in hepatocytes was very low but was increased by dietary EO. Echium oil significantly decreased the production of prostaglandin F from gill cells stimulated with calcium ionophore A23187, and reduced head kidney macrophage activity, but had no effect on serum lysozyme activity or basic haematology. In conclusion, dietary EO may have beneficial effects on some immune parameters including eicosanoid metabolism in marine fish although this may be primarily because of decreased 20:4n‐6 rather than increasing tissue levels of 20:3n‐6 or 20:4n‐3. 相似文献
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A counter for rapid counting of live fish, especially trout and salmon, has been developed. The response time of the counter is approximately 100 ms and hence a throughput of up to 10 000 fish per hour can be obtained. Results are given in the paper for counting fish of between 300 g and 1 kg with an error of less than ± 3%. 相似文献
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Dinitroaniline herbicides such as oryzalin (3,5-dinitro-N4,N4-dipropylsulfanilamide) disrupt mitosis in the meristematic cells of seedling plants by inhibiting the formation of microtubules. For further understanding of the biochemical mechanism of action of oryzalin, laboratory analyses with isolated plant tubulin must be employed. Plant tubulin from flagella of the alga Chlamydomonas was isolated and purified. This tubulin was incubated with [14C]oryzalin, and free oryzalin was separated from oryzalin bound to plant tubulin by miniature DEAE-cellulose chromatography. Scatchard analysis predicts a molar ratio of oryzalin bound to plant tubulin of 1.0 ± 0.1 when oryzalin is incubated with plant tubulin for 30 min at pH 6.9 and 25°C. The association constant for the oryzalin-tubulin complex is 2.08 ± 0.08 × 105M?1 at 25°C. The thermodynamic values for the formation of the oryzalin-tubulin complex at 25°C are ΔGo = ?7.25 ± 0.02 kcal mol?1, ΔHo = 6.5 ± 0.2 kcal mol?1, and ΔSo = 46 ± 2 cal mol?1 deg?1 (mean ± standard error). Oryzalin has little or no affinity for intact microtubules, previously denatured plant tubulin, actin, bovine serum albumin, calmodulin, ferredoxin, trypsin, or urease, indicating oryzalin is specific for the biologically active conformation of plant tubulin. Oryzalin binds to plant tubulin to form a complex that may be incapable of polymerizing into microtubules. 相似文献
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The incidence of dystocias and the calving performance of primiparous Hereford heifers from 2 herds, one with a low (A) and the other a high (B) dystocia history, were compared when all animals were run on the same property in southern Queensland.
The dystocia incidence was 21.4% for Herd A heifers and 40.5% for Herd B heifers (P≅0.10). While Herd A heifers had significantly (P<0.05) heavier calves than Herd B heifers (29.1 v 27.7 kg), the ratio of calf birth weight to dam pelvic brim area was 0.11 kg/cm2 for both groups. Differences in the size of the maternal pelvis, calf oversize and the type of presentation recorded for assisted births did not satisfactorily explain the difference in the incidence of dystocias. The circumstantial evidence indicated that inherent factors may affect dystocia. 相似文献
The dystocia incidence was 21.4% for Herd A heifers and 40.5% for Herd B heifers (P≅0.10). While Herd A heifers had significantly (P<0.05) heavier calves than Herd B heifers (29.1 v 27.7 kg), the ratio of calf birth weight to dam pelvic brim area was 0.11 kg/cm
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CASE HISTORY: A mature male tuatara was presented with a history of recurrent cloacal prolapse. CLINICAL AND PATHOLOGICAL FINDINGS: The prolapsed tissue included a 12 mm diameter mass, which histologically showed cords and nodules of neoplastic epithelial cells. DIAGNOSIS: The mass was diagnosed as a squamous cell carcinoma with ulceration of the overlying stratified squamous epithelium and diffuse inflammation of the surrounding dermis. CLINICAL RELEVANCE: This case presented a rare opportunity to investigate squamous cell carcinoma in a long-lived lower vertebrate species. Future recurrence or metastasis of the mass may add useful information to the current base of knowledge of the behaviour of malignant neoplasms in reptiles. 相似文献
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Abstract CASE HISTORY: A 13-year-old Thoroughbred mare was presented with a history of mild colic over 3 days. This colic had acutely exacerbated and was unresponsive to analgesic treatment, and was referred to Massey University Veterinary Teaching Hospital. CLINICAL FINDINGS: On examination the heart rate was 100 beats per minute, and mucous membranes were pale and tacky. A large mass was detected on transrectal palpation in the caudal abdomen to the left of midline. Explorative laparotomy revealed severe haemoperitoneum and several masses that were associated with the reproductive tract. The mare was then subject to euthanasia. On post-mortem examination, adjacent and attached to each ovary were soft, lobulated dark red masses up to 200 mm in diameter. Similar masses were present in the omentum and on the peritoneal surface of the diaphragm and the serosa of the spleen and liver. Histopathology revealed that the neoplastic component of the masses comprised proliferating cuboidal to columnar cells forming disorganised acini and cords separated by dense collagenous stroma. Immunohistochemistry showed the neoplastic cells were positive for cytokeratin AE1/AE3 and vimentin, but negative for cytokeratin 7 and inhibin α. DIAGNOSIS: Bilateral ovarian adenocarcinoma with transcoelomic metastasis and terminal decompensation due to rupture of a neoplastic mass and consequent haemoperitoneum. CLINICAL RELEVANCE: To the authors' knowledge, bilateral ovarian adenocarcinoma has not been previously reported in a horse. Ovarian adenocarcinoma should be considered when horses present with haemoperitoneum and colic. Further research is required on the immunohistochemical differentiation of adenocarcinoma of ovarian and intestinal origin in the horse. 相似文献