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1.
A destructive leaf spot disease was found onNymphaea alba in the lakes near Kortenhoef, Netherlands. After comparison of fresh material and herbarium specimens the causal agent is namedColletotrichum nymphaeae (Pass.) van der Aa, comb. nov. Synonymy, morphology and cultural characters of the fungus are described and discussed. Some remarks on the relationship with several host plants are given and the provisional conclusion is that the species is a widespread parasite, but that the destructive attack in the Kortenhoef region is probably caused by a combination of various factors.  相似文献   
2.
The original article to which this Correction refers was published in Pest Management Science 58 (7): 649–662 (2002).Copyright © 2004 Society of Chemical Industry  相似文献   
3.
The effect of organic phosphorus on metabolic, haematological and hormonal status, restoration of ovarian functions and conception rate in anoestrous Farafra ewes in subtropics were evaluated. Anoestrous Farafra ewes (n  = 24; 34.72 ± 0.52 kg body weight) were allocated into two equal groups: control and phosphorus groups. The ewes of phosphorus group were treated with sodium 4‐dimethylamino‐2‐methyl‐phenyl‐phosphonate as an organic bound phosphorous twice a week for successive 3 weeks. Ovarian follicle development and corpora lutea were checked three times a week till occurrence of oestrus using ultrasonography while pregnancy was confirmed at 30 days post‐service. Plasma metabolites, reproductive hormones, thyroid hormones and minerals were detected at weeks ?2, ?1, 0 (mating day) and + 4 weeks post‐oestrus. Phosphorus group had significantly (p  < .05) short interval to oestrous resumption if compared to control ewes (2.1 ± 0.8 weeks vs . 4.6 ± 1.1 weeks). In addition, phosphorous supplementation significantly (p  < .05) increased the number of antral follicles (developed and their sizes in addition to sizes of corpora lutea (8.72 ± 0.3 mm vs . 7.46 ± 0.9 mm) as well. Number of services per conception (2.6 vs . 1.4; p  < .01) was higher in control group than that of phosphorus group. Pregnancy rate (80 vs . 50%) was significantly (p  < .01) higher in phosphorus group when compared to control. White blood cells in treated ewes (10.8 ± 0.44; p  < .05) and monocytes (2.93 ± 0.13; p  < .01) were higher than that of control group (white blood cells; 9.53 ± 0.50 and monocytes; 2.24 ± 0.14). Metabolic parameters did not differ between phosphorus and control groups during different times of treatment. It could be concluded that phosphorous administration to anoestrous Farafra ewes in subtropics could improve reproductive performance and restore ovarian activity at the end of spring and early summer.  相似文献   
4.
Canola meal (CM) contains less crude protein (CP) and more fiber and anti-nutritional factors such as glucosinolates than soybean meal (SBM) and consequently has a lower nutrient digestibility. Therefore, processing strategies that may increase the feeding value of CM warrant study. In two experiments, the effects of extrusion of Brassica napus CM on apparent (AID) and standardized ileal digestibility (SID) of amino acids (AA), apparent total tract digestibility (ATTD) of gross energy (GE) in growing pigs, and growth performance and diet digestibility in weaned pigs were assessed. Solvent-extracted CM was extruded using a single-screw extruder at three screw speeds: 250 (CM-250), 350 (CM-350), or 450 (CM-450) rpm. In exp. 1, in a double 4 × 4 Latin square, eight ileal-cannulated barrows (initial body weight [BW], 68.1 kg) were fed corn starch-based diets containing 50% CM or extruded CM. The CM sample contained 43.2% CP, 33.2% total dietary fiber (TDF), and 8.9 µmol of total glucosinolates/g on a dry matter (DM) basis. Extrusion increased (P < 0.05) the AID of CP, reduced (P < 0.05) apparent hindgut fermentation of CP, and decreased (P < 0.05) predicted net energy (NE) value of diets. Extrusion increased diet AID and CM SID of most indispensable AA by 3.1 to 5.3%-units. In exp. 2, 200 weaned pigs (initial BW, 8.3 kg) were fed diets containing 20% SBM, CM, or extruded CM starting 2 wk postweaning for 3 wk. The CM sample contained 42.7% CP, 28.3% TDF, and 5.3 µmol total glucosinolates/g DM. Wheat-based diets provided 2.3 Mcal NE/kg and 5.1 g SID Lys/Mcal NE. Dietary inclusion of extruded CM replacing SBM decreased (P < 0.05) diet ATTD of DM, GE and CP, and DE value. Average daily feed intake, average daily gain (ADG), and gain:feed (G:F) of pigs did not differ between extruded CM and SBM diets and were not affected by extrusion, but increasing extruder screw speed linearly increased (P < 0.05) ADG for day 1 to 7 and G:F for the entire trial. In conclusion, extrusion increased diet AID and CM SID of AA but not DE and predicted NE values of CM. However, increasing extruder speed did not further increase the SID of most of the AA of CM in growing pigs. Dietary inclusion of 20% CM or extruded CM did not affect the growth performance in weaned pigs.  相似文献   
5.
Effect of energy and lysine intake in gestation on sow performance   总被引:2,自引:0,他引:2  
Nutrient intake during gestation has an impact on gestation parameters and subsequent lactation performance. The objectives of this experiment were to determine the impact of feeding two levels of amino acids in gestation on sow BW changes in gestation and lactation, and litter size, and to evaluate a factorial method for determining daily energy requirements. At mating, 419 sows (Camborough 15; Pig Improvement Canada, Acme, AB) were assigned randomly within Parities 1, 2 or 3+ to a gestation diet containing either 0.44% (low lysine) or 0.55% (high lysine) total lysine and 3,100 kcal DE/kg; other indispensable amino acids were adjusted to lysine based on ideal protein ratios. Feed allowance in gestation was determined factorially using estimated DE requirements for maintenance, maternal gain, and conceptus growth. Sows were allowed free access to the lactation diet. Gestation BW gain from d 0 to 110 was affected by parity (61.2, 60.0, and 42.3 kg for Parity 1, 2, and 3+, respectively; P < 0.05) but not (P > 0.10) by gestation lysine level. Sow BW changes from d 0 of lactation to weaning were affected by parity (0.5, 6.8, and 5.8 kg for Parity 1, 2, and 3+, respectively; P < 0.01) and gestation BW gain (P < 0.01), but not by gestation lysine level (5.0 vs 3.8 kg for low and high lysine, respectively; P > 0.10). Total piglets born was affected by parity (11.5, 12.1, and 12.5, for Parity 1, 2, and 3+, respectively; P < 0.01) and increased with increasing sow BW gain (P < 0.05). Total piglets born alive (mean = 11.2) was increased with increasing sow BW gain (P < 0.05). Total litter weight born alive was affected by parity (15.9, 18.6, and 19.4 kg for Parities 1, 2, and 3+, respectively; P < 0.01) and gestation BW gain (P < 0.05). The model used to determine daily energy intake requirements resulted in an average BW gain of 10.6 kg above the targets set by the model. Total lysine intakes greater than 10.6 g/d in gestation did not improve sow productivity. Setting target weight gains in gestation and feeding to meet these targets may not always provide predictable results due to a number of factors that affect the energy requirement in the sow.  相似文献   
6.
The objective of this study was to explore the possibility of producing wild buffalo embryos by interspecies somatic cell nuclear transfer (iSCNT) through handmade cloning using wild buffalo somatic cells and domestic buffalo (Bubalus bubalis) oocytes. Somatic cells derived from the ear skin of wild buffalo were found to express vimentin but not keratin and cytokeratin‐18, indicating that they were of fibroblast origin. The population doubling time of skin fibroblasts from wild buffalo was significantly (p < 0.05) higher, and the cell proliferation rate was significantly (p < 0.05) lower compared with that of skin fibroblasts from domestic buffalo. Neither the cleavage (92.6 ± 2.0% vs 92.8 ± 2.0%) nor the blastocyst rate (42.4 ± 2.4% vs 38.7 ± 2.8%) was significantly different between the intraspecies cloned embryos produced using skin fibroblasts from domestic buffalo and interspecies cloned embryos produced using skin fibroblasts from wild buffalo. However, the total cell number (TCN) was significantly (p < 0.05) lower (192.0 ± 25.6 vs 345.7 ± 42.2), and the apoptotic index was significantly (p < 0.05) higher (15.1 ± 3.1 vs 8.0 ± 1.4) for interspecies than that for intraspecies cloned embryos. Following vitrification in open‐pulled straws (OPS) and warming, although the cryosurvival rate of both types of cloned embryos, as indicated by their re‐expansion rate, was not significantly different (34.8 ± 1.5% vs 47.8 ± 7.8), the apoptotic index was significantly (p < 0.05) higher for vitrified–warmed interspecies than that for corresponding intraspecies cloned embryos (48.9 ± 7.2 vs 23.9 ± 2.8). The global level of H3K18ac was significantly (p < 0.05) lower in interspecies cloned embryos than that in intraspecies cloned embryos. The expression level of HDAC1, DNMT3a and CASPASE3 was significantly (p < 0.05) higher, that of P53 was significantly (p < 0.05) lower in interspecies than in intraspecies embryos, whereas that of DNMT1 was similar between the two types of embryos. In conclusion, these results demonstrate that wild buffalo embryos can be produced by iSCNT.  相似文献   
7.
Male camel infertility is a heterogeneous disorder. A variety of factors may adversely affect sperm production and function and impair fertility. This study was designed to evaluate the sensitivity and specificity of ultrasonography and testicular biopsy in the evaluation of the breeding soundness of male dromedaries compared with results obtained by clinical examination and semen analysis. Eighty‐four male dromedary camels (5–15 years old) were used in this study during the rutting season (November–May). Four sexually mature male camels were used as controls. These animals were apparently healthy and had histories of normal fertility. Eighty infertile male camels were subjected to an algorithmic approach based on information collected during careful examinations of the camels' breeding histories, clinical examinations, testicular evaluations, testicular ultrasonographies, the results of the semen analyses and testicular biopsies to diagnose the camels' infertilities. The differences in the semen parameters between the control and infertile male camels were highly significant (p < 0.01). Regarding the diagnoses of male camel infertility, the results of testicular ultrasonographies and biopsies were compared with those from the semen analyses, and the accuracies of these tests were 92.5% and 90%, respectively. Additionally, the results of the testicular ultrasonographies were matched with those of the testicular biopsies of the infertile animals, and this comparison resulted in 85% accuracy. Testicular biopsy is a promising method that, along with a carefully performed history, clinical examination, an appropriate testicular ultrasonography procedure and semen analysis, can afford veterinarians the opportunity for more precise diagnosis and treatment of many dromedary infertility disorders.  相似文献   
8.
Fermentation of cereal grains may degrade myo-inositol 1,2,3,4,5,6-hexakis (dihydrogen phosphate) (InsP6) thereby increasing nutrient digestibility. Effects of chemical acidification or fermentation with Limosilactobacillus (L.) reuteri with or without phytase of high β-glucan hull-less barley grain on apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of nutrients and gross energy (GE), standardized ileal digestibility (SID) of crude protein (CP) and amino acids (AAs), and standardized total tract digestibility (STTD) of P were assessed in growing pigs. Pigs were fed four mash barley-based diets balanced for water content: 1) unfermented barley (Control); 2) chemically acidified barley (ACD) with lactic acid and acidic acid (0.019 L/kg barley grain at a ratio of 4:1 [vol/vol]); 3) barley fermented with L. reuteri TMW 1.656 (Fermented without phytase); and 4) barley fermented with L. reuteri TMW 1.656 and phytase (Fermented with phytase; 500 FYT/kg barley grain). The acidification and fermentation treatments occurred for 24 h at 37 °C in a water bath. The four diets were fed to eight ileal-cannulated barrows (initial body weight [BW], 17.4 kg) for four 11-d periods in a double 4 × 4 Latin square. Barley grain InsP6 content of Control, ACD, Fermented without phytase, or Fermented with phytase was 1.12%, 0.59%, 0.52% dry matter (DM), or not detectable, respectively. Diet ATTD of DM, CP, Ca, and GE, digestible energy (DE), predicted net energy (NE) value, and urinary excretion of P were greater (P < 0.05) for ACD than Control. Diet ATTD of DM, CP, Ca, GE, DE and predicted NE value, urinary excretion of P was greater (P < 0.05), and diet AID of Ca and ATTD and STTD of P tended to be greater (P < 0.10) for Fermented without phytase than Control. Diet ATTD of GE was lower (P < 0.05) and diet ATTD and STTD of P, AID and ATTD of Ca was greater (P < 0.05) for Fermented with phytase than Fermented without phytase. Acidification or fermentation with/without phytase did not affect diet SID of CP and AA. In conclusion, ACD or Fermented without phytase partially degraded InsP6 in barley grain and increased diet ATTD of DM, CP, and GE, but not SID of CP and most AA in growing pigs. Fermentation with phytase entirely degraded InsP6 in barley grain and maximized P and Ca digestibility, thereby reducing the need to provide inorganic dietary P to meet P requirements of growing pigs.  相似文献   
9.
ObjectiveTo evaluate the effects of intravenous (IV) or intramuscular (IM) hyoscine premedication on physiologic variables following IV administration of medetomidine in horses.Study designRandomized, crossover experimental study.AnimalsEight healthy crossbred horses weighing 330 ± 39 kg and aged 7 ± 4 years.MethodsBaseline measurements of heart rate (HR), cardiac index (CI), respiratory rate, systemic vascular resistance (SVR), percentage of patients with second degree atrioventricular (2oAV) block, mean arterial pressure (MAP), pH, and arterial partial pressures of carbon dioxide (PaCO2) and oxygen (PaO2) were obtained 5 minutes before administration of IV hyoscine (0.14 mg kg?1; group HIV), IM hyoscine (0.3 mg kg?1; group HIM), or an equal volume of physiologic saline IV (group C). Five minutes later, medetomidine (7.5 μg kg?1) was administered IV and measurements were recorded at various time points for 130 minutes.ResultsMedetomidine induced bradycardia, 2oAV blocks and increased SVR immediately after administration, without significant changes in CI or MAP in C. Hyoscine administration induced tachycardia and hypertension, and decreased the percentage of 2oAV blocks induced by medetomidine. Peak HR and MAP were higher in HIV than HIM at 88 ± 18 beats minute?1 and 241 ± 37 mmHg versus 65 ± 16 beats minute?1 and 192 ± 38 mmHg, respectively. CI was increased significantly in HIV (p ≤ 0.05). Respiratory rate decreased significantly in all groups during the recording period. pH, PaCO2 and PaO2 were not significantly changed by administration of medetomidine with or without hyoscine.Conclusion and clinical relevanceHyoscine administered IV or IM before medetomidine in horses resulted in tachycardia and hypertension under the conditions of this study. The significance of these changes, and responses to other dose rates, requires further investigation.  相似文献   
10.
A number of insecticides used for ectoparasite control in the livestock industry were screened for their efficacy against larvae of the screw-worm fly, Chrysomya bezziana, using in vivo and laboratory tests. Proprietary screw-worm fly treatments (after exposure to outdoor conditions for up to 10 days) were also tested against eggs and adults of C bezziana. Three of these were also evaluated on naturally acquired screw-worm infestations. Residual protection was generally of short duration. Among the organophosphorus compounds, the most effective formulations contained relatively high concentrations (3 to 4% al) of coumaphos, 2.5% fenchlorphos or low concentrations (0.05 to 0.5% al) of diazinon, chlorfenvinphos and fenthion methyl. Two chlorinated hydrocarbon insecticides containing 3% lindane and 5% dieldrin were very effective but are now prohibited for use in Australia. Preparations had serious deficiencies when used under field conditions, especially for treating large, deepseated myiases for which systemic insecticides are recommended. A comparison of methods demonstrated that a laboratory test could supersede live animal experimentation, at least for the initial screening of potential insecticides.  相似文献   
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