Chemometric discrimination among wild and cultured age-0 largemouth bass, black crappies, and white crappies based on fatty acid composition

The potential to distinguish juvenile wild from cultured fishes and to discriminate among juvenile fishes by species based on fatty acid composition was demonstrated. Statistical approaches to data evaluation included analysis of variance, correlation analysis, principal component analysis (PCA), and quadratic discriminant analysis (QDA). Differences were determined between wild and cultured fishes both within and between species and between hatcheries. Fatty acid compositions were compared among individual (not composited) specimens of wild and cultured, age-0, freshwater species: largemouth bass Micropterus salmoides, black crappies Pomoxis nigromaculatus, white crappies P. annularis, and black-nose crappies. Four fatty acids were investigated: linoleic acid (18:2n-6), linolenic acid (18:3n-3), arachidonic acid (20:4n-6), and docosahexaenoic acid (22:6n-3). Linoleic acid was the primary fatty acid used to differentiate juvenile wild from cultured fishes. Concentrations of linoleic acid were significantly different (p < 0.05) in cultured largemouth bass and black crappies from the wild counterparts. Linolenic acid concentrations were not significantly different (p < 0.05) between wild and cultured largemouth bass but were significantly different between wild and cultured black crappies. Wild largemouth bass contained higher concentrations of arachidonic acid than the cultured bass, and concentrations of docosahexaenoic acid were twice as high in wild black crappies than cultured black crappies. On the basis of four signature fatty acids, 90 of 91 juvenile fishes were correctly classified as wild or cultured; 32 of 37 wild juvenile fishes originating from the same reservoir were differentiated by species. Data from the training set were used to classify a test set of fishes as to species, source, or origin with 100% accuracy.     

Deposition and depletion of five anticoccidials in eggs

Anticoccidials are compounds that are widely used as feed additives to prevent and treat coccidiosis. They are licensed for use in a prescribed concentration and during a certain time interval for broilers and pullets but not for laying hens. It was shown in the past that carry-over at the feeding mill is found to be the main reason for the presence of residues in eggs. An animal experiment was set up to investigate the effect of carry-over at the feeding mill on the presence of residues of anticoccidials in eggs. For the compounds diclazuril, robenidine, halofuginone and nicarbazin in combination with narasin, two concentration levels were tested: the maximum allowed concentration for broilers (100%) and a concentration corresponding to 5% carry-over during feed preparation. Also dimetridazole was included in the experiment but only at one concentration level. Eggs were sampled during treatment (14 days) and for a period of 30 days after withdrawal of the anticoccidial-containing feed. Residues were determined, and deposition and depletion curves were generated. Analyses were performed by ELISA and LC-MS/MS. For all compounds, substantial residues could be found in the 5% groups, which points out the risk of carry-over at the feeding mill. The distribution of the residues between egg yolk and white was determined by analyzing both fractions.     

用CFD方法模拟日光温室温度环境初探

日光温室温度环境为一动态变化过程，该文建立了求解晴天室内温度环境的计算模型。将室外的水平面太阳辐照度、天空辐射温度、室外空气相对湿度、空气温度、风速及室内1.0m深土壤温度作为边界条件，采用计算流体动力学技术（CFD）中的非稳态方法求解控制方程，模拟了晴天室内温度随外界气候条件的变化，结果显示模拟得到的室内空气温度及土壤温度变化规律与实测值变化规律相同，盖帘后室内空气温度及土壤0.2 m深土层的温度模拟值与实测值相差约在1℃以内；探讨了边界条件中冷风渗透、土壤表面太阳能转换显热份额及1.0 m深土壤温度的取值变化对室内温度的影响。日光温室内温度动态变化模拟模型的建立对优化温室设计参数和预测不同天气情况下室内的温度环境变化具有参考意义。     

Fate and residues of [4-14C]estradiol-17 beta after intramuscular injection into Holstein steer calves

Radiocarbon-labeled estra-1,3,5(10)-triene-3,17 beta-diol [4-14C-estradiol-17 beta; beta-estradiol] was suspended in commercial peanut oil and administered to each of three Holstein steer calves (142 to 170 kg body weight) by deep injection into neck muscle via 2.0 ml peanut oil carrier. The dosages were equivalent to .27 to .29 mg beta-estradiol/kg body weight. After dosing, radiocarbon was rapidly and almost totally eliminated in urine and feces. Most of the administered radiocarbon had been eliminated after 2 d, and by 11 d after treatment no radiocarbon was detectable in urine or feces of any calf. Of the total dose, 42.1 +/- 3.8% was excreted in urine and 57.7 +/- 5.2% was eliminated in feces. Analysis of noninjection site tissue samples (blood, brain, fat, kidney, liver and muscle) collected at sacrifice 14 d after treatment showed that none contained detectable radiocarbon residues, with the sensitivity limit for most tissues being 6 ppb beta-estradiol equivalent. Certain sections of muscle taken from the injection site area did contain detectable radiocarbon residues (as much as 69 ppb beta-estradiol equivalent), but total injection site area residues in each calf comprised less than .07% of the total administered dose. Radiocarbon in urine consisted primarily of alpha-estradiol, with much lesser amounts of estrone. Both compounds occurred as nonconjugates and as glucuronides. beta-Estradiol was not detected in urine. Radiocarbon in feces included primarily alpha-estradiol but also beta-estradiol and estrone, each in non-conjugated form. The fact that most of the intramuscular-administered beta-estradiol was eliminated in the feces strongly suggests a major role for biliary excretion in the disposition of this steroid by steer calves.     

Paraneoplastic leukocytosis associated with a rectal adenomatous polyp in a dog.

A dog with a rectal adenomatous polyp had extreme neutrophilic leukocytosis, monocytosis, and eosinophilia consistent with a paraneoplastic syndrome. Resolution of the leukogram abnormalities after tumor excision supported this belief. Except for a lack of circulating myeloblasts, the dog had leukogram findings consistent with a neutrophilic leukemoid reaction.     

MAGNETIC RESONANCE IMAGING OF SPONGY DEGENERATION OF THE CENTRAL NERVOUS SYSTEM IN A LABRADOR RETRIEVER

A 7-month-old, neutered female Labrador Retriever was evaluated for tetraparesis and subtle cerebellar dysfunction. Clinical signs progressed over a period of 6 weeks to severe ataxia, hypermetria, intention tremors, and finally non-ambulatory tetraparesis. On magnetic resonance imaging of the brain there were large, bilaterally symmetrical, ovoid lesions in the region of the deep cerebellar nuclei that were hyperintense on T2-weighted and proton density images and hypointense on T1-weighted images. There were similar but smaller bilaterally symmetrical lesions present within the thalamus. Euthanasia was performed and lesions consistent with the previously described spongy degeneration of Labrador Retrievers were identified. This disease and its relation to similar human heritable leukodystrophies are discussed.     

THORACIC RADIOGRAPHY IN THE NEONATAL FOAL: A PRELIMINARY REPORT

Thoracic radiographs from 22 neonatal foals were reviewed to investigate the radiographic appearance of the thorax in normal, immature, and septicemic foals, and in foals with neonatal respiratory distress syndrome. The size and radiographic appearance of intrathoracic structures and abnormal lung opacities were evaluated. The craniocaudal and apicobasilar dimensions of the heart were 5.6–6.3 and 6.7–7.8 times the length of a midthoracic vetebral body, respectively, in normal, immature and septicemic foals. Apicobasilar measurements were greater (8.0–8.7) in the foals with respiratory distress syndrome. Normal foals had clear lung fields within 12 hours of birth. A more marked interstitial pattern was observed in immature and septicemic foals compared to normals. Diffuse air–space (alveolar) pattern with air bronchograms was seen in foals with respiratory distress syndrome. It was concluded from this series that thoracic radiographs taken 24–48 hours after birth may aid differentiation of normal foals, septicemic or immature foals, and foals with respiratory distress syndrome.     

Contact repellency of sheep blowfly Lucilia cuprina wied

The contact repellent effect of 24 new chemicals was assessed in a laboratory technique which used treated baits exposed to the sheep blowfly Lucilia cuprina Wied. The effect of some of the chemicals as antifeedants was also examined. An “Index of Repellency” and an “Index of Antifeedancy” were devised to give a reliable assessment of activity.