肉鸡肿头综合征的病理形态学变化

对黑龙江省某鸡场发生肿头综合征（ Ｓ Ｈ Ｓ） 的４ 例肉鸡进行了病理学观察。肉眼所见为病鸡的眼周围、肉髯、肉冠的肿胀,包括肉髯、肉冠在内的头部皮下的蜂织炎,头盖骨气室内的干酪样物贮留。病理组织学所见主要为头部皮下组织、头盖骨气室及鼻粘膜下的纤维素性、化脓性肉芽肿性炎,并见有间质性心肌炎及支气管粘膜上皮组织纤毛脱落等变化。从上述病例的头部病灶中分离到了大肠杆菌。     

Effects of transportation during the hot season,breed and electrical stimulation on histochemical and meat quality characteristics of goat longissimus muscle

The effects of transportation and electrical stimulation (90 V) on physiological, histochemical and meat quality characteristics of two breeds of Omani goats were assessed. Twenty 1‐year‐old male goats from each breed (Batina and Dhofari) were divided into two groups: 3 h transported during the hot season (42°C day time temperature) and non‐transported. Animals were blood‐sampled before loading and prior to slaughter. Electrical stimulation was applied 20 min postmortem to 50% randomly selected carcasses of both breeds. Temperature and pH decline of the Longissimus was monitored. Ultimate pH, shear force, sarcomere length, myofibrillar fragmentation index, expressed juice, cooking loss and colour were measured from samples of Longissimus dorsi muscles. Electrical stimulation and transportation had a significant effect on most biochemical and meat quality characteristics of Longissimus dorsi. The transported goats had higher plasma cortisol (P < 0.01), adrenaline, nor‐adrenaline and dopamine concentrations (P < 0.05) than non‐transported goats. Electrical stimulation resulted in a significantly (P < 0.05) more rapid muscle pH fall during the first 12 h after slaughter. Muscles from electrically‐stimulated carcasses had significantly (P < 0.05) longer sarcomeres, lower shear force value, a lighter colour (higher L* value), higher expressed juice and myofibrillar fragmentation index than those from non‐stimulated ones. Meat from transported goats had significantly higher pH, expressed juice and shear force, but contained significantly lower sarcomere length and L* values than non‐transported goats. The proportion of the myosin ATPase staining did not change as a function of stimulation, transportation or breed. These results indicated that subjecting goats to transportation for 3 h under high ambient temperatures can generate major physiological and muscle metabolism responses. Electrical stimulation improved quality characteristics of meat from both groups. This indicates that electrical stimulation may reduce detrimental effects of transportation on meat quality of Omani goats.     

The red soils, their origin, properties, use and management in Greece

Red soils in Greece are distributed throughout the country, but they occur more frequently in the southern provinces and constitute important soil resources supporting several land utilization types. They can be grouped into two categories: the autochthonous and the allochthonous. The former soils are found on hard limestone and on basic igneous rocks in sloping mountainous or hilly landscapes. Moreover, they can be found on mica schists and gneisses in locations adjacent to marble or calcareous mica schists.Allochthonous red soils are wide-spread on late Tertiary and Pleistocene surfaces in the lowlands. Many of these deep deposits have red strata, a few decimeters to several meters thick, or red-colored and fine-textured layers interbedded with light colored deposits of marl, or conglomerates and also with thick strata enriched with calcareous concretions. They are distributed in the thermo- and meso-mediterranean bioclimatic zones. These sites have a common feature, the gently sloping terrain that ensures efficient drainage.There are some differences in chemical and physical properties and in the clay mineralogy of the two groups of Greek red soils. Palygorskite is present in some soils developed on basic rocks; the clay minerals of the allochthonous soils on Pleistocene and late Pliocene seems to be mixed with micas in significant amounts.Soil forming factors required for the formation of red soils are: (a) parent material containing iron-bearing minerals, and rich in bases, (b) slope gradients and/or water permeabilities of the bed-rock securing excessive drainage and (c) vegetation cover that does not produce high amounts of, and deeply distributed organic matter.The allochthonous red soils have likely inherited their color from their parent materials that were transported from the originally formed residual soils on hard limestone. The soils retain the red color in the thermo-mediterranean zone only on sloping terrains. The soils on these landscapes are frequently stratified.The Greek red soils belong to the great groups of: Rhodoxeralfs, Palexeralfs, Xerochrepts, Orthents. Large portions of the allochthonous soils have been desertified or have been severely degraded and their extensive exploitation is not recommended.Soil management practices applied in the allochthonous soils include erosion control, preservation of organic matter, minimum tillage, split application of nitrogen using non-acidifying fertilizers, irrigation, soil water conservation and sheltered agriculture.     

温室集约化生产系统对土壤质量的影响

Composite top- and subsoil samples were collected from the greenhouses in the Al-Balawneh area,Jordan,where intensive greenhouse production system（IGPS） has been practiced since 1998,to study the impact of IGPS on soil quality as measured by the chemical and biological properties to develop a sustainable production system.The study showed that IGPS led to higher electrical conductivity in top- and subsoils compared to an uncultivated soil（control）.Quality and amount of irrigation water,lack of efficient drainage,and quantity and types of applied fertilizers were major factors resulting in salt buildup.IGPS resulted in lower total N（TN） and NO₃-N in the soil compared to the control.The lower TN was due to crop uptake,microbial immobilization,volatilization,and irregular application of composted animal manure or poultry manure.In contrast,higher residual Olsen-P content was detected in both soil layers of greenhouses than in the control.Residual P was classified as very high in the topsoil layers and sufficient to high in the subsoil layers.Residual available K in the soils of greenhouses was relatively lower than that in the control and it was,however,classified as high to very high.A large increase of Cl and a considerable decrease in the bacterial count were observed in both soil layers of IGPS compared to the control treatment.Economically sustainable soil management practices need to be adopted by farmers to achieve a sustainable and profitable production.This can be accomplished through education,targeted towards the farming community in the central Jordan Valley.     

粤西地区三种不同土壤上的热带绿肥牧草引种试验

我国热带地区具有高温多雨、雨量分布不均匀且多暴雨的特点,容易引起水土流失,土壤有机质分解快,养分淋溶流失强烈,因此热带地区的红壤和砖红壤的有机质和速效养分含量都很低。热带经济林木和果园间种绿肥覆盖作物可以保持水土,增进地力,促使主作物速生高产^[1,2],而建立牧草基地以发展畜牧业和种植绿肥是增加优质有机肥料来源的有效途径。这样才有可能增施大量有机肥料,不断提高土壤肥力,保证农林作物稳产高产。     

Rock fragments I. Their effect on runoff, erosion and soil properties under field conditions

Abstract. The effects of different sizes, amounts, and positions of rock fragments on soil properties and erosion were studied in experimental plots (10 treatments including bare soils and soils under natural vegetation, with 3 replicates each) installed on a hillslope.
Over five events, the largest amounts of runoff were from bare soils containing abundant rock fragments, either partially embedded on the surface or incorporated in the upper part of the soil. Stoneless soils gave smaller amounts, and the smallest runoffs were measured on soils under natural vegetation. Generally, large rock fragments (cobbles) caused greater runoff than smaller fragments (coarse gravel). However, soils with appreciable amounts of coarse gravel on the surface generated considerable runoff under rainfalls of low intensity and long duration, but smaller amounts at greater rainfall intensities.
Sediment loss was greater from soils with cobbles than from soils containing coarse gravel; vegetation greatly decreased sediment loss from both.
In a 12-month period, the organic matter content of the soils decreased by 15.5 to 23.0%, decreasing soil aggregate stability. The organic matter content was greater in the collected sediments than in the soil.     

Yolk and serum cholesterol and production traits,as affected by incorporatinga supraoptimal amount of copper in the diet of the leghorn hen

1. An experiment was conducted to investigate the possibility of lowering the yolk cholesterol of the egg by supplementing the diet with supraoptimal amounts of copper (50, 150 or 250 mg/kg) as sulphate or acetate. 2. A significant reduction in egg production and a negative effect on food conversion was found when 250 mg/kg of copper was added compared to the control (no added copper). Acetate seemed significantly less harmful in both cases. 3. A significant linear reduction was found in plasma and yolk cholesterol (20% and 14%) and in plasma and yolk triglycerides (24% and 30%) as the dietary copper content was increased from 0 to 250 mg/kg. 4. Regardless of type or quantity of copper, cholesterol and lipids were decreased linearly as birds remained longer on the treatments. A significant interaction between quantity and period showed a greater reduction at a later time. 5. If slightly lower egg production can be accepted, the addition of 250 mg/kg copper might be beneficial in reducing the cholesterol content of the yolk.