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11.
In order to provide a consistent system for laboratory production of embryos, the characteristics of immature camel oocyte must first be described. The objective of this study was to define ultrastructural features of immature camel oocyte. Ovaries were obtained from camels at a local abattoir, and then transported to the laboratory within 2 h. Camelus cumulus oocyte complexes (COCs) were aspirated from 2-6 mm follicles using a 22-gauge needle. Excellent and good quality COCs were selected and prepared for transmission electron microscopy study using a cavity slide. The fine structure of camel oocyte is morphologically similar to that of other mammalian oocytes. However, some minor differences exist between COC of camel and other mammalian species. Different size and shape of membrane-bound vesicles, lipid droplet, mitochondria and cortical granules were distributed throughout the ooplasm. Discrete or in association with endoplasmic reticulum, Golgi complexes were observed in the periphery of the oocytes. The majority of the oocytes were in the germinal vesicle stage.  相似文献   
12.
The aim of this study was to use radiography to assess and characterise naturally occurring keel bone fractures in laying hens and monitor live birds over several weeks to examine the healing process. Twenty-four Lohmann brown commercial laying hens with varying degrees of keel bone fracture were used in the study. Birds were radiographed regularly over six weeks and the radiographic features and changing appearance of keel bone fractures were evaluated. The radiographic characteristics of old and new fractures were categorised and indicated that 80 per cent of birds entering the study with new fractures had healed after 35 days and five birds had incurred new fractures irrespective of their original fracture status.  相似文献   
13.
Seeds of many woody plant species have one of several types of dormancy. They do not germinate unless specific environmental signals are in place or events occur. This study was conducted to evaluate the effects of scarification treatments on seed dormancy and germination of Acacia nilotica (L.) Willd. ex Del., Prosopis juliflora (Sw.) DC. and Dodonaea viscosa (L.) Jacq. The following treatments were applied: T1, untreated seed (control); T2, sulphuric acid (97%) for 45 min; T3, boiling water for 5 min. The seeds were cultured on a Murashige and Skoog (MS) medium after sterilization. The responses of seeds to treatments were compared with each other and with the control treatment. Germination was observed daily for a 30-day period. Results indicated positive responses to treatments, while impermeable seed coats may be responsible for low germination rates in intact seeds as seen experimentally in the untreated control. The highest germination was obtained for P. juliflora and D. viscosa acid-scarified seeds (80.8%-90.8%) and for scarified seeds of A. nilotica (50.2%) boiled in water. The germination indices, i.e., final germination percentage (FG), mean daily germination (MDG) and germination rate (GR), were significantly affected by treatments and species (p<0.01).  相似文献   
14.
The effect of stratification for 2–4 weeks and gibberellic acid (100 and 200 ppm) on germination of seeds and on total plant height was studied. The treatments resulted in earlier germination of seeds. The % germination was remarkably increased and stratification for 4 weeks followed by a 24-h soak in 100 ppm gibberellic acid solution gave the highest % germination.Total plant height was increased by the treatments and the effect was more profound when the seeds were stratified for 4 weeks followed by a 24-h soak in 200 ppm gibberellic acid solution.  相似文献   
15.
1. The impact of keel bone fractures on egg production, egg weight and feed and water consumption in individual laying hens. A total of 165 Lohmann brown laying hens were obtained from a commercial farm that consisted of 105 with keel fractures and 60 without keel fractures.

2. After a 4-d period of acclimatisation, hens were individually housed and provided with ad libitum food and water for a 24-h period. The number of eggs laid, egg weight, feed and water consumption during this period were recorded. Keel bone strength was also assessed.

3. Hens free from keel fractures laid more eggs (91.7% vs. 84.9%) of significantly heavier weight (61.9 g vs. 60.2 g), ate less feed (139 g vs. 151 g) and drank less water (212 ml vs. 237 ml) than hens with fractures.

4. There was a significant positive association between keel fracture severity and water consumption, and a significant negative association between keel fracture severity and egg weight and keel bone strength.

5. This small-scale study on individual birds shows that keel bone fractures may have an impact on the economics of egg production.  相似文献   

16.
17.
WorldFish initiated a selective breeding program in Abbassa—Egypt to develop and produce the genetically improved Nile tilapia strain known as “Genetically Improved Abbassa Nile tilapia (GIANT)”, adopting the same technology used for the Genetically Improved Farmed Tilapia (GIFT), in Asia. WorldFish provided the Ninth Generation (G9) broodstock of the GIANT to 11 Broodstock Multiplication Centers (BMC’s) in five governorates; these centres then disseminated improved mixed‐sex fry to 160 tilapia hatcheries which supplied all‐male fry to 1,500 fish farms in 2017. We present results of an impact assessment of the G9 of GIANT in 83 of these fish farms in four Egyptian governorates (Kafr El‐Sheikh, Fayoum, Behera and Alexandria). Results indicate that the use of GIANT in all governorates achieved significantly higher (18.8%) fish yields (12.3%–26.4%) and 15.7% lower FCR (feed conversion ratio), reflecting a positive impact on their net profits compared with those who used commercial strains. Overall, fish farmers who stocked GIANT had significantly higher average fish sales (5,567 US$/ha) than those who stocked non‐improved commercial strains (5,192 US$/ha) in all governorates. However, when comparing within governorates, the difference was significant only in Fayoum and Alexandria noting a mixed performance of the GIANT strain. The mixed performance indicates that some hatcheries may have crossed the different strains, which lowered the performance differences. To get an objective analysis of the performance of the GIANT, it is recommended that similar assessment be undertaken with new generations of the strain supported by on‐farm performance trials.  相似文献   
18.
The effects of combinations of salinity (no salt, 2000 p.p.m. or 4000 p.p.m. of CaCl2 and NaCl, 1:1) and water table (30 cm, 60 cm or 90 cm from the soil surface), on the vegetative growth and tolerance of ‘Golden Japanese’ plum and ‘Mit Ghamre’ and ‘Balady’ peaches were studied. The plants were grown in lysimeters. The growth of the trunk, total shoot length, the increase in shoot length per cm and the fresh weight of top, root and total plant were reduced with increasing salinity of the irrigation water. The effect was accentuated when the plants were maintained at high water table level. The salinity treatments resulted in the death of 43%, 73% and 76% of the plants in the plum, and the ‘Mit Ghamre’ and ‘Balady’ peaches, respectively, indicating that the plum is more tolerant to salinity than the peach. The plants of the salinity treatments showed various symptoms of salt injury, such as leaf burn, defoliation, shoot die-back and finally death. In the peaches, salt injury started to occur in the first growing-season, whereas the salt injury appeared in the plum in the second growing-season. The symptoms were more pronounced in the 4000 p.p.m. treatment than in the 2000 p.p.m. treatment and were more pronounced at the high water table level. The salinity level was the predominant factor and the effect of the water table on the vegetative growth diminished with increase in the salinity level of the irrigation water.  相似文献   
19.
Laboratory bioassay of the two fungiMetarbizium anisopliae (Metschnikoff) Sorokin andVerticillium indicum (Petch) Gams was carried out under 26±1 C° and 75±2% R. H. This is the first study on the efficiency of both mycopathogens against the termiteCryptotermes brevis (Walker). Using the highest concentration ofM. anisopliae (43.5 × 105 V.S/ml), percentages of mortality after 4 weeks from treatment of the termiteC. brevis fed on filter paper or wood were 100 and 93.33, respectively. On the same time, the highest concentration of the fungiV. indicum (34.3 × 105 V.S/ml) resulted in the mortality percentages of 83.33 and 70, respectively, fed on filter paper and wood. In general, the data indicated more susceptibility of the termiteC. brevis to the entomopathogenic fungusM. anisopliae than to the fungusV. indicum. M. anisopliae could be considered as a promising potential mycopathogen against the termiteC. brevis. This study, presenting new approach of the alternative dry wood termite control, might be applied in the future.  相似文献   
20.
Tropical Animal Health and Production - The effect of multinutrient antioxidant treatment on sheep naturally infected with FMD virus was investigated in terms of general health conditions, serum...  相似文献   
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