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221.
Although Brachiaria decumbens was not toxic when fed to cattle, the infusion of rumen liquor from B. decumbens intoxicated sheep into the rumen of cattle produced evidence suggesting hepatic and renal dysfunction. Several biochemical changes were observed including increases in serum aspartate amino transferase, serum creatinine and blood urea nitrogen and a marked reduction in the plasma bromosulphthalein clearance.  相似文献   
222.
A new micro-method was used to evaluate in vitro sensitivity of ovine peripheral blood lymphocytes (PBL) to different non specific mitogens (pHA, Con A, PWM) and to investigate the interest of a colorimetric assay for measurement of transformed lymphocytes.

The results showed that sheep PBL in flat-bottomed microplates responded optimally at a cell density of 8 × 106 cells/ml to PHA (2.5 μg/ml), Con A (5 μg/ml) and PWM (5 μg/ml).

The colorimetric assay using a tetrazolium salt (MTT), for measuring the transformed lymphocytes, is very well correlated with the classical method of [3H]thymidine incorporation.

This new revelation technique of the mitogenic response improve the technical value of the assay, which is more rapid and easy-to-read, without diminishing the biological value.  相似文献   

223.
Strangles is an acute disease of horses caused by infec- tion with Streptococcus equi. It is characterized by inflamma- tion of the upper respiratory tract and abscessation in the adjacent lymph nodes. The distribution of strangles is world- wide. When an outbreak does occur in a large group of horses, it is usually restricted to the younger age groups, under adverse climatic conditions, and when shelter is inadequate. When the group is made up of predominantly young horses, up to 100% may be affected. Such a high incidence is encountered soon after large numbers of susceptible horses, which may have come from many localities, are stabled to get her. The source of infection is the nasal discharge from infected animals, which contaminates the pasture and feed and water troughs. Infection occurs by ingestion or by inhalation o f droplets. During April (1990), two cases of strangles were diag- nosed at Veterinary Faculty Teaching Hospital in Tehran. An epizootiological survey commenced immediately and showed 89-100% of horses were affected. The clinical symp- toms were severe in young horses and the mortality rate was zero. All of the infected horses responded to treatment with intramuscular injection of penicillin/streptomycin.  相似文献   
224.
The results of two stocking density trials on the nursery and grow-out stages of Epinephelus tauvina (Family: Serranidae), in PVC-lined raceways are presented.
At the nursery stage, fry of 17.1 g initial mean weight showed no significant differences in growth rate, survival rate and condition factor when stocked at densities of 200 and 400 fish/m3 over a period of 52 days. Fish grew to mean weights of 61.7 and 63.7 g, giving growth rates of 0.86 and 0.90 g/fish/day and final biomasses of 12.1 and 2S.2 kg/m3 for densities of 200 and 400 fish/m3, respectively. Survival rates were excellent for both treatments at 98percnt; or greater. Food conversion efficiency was slightly improved at the higher density.
At the grow-out stage, E. tauvina of mean weights ranging from 150-170 g cultured for a period of 215 days grew better at a density of 5 fish/m3 than at densities of 20 and 60 fish/m3 (final size: 770, 560 and 450 g with growth rates of 2.8, 1.8 and 1.4 g/fish/day, respectively). Survival rates were higher at the two lower densities. Overall, total biomass increased with stocking density (3.9, 11.1 and 23.4 kg/m3, for 5, 20 and 60 fish/m3, respectively). These results indicate that hamoor has potential to be successfully cultured in raceways.  相似文献   
225.
This study was conducted to evaluate the effect of supplying two levels of Acacia nilotica (A. nilotica) pods to rations of sheep on nutrient digestibility, nitrogen balance and rumen liquor parameters (pH, total protozoa count, protein concentration and enzymes activity). Twelve mature rams (50 ± 1.25 kg B.W.) were distributed into three groups, each with four rams. Animals in group one were considered as a control which fed a basal diet, consisting of concentrate mixture and Egyptian clover. The second group and the third one received the same basal diet with supplying the concentrate mixture by 1.5% and 3.0% of A. nilotica pods meal respectively. The experiment lasted for 3 weeks. It was found that supplementation of A. nilotica pods to the concentrate mixture at a rate of 1.5% and 3.0% significantly improved the total feed intake compared to the control. The digestibility of dry matter and crude fibre was significantly reduced with A. nilotica supplements, whereas the digestibility of crude protein was significantly improved. All of nitrogen intake and N‐retained were significantly increased in rams fed on concentrates with 1.5% and 3.0% A.  nilotica pods when compared to the control. The pH of ruminal fluid was not affected by the dietary treatments. Nevertheless, the total rumen protozoa count was significantly decreased in A. nilotica pods supplemented groups. Also, the rumen protein concentration and the ruminal enzymes activity, especially α‐amylase, cellulase and protease, were lower in A. nilotica pods supplemented treatments. In conclusions, inclusion of low levels of A. nilotica pods (1.5% and 3.0%) in the concentrates can be used as a natural protein protectant in ruminants by forming tannin protein complexes in the rumen to maximize the amino acids available in the lower digestive tract. Also, these levels can increase the protein digestibility as well as the N‐retained in the body .  相似文献   
226.
This study was conducted in 2007–2008 to determine the effects of different irrigation regimes on yield, quality and water-yield relationships of young dwarf ‘Gala, Galaxy’ apple trees in Isparta-Turkey. Irrigation water was applied based on a ratio of class A pan evaporation (rates of 0.0 (kcp0), 0.25 (kcp1), 0.50 (kcp2), 0.75 c (kcp3), 1.00 (kcp4) and 1.25 (kcp5)) with 5-day intervals. The effects of irrigation regimes on yield and fruit weight were statistically significant. Seasonal evapotranspiration was measured as 246.5–608.2 mm and 289.3–631.9 mm in 2007 and 2008, respectively. Water use efficiency lead to a yield ranging from 0.0023 to 0.0055 t ha?1mm?1 and from 0.0033 to 0.0111 t ha?1mm?1 and irrigation water use efficiency varies from 0.0009 to 0.0073 t ha?1mm?1 and from 0.0045 to 0.0186 t ha?1mm?1 in 2007 and 2008, respectively. The annual average yield response factor, ky, was 1.22. As a result of the research, it was concluded that the irrigation schedule for the 0.75 kcp3 treatment, applying 0.75 of evaporation from class A pan, could be used in the irrigation of young dwarf apple trees without evident reduction in yield and that high water use efficiencies could be obtained.  相似文献   
227.
Women in Turkey were first given the opportunity to attend schools of higher education in 1914. Following the establishment of the Turkish Republic in 1923, a number of social, judicial, and economic reforms took place that enabled women to participate actively in both the public and private sectors, and, as a consequence, the number of women students in higher education increased rapidly. The first woman graduated from the veterinary school in Ankara in 1935, becoming the first female veterinarian in the country. Since that time, the number of female veterinary graduates in Turkey has steadily increased.  相似文献   
228.
In this study, the body measurements (BMs) of Holstein cows were determined using digital image analysis (IA) and these were used to estimate the live weight (LW) of each cow. For this purpose, an image capture arrangement was established in a dairy cattle farm. BMs including wither height (WH), hip height (HH), body length (BL), hip width (HW), plus the LWs of cows were first determined manually, by direct measurement. Then the digital photos of cows were taken from different directions synchronously and analyzed by IA software to calculate WH, HH, BL and HW of each cow. After comparing the BMs obtained by IA with the manual measurements, the accuracy was determined as 97.72% for WH, 98.00% for HH, 97.89% for BL and 95.25% for HW. The LW estimation using BMs was then performed by the aid of the regression equations, and the correlation coefficient between the estimated and real (manual) LW values obtained by weighing was calculated as 0.9787, which indicates the IA method is appropriate for LW estimation of Holstein cows.  相似文献   
229.
We modeled the flowering and capsule set dynamics, quantified the level of variation in seed characteristics, elucidated the inter-relationships between seed and capsule physical dimensions, and quantified their impact on single seed weight in the cuphea germplasm line PSR23. Temporal patterns of flowering and capsule set were largely time-dependent and highly auto-correlated, with significant autoregressive parameters of number of flowers (0.76) and number of capsules (0.74). Large numbers of seeds per capsule were associated with large coefficient of variation in single seed weight. Seed number and seed weight per capsule, when log-transformed, exhibited a slope of −0.65 indicating that cuphea plants have only a limited capacity to maintain seed weight by adjusting seed number if resources vary. Capsule tissue/seed weight ratio and number of seeds per capsule have the largest potential impact on single seed weight. Sensitivity analyses indicated that capsule perimeter (>76 mm), capsule major (>23 mm) and minor axes (>7.0 mm), capsule circularity (between 0.350 and 0.375), capsule area (<85 mm2), capsule tissue/seed weight ratio (<0.40), and number of seeds per capsule (∼9.0) would optimize single seed weight. This information would help plant breeders exploit genotypic variability in seed and capsule characteristics and agronomists identify optimum trait combinations to produce high yields of this potential oilseed crop.  相似文献   
230.
On-farm measurements and observations of water flow, water costs and irrigation labour inputs at the individual parcel level were made in case studies of smallholder irrigation systems in sub-Saharan Africa and south-eastern Arabia. The systems, in which the water source supplied either single or multiple users, were analysed to address the fundamental issues of labour allocation for on-farm water management as this has important consequences for the success of such systems. Results show that the costs associated with accessing water influenced labour input, because when they were low the farmers tended to increase the irrigation rate and reduce the amount of time they spent distributing the water within their parcels. Conversely when water costs were high, lower flow rates and more time spent in water distribution were observed, and this resulted in more uniform irrigation and higher irrigation efficiency. Also, opportunities and demands for farmers to use their labour for activities other than irrigation can lead them to modify operational or physical aspects of the system so that they can reduce the time they spend distributing water within the parcels, particularly when the water is relatively cheap. Awareness and better understanding of how farmers may allocate their labour for water management will lead to more effective planning, design and management of smallholder irrigation systems.  相似文献   
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