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81.
Shamsuddin M Goodger WJ Hossein MS Azizunnesa Bennett T Nordlund K 《Tropical animal health and production》2006,38(2):131-140
Identified economic opportunities for planning interventions greatly increase farmers’ compliance with an extension programme.
We investigated opportunities for interventions to increase dairy farmers’ income in four areas of Bangladesh, including the
districts of Mymensingh, Khulna-Satkhira, Sirajgonj-Pabna and Chittagong. The data were collected from 1440 dairy farms at
a one-day visit and were summarized as the difference between management targets and each herd’s calculated management indices.
The average number of lactating cows, feed cost as a percentage of income from milk, milk sold as percentage of milk produced,
lactating cows as a percentage of mature cows, and lactating cows as a percentage of total cattle varied from 1.5 to 3.4,
from 52.5% to 92.1%, from 78.7% to 92.6%, from 81.9% to 86.7% and from 34.3% to 37.7%, respectively. The average age at first
calving, calf production interval, lactation length, and milk production were 35.0–44.3 months, 14.0–17.6 months, 249–286
days and 3.5–7.2 litres, respectively, depending on the locality. The average cost for producing 100 litres of milk was 18.9–35.1
US dollars. The production cost increased when daily milk production per cow decreased (r2 = 0.43–0.55). Management improvements directed towards increasing average milk production per cow per day, increasing lactation
length, decreasing age to first calving, and decreasing calf production interval could expect to yield an average income increase
up to a range of 676.3–1730.6 US dollars depending on the milk-producing area. 相似文献
82.
Bentley AM Goldschmidt MH Bennett RA 《Journal of the American Animal Hospital Association》2006,42(3):223-225
A 5-year-old, neutered male, mixed-breed dog was evaluated for a fluctuant mass in the right midcervical region. The mass recurred following aspiration of its contents and after removal of the right sublingual and mandibular salivary glands. The lateral midcervical location of the mass and the serous nature of the fluid within the mass were inconsistent with a salivary mucocele. Excisional biopsy was curative and revealed an intestinal choristoma. 相似文献
83.
84.
Tiffani J. Howell Samia Toukhsati Russell Conduit Pauleen Bennett 《Journal of Veterinary Behavior: Clinical Applications and Research》2013,8(6):425-430
Dog (Canis familiaris) cognition research that examines whether dogs are able to use a mirror as a problem-solving tool is rare. The aim of this study was to explore whether dogs could find food that was visible only via a mirror at the beginning of the experiment. In a laboratory setting, we exposed 44 dogs to a large mirror, attached at a 90° angle to an opaque barrier for 10 minutes. Dogs were allowed complete freedom of movement. For the first minute of the exposure phase, the owner and experimenter stood against a wall, ignoring the dog; afterward, both walked around the room for 9 minutes. The dogs could observe their movements in the mirror. Then, dogs were taught to associate a bowl with food, after which the bowl was surreptitiously placed behind the barrier, and the dogs were positioned so that they could see the reflection of the food in the mirror. Dogs were pseudorandomly assigned to the experimental group (n = 22) as described or a control group (n = 22), which was identical except that the mirror was covered during the testing phase. In the testing phase, dogs that could see the mirror were more likely to find the treat than dogs that could not (P = 0.032). Although fewer dogs in the control condition found the food, those that did were just as likely as those in the mirror condition to locate it within 3 minutes. This suggests that, although dogs' food-searching behavior can be triggered by the mirror's visual cues to locate food, some dogs used other cues that we were unable to control. 相似文献
85.
86.
Intertidal fish communities in the south·western Cape have a high density and biomass, implying that the fish are important con· sumers in the ntertidal zone. Stomach content analyses of 20 species were undertaken to ascertain which food resources are most heavily exploited and the extent to which the co-existing fish compete for the same food resources. Three prey types, arnphipods, isopods and polychaetes, occur in the diets of almost all the species examined and together comprise more than half the total volume consumed by 14 of the species. Despite the overlap in food types consumed, there was considerable subdivi· sion of the resource, much of which may be explained in terms of horizontal and vertical distribution patterns of the various fish species, their habitat preferences, mouth sizes and changes in diet during growth. The standing stock of food in the pools is thought to be too low to support the resident fish populations, suggesting that some food, at least, is obtained outside the pools while the tide is in. For this reason, the fish are considered to be concentrated in the pools at low tide, indicating that the availability of suitable pool habitats may be important in con· trolling the denSities of intertidal fish communities. 相似文献
87.
Extract Sir:- In June 1982, possums (Trichosurus vulpecula) from the Waitahuna forest area near Lawrence in Central Otago were examined for endoparasites (181 possums) and ectoparasites (125 possums). The alimentary tract was separated into stomach, small intestine and large intestine. These sections were washed thoroughly through a 60 mesh sieve and total parasite counts and identification were carried out. The fur from the base of the forelegs along the back and around the base of the tail was digested in 20% KOH and the ectoparasites were recovered. There was no evidence of pathogenicity ascribable to the parasites found. A summary of results is presented in Table I. 相似文献
88.
89.
水稻β-淀粉酶基因密码子使用特性分析 总被引:1,自引:0,他引:1
本研究分析了水稻10个β-淀粉酶基因(OsBmy1~OsBmy10)在cDNA和蛋白质上的同源性,分析了每个基因反映密码子使用特性的参数——GC含量、同义密码子第1~3位置中的GC含量、有效密码子数和相对同义密码子使用度。结果表明:水稻β-淀粉酶家族基因序列间的同源性差异较大,在cDNA和蛋白质序列上的基因同源性分别为39.2~79.6和25.9~74.0,其中,OsBmy3和OsBmy9间的同源性最高;OsBmy3、OsBmy4、OsBmy5、OsBmy7、OsBmy9和OsBmy10等为高GC含量基因,并表现出极强的密码子使用偏好。可见,水稻β-淀粉酶基因在进化过程中不仅氨基酸组成发生了分化,而且其在氨基酸密码子使用偏好上也发生了分化。 相似文献
90.
Folate Polyglutamylation is Required for Rice Seed Development 总被引:1,自引:0,他引:1