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31.
Phytoparasitica - Moths of Coniesta ignefusalis (Hampson) were collected by automatic light traps on millet field near Bamako in 2018. The light trap data shows three periods of moth flight. The...  相似文献   
32.
AIMS: To retrospectively evaluate the medical and surgical records of horses with acute small intestinal obstructions associated with Parascaris equorum infection; to describe the gastrointestinal lesions; and to determine the outcome of cases with such lesions.

METHODS: Records of 25 horses with acute small intestinal obstruction associated with P. equorum between 1985 and 2004 were reviewed to determine signalment, history, physical examination, surgical or post-mortem findings, and outcome.

RESULTS: All horses except one were less than 12 months old. Standardbreds were over-represented in the population studied. Sixteen horses (72%) had been administered anthelmintics, including pyrantel (n=8), ivermectin (n=7), and trichlorphon (n=1), within 24 h prior to the onset of colic. Of the 25 cases reviewed, 16 had simple obstructive ascarid impactions (SOAIs), and nine had complicated obstructive ascarid impaction (COAI) including volvulus (n=6) or intussusception (n=3), both concurrent with ascarid impaction of the small intestine. Short-term survival (discharge from hospital) occurred in 79% of horses treated for SOAI, and was 64% for all horses. Long-term survival (>1 year) occurred in 33% of horses with SOAI, and the overall long-term survival was 27% for all horses. Formation of adhesions was the most frequent finding associated with death for horses that did not survive long-term.

CONCLUSIONS AND CLINICAL RELEVANCE: The incidence of anthelmintic treatment within 24 h of the onset of colic in this study population (72%) was higher than that previously reported. Resistance of P. equorum to ivermectin recently reported in Ontario may be associated with increased ascarid burdens, predisposing horses to ascarid impaction. The long-term survival of these horses was better than that reported previously.  相似文献   
33.
Gene flow between cultivated and their wild relatives is one of the main ecological concerns associated with the introduction genetically modified (GM) cultivars. GM sorghum cultivar has been developed and its commercial production may be possible in the near future. The rate of gene flow depends on the fitness of wild × cultivated sorghum hybrids. The study aimed at estimating adaptive values of wild × cultivated sorghum hybrids in generations F1, F2, and F3 compared to their parents. Artificial crosses of four wild sorghums, five cultivated sorghums, and two male sterile lines were made to produce the F1 generation, which were advanced to F2 and F3. Each hybrid generation and their respective parents were evaluated for their adaptive value at two sites in a randomised complete block design with seven replicates. The resulting progenies did not show serious fitness penalties. Some hybrids were as fit as their respective wild parents and no consistent differences exist between the three generations studied. Thus, the resultant wild × cultivated hybrids may act as avenue for introgression.  相似文献   
34.
The range and infestation intensities of gastrointestinal parasitic nematode species depend on the type of swine production system. The present study focused mainly on nematodes of veterinary importance in scavenging pigs in Burkina Faso, and aimed at determining the prevalence of gastro-intestinal nematode parasites by means of faecal egg per gram (EPG) counts. Between November 2001 and October 2002, faecal samples from 383 pigs of different sexes and ages (< 5 months, 5-12 months and > 12 months) were collected from the rectum and examined for gastrointestinal nematodes parasites using the Mc Master method. Of the 383 pigs examined, 91% were infected by one or more parasites. Ascaris suum (40%; 100-1 400 EPG) was the most prevalent parasite followed by Strongyloides ransomi (21%; 100-4200 EPG), Oesophagostomum spp. (18%; 100-1000 EPG), Hyostrongylus rubidus (11%; 100-1 800 EPG), Globocephalus spp. (10%; 100-400 EPG) and Trichuris suis (1 %; 100-200 EPG). The prevalence was significantly higher in female pigs (n = 239) than in males. In addition, females excreted significantly (P < 0.05) more eggs in their faeces than males, except in the case of Globocephalus spp. The age of the animal had no effect on the prevalence of A. suum whereas there were significant differences in age categories concerning S. ransomi, H. rubidus, Oesophagostumum spp. and Globocephalus spp. Unexpectedly, the high prevalence of these common parasites was not accompanied by elevated EPG values, which suggests the existence of moderate infestations. The present work indicates that the common nematode infestations in pigs do not necessarily need a systematic herd anthelmintic treatment, as only a small number of worms is required to induce immunity. A further study is needed to formulate appropriate and cost-effective strategies for the control of gastro-intestinal nematode parasites in pigs in Burkina Faso.  相似文献   
35.
广州地区禽类隐孢子虫病的初步调查   总被引:7,自引:0,他引:7  
采用饱和蔗糖浮卵法,对广州地区5个鸡场,5个鸭场和3个鹅场的隐孢子虫自然感染情况进行了调查,882份鸡的粪样中隐孢子虫卵囊阳性者有124份,其阳性率为74.1%,1004份鸭的粪样中阳性者273份,其阳性率为27.2%,571份鹅的粪样中阳性者为71份,其阳性率为12.4%,根据卵囊形态和大小,卵囊鉴定为贝氏隐孢子虫。  相似文献   
36.
Leptin acts on energy metabolism, affecting reproductive functions through activation of its receptors in the brain and in reproductive organs. This study compared the presence of leptin and its receptor (ObR‐b) in hypothalamus neurons, endometrial glands and oocytes of culled swine females across ovarian statuses and parities. Immunohistochemistry was done in samples of uterus, ovaries and hypothalamus from 28 culled females, using polyclonal antibodies antileptin and ObR‐b. Immunolabelling was compared for sows categorized by parity at culling (0, 1, 2–4 and <4) and ovarian status (luteal and follicular phases of the oestrous cycle and with cysts). Immunolabelling for leptin and ObR‐b in neurons and oocytes was weaker in females with cysts (p < 0.05) than in those at the follicular phase. In endometrial glands, leptin immunolabelling was less intense in females with cysts (p < 0.05), but immunolabelling for ObR‐b was similar across ovarian statuses (p > 0.05). In sows culled with 2–4 parities, leptin immunolabelling in neurons and endometrial glands was more intense than in nulliparous females (p < 0.05). In comparison with sows culled at greater parities, ObR‐b immunolabelling for nulliparous females was less intense in endometrial glands and in oocytes (p < 0.05), but more intense in neurons (p < 0.05). Thus, in swine, the presence of leptin and ObR‐b varies across parities and is more intense in the uterus, ovaries and hypothalamus of females that were cycling before culling than in those having cystic ovaries.  相似文献   
37.
Cereal production is chronically deficit in the Timbuktu region of Mali, sufficient for only 4.5 months of annual household consumption. Small-scale, village-based irrigation schemes, usually 30–35 ha in size, irrigated by a diesel motor pump, have become important to improve food security in this arid region. The NGO Africare has worked during the past 12 years with farmers in Goundam and Dire circles to establish irrigation schemes and provide them with technical assistance. In 2007, Africare undertook a first test of the System of Rice Intensification (SRI) in Goundam circle. After farmers observed a yield of 9 t ha−1 of paddy compared to 6.7 t ha−1 in the control plot there was interest in larger scale testing of the SRI system. In 2008, Africare, in collaboration with the local Government Agriculture Service and with support from the Better U Foundation, implemented a community-based evaluation of SRI with 60 farmers in 12 villages. Farmers in each village selected five volunteers, who each installed both SRI and control plots, side by side, starting the nurseries on the same day and using the same seed. For SRI plots, seedlings were transplanted one plant hill−1 at the two-leaf stage (on average, 11.6 days old), with spacing of 25 cm × 25 cm between hills and aligned in both directions. This allowed farmers to cross-weed with a cono-weeder, on average 2.4 times during the season. In the control plots, farmers planted 3 plants hill−1 with seedlings 29.4 days old and spaced on average 23.7 cm, not planted in lines. Weeding was done by hand. 13 t ha−1 of organic matter was applied under SRI management, and 3 t ha−1 in the control plots. Fertilizer use was reduced by 30% with SRI compared to the control. Although alternate wetting and drying irrigation is recommended for SRI, this was not optimally implemented due to constraints on irrigation management within the scheme; thus water savings were only 10% compared to the control. Average SRI yield for all farmers reached 9.1 t ha−1, with the lowest being 5.4 t ha−1 and highest being 12.4 t ha−1. SRI yields were on average 66% higher than the control plots at 5.5 t ha−1, and 87% higher than the yields in surrounding rice fields at 4.9 t ha−1. Number of tillers and panicles hill−1, number of tillers and panicles m−2, and panicle length and number of grains panicle−1 were clearly superior with SRI compared to control plants. Farmers tested five varieties, all of which produced better under SRI. The SRI system allowed for a seed reduction of 85–90%: from 40–60 kg ha−1 for the control plots to 6.1 kg ha−1 under SRI. Although production costs per hectare were 15% higher for SRI, revenue was 2.1 times higher than under the control. Farmers were very satisfied with these results. In 2009/2010, Africare and the Government’s agriculture service worked with over 270 farmers in 28 villages to scale up SRI practices and to test innovations, including composting techniques, optimization of irrigation, and techniques to reduce labor requirements and production costs. The good crop performance along with other advantages was confirmed in this third year with SRI yields of 7.7 t ha−1 (n = 130 farmers) compared to 4.5 t ha−1 in farmers’ fields.  相似文献   
38.
The terminal navigation of the Near Earth Asteroid Rendezvous (NEAR) spacecraft during its close flyby of asteroid 253 Mathilde involved coordinated efforts to determine the heliocentric orbits of the spacecraft and Mathilde and then to determine the relative trajectory of the spacecraft with respect to Mathilde. The gravitational perturbation of Mathilde on the passing spacecraft was apparent in the spacecraft tracking data. As a result of the accurate targeting achieved, these data could be used to determine Mathilde's mass as 1.033 (+/- 0.044) x 10(20) grams. Coupled with a volume estimate provided by the NEAR imaging team, this mass suggests a low bulk density for Mathilde of 1.3 grams per cubic centimeter.  相似文献   
39.
Seasonal behaviour in sheep, which varies in tropical and temperate environmental conditions, is a matter of study, because it can provide a clue to address the problem of seasonality in sheep. Melatonin receptor is the membrane‐bound G‐coupled receptor, sensing the message of photoperiodic cues thorough melatonin. Restriction fragment length polymorphism (RFLP) studies were carried out to assess the variability of gene at G612A and C606T SNPs in MTNR1A gene, which have been studied to be markers for out‐of‐season breeding. Allelic frequency distribution corresponded to higher frequency of GG and CC genotype, in tropical arid sheep breed in comparison with temperate region sheep breed. PCR amplification of MTNR1A gene of 30 animals was performed and single nucleotide polymorphisms (SNPs) identification was carried out using Lasergene software. Seven SNPs/mutations were identified, but most of them were synonymous, except the one G706A, leading to substitution of valine by isoleucine. Polyphen‐2 analysis of G706A mutation revealed that it is a benign mutation. Two important SNPs C426T and G555A, which were identified in temperate sheep breeds, could not be traced in Magra and Marwari breeds of sheep. Thus, the Magra and Marwari breeds of tropical, arid region demonstrated the presence of both polymorphic SNPs markers G612A and C606T, associated with out‐of‐season breeding. GG and CC genotypes were having a higher prevalence in the studied population.  相似文献   
40.
Nontimber forest products are a source of income for women in rural African communities. However, these products are frequently damaged by insect pests. The present study investigates the diversity and damage rates of insect pests that attack Carapa procera seeds and Lophira lanceolata fruits. The experiment was set up in western Burkina Faso and, for C. carapa, consisted of pests collected from seeds that had fallen to the ground and from stockpiled seeds. For L. lanceolata, pests were collected from fruits on the trees, and on the ground. The collected samples were sent to the laboratory to estimate the proportion of damaged seeds/fruits and rear the insects. The results showed that Ephestia spp., Tribolium castaneum, Oryzeaphilus spp., and Tenebroides mauritanicus were the pests of Carapa procera seeds and Lophira lanceolata fruits. Ephestia spp. was recorded as the main pest of both C. procera and L. lanceolata, whereas T. castaneum was only detected from seeds of L. lanceolata. For C. procera, the stocks were the most infested (29 %) by Ephestia spp. The infestation rate of fruits of L. lanceolata by Ephestia spp. on trees (31.42 ± 3.75 %) was less than the rate of fruits by T. castaneum on the ground (44.00 ± 3.5 %). The different body sizes of Ephestia spp. may indicate the occurrence of two putative species, one from C. procera and another one from L. lanceolata. This work provides important information that could contribute to the setting up of a local-scale sustainable management framework for oil tree pests in Burkina Faso and surrounding countries.  相似文献   
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