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试验设计用清水作对照,用有效氯含量分别为0．3％、0．5％、0．7％的漂白粉消毒液进行桑叶叶面消毒,用消毒过的桑叶饲育原原种(7532),调查各饲育区的饲育成绩、茧质成绩和卵质成绩等各项指标,探讨不同浓度的消毒液消毒叶面对蚕种繁育成绩的影响。结果为:用含有效氯0．3％和0．5％的漂白粉消毒液处理桑叶,饲育区的幼虫生命率、死笼率、全茧量、茧层量、总卵数、良卵数与对照区相比均无显著差异;含有效氯0．7％的消毒液处理桑叶,除茧质没有影响之外,饲育区的幼虫生命率降低、死笼率增加、总卵数、良卵数降低,与对照区相比较达到极显著差异。试验结果显示,利用漂白粉进行桑叶面消毒时,消毒液有效氯浓度应控制在0．3％～0．5％之间,既不影响蚕种繁育的产量和质量,又可以有效地预防微粒子病的发生。 相似文献
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目前广西家蚕一代杂交种有95％以上是在农村原蚕区生产,原蚕区的养蚕环境的好坏对蚕种生产有直接的影响。蚕种生产单位一般只注重养蚕环境的消毒,而忽视桑园环境的消青。多年的实践证明桑园环境被污染是引起家蚕微粒子病发生的重要原因之一,本文把蚕种生产中通过加强桑园环境消毒,提高防“微”效果的一些措施加以总结,供大家参考。 相似文献
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蚕种是蚕茧生产、丝绸生产的基础，蚕种是一种特殊的鲜活生物种子，蚕种生产各环节的特殊性决定了蚕种生产的计划性和管理的重要性。因此，在蚕种生产过程，提高蚕种质量，显得十分重要。近年来在蚕种生产过程中，不良卵特别是不受精卵的发生量有所增加，使得良卵数减少影响了蚕种产质量。为此，尽量减少不受精卵， 相似文献
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桑叶叶面消毒是预防家蚕微粒子病的一项重要技术措施，已在蚕种生产中广泛应用。科学有效地做好叶面消毒工作，对降低微粒子病的发生，减少蚕种淘汰率，提高蚕种质量和种场经济效益意义重大。 相似文献
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提高蚕种杂交率的措施湖州市蚕桑站吴怀民湖州市蚕研所冯建琴近年来，少数蚕种生产单位在追求经济效益的同时忽视了蚕种质量，造成了不良影响。当前最突出的问题之一是蚕种杂交率下降，不同程度上影响到蚕茧产质量和蚕农的收益。要解决这个问题，不能单靠某一个环节，而应... 相似文献
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桑蚕卵电晕人工孵化技术研究：V.电晕处理蚕种的农村饲育 总被引：2，自引：0，他引：2
通过１９９４～１９９６年电晕处理蚕种的农村饲养，得到以下几点认识，在保证卵面消毒和排除孵化不齐因素情况下，电晕蚕种与浸酸蚕种的产量质量无显著差异，专供农用的大板电晕仪存在放电不匀，孵经不齐和孵化率欠高的问题，有待改进，电晕处理蚕种还须进行卵消毒。 相似文献
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桑园管理工作与蚕种生产存在着相互制约、相互促进的内在联系，它直接关系到桑树的生长势，桑叶的产量，叶质的优劣，影响蚕种的产量和质量。抓好桑园管理是蚕种生产稳产、高产、优质的重要基础。近年来，各蚕种生产单位已充分认识到桑园管理水平的提高，对提高蚕种产质量的重要性，并把它列为种场综合管理的主要内容。 相似文献
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K Ostlund 《Acta veterinaria Scandinavica》1971,12(4):479-488
The ability of the eggshell to resist penetration of Salmonella bacteria was studied in unwashed and in hand washed eggs, and in eggs, which had been subjected to industrial, large-scale machine washing under strictly controlled conditions.In one part of the investigation, concerning unwashed and machine washed eggs, a defined amount of a broth culture of Salmonella typhi murium was applied on the shell surface, whereafter the eggs were incubated at 4°C for eight weeks or at 30°C for 12 days. At the end of the storage period, the egg contents were examined for the presence of Salmonella. No Salmonella bacteria were detected in the 120 eggs investigated.In another part of the investigation, dealing with 200 unwashed, 200 hand washed and 200 machine washed eggs, a broth culture of Salmonella was applied on the shell surface of eggs, whose contents had been poured out through an opening. In every second egg of each kind, the shell membranes had been scraped off over an area, corresponding to the placement of the bacterial inoculum. The eggshells were filled with enrichment broth and the occurrence of Salmonella bacteria in this broth was examined after incubation.In the eggs with intact shell membranes, the frequencies of Salmonella positive enrichment broths were for unwashed eggs 0.12, for machine washed eggs 0.10, and for hand washed eggs 0.22. The corresponding frequencies in eggs with removed shell membranes were 0.27 (unwashed), 0.42 (machine washed), and 0.60 (hand washed).No statistical difference occurred between unwashed and machine washed eggs when the shell membranes were intact. When the shell membranes were removed this difference was statistically almost significant. The difference between machine washed and hand washed eggs with intact shell membranes was statistically almost significant, while the same difference was highly significant in eggs with removed shell membranes.The author assumes, from the results of the present and a preceding investigation, that the applied washing procedure in no way harms any essential storage properties of uncracked eggs. Considering the known occurrence of hand washing of eggs in Swedish farms — a treatment with documentedly unfavourable influence — it would be desirable if all eggs could be subjected to machine washing under strictly controlled conditions at the grading stations. Such an arrangement ought to result in an increase in the average bacteriologic-hygienic quality of eggs for market. 相似文献
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Effects of source and washing of RBC on quantitative growth and hemolytic zone sizes of common bacterial pathogens of the bovine mammary gland were evaluated. Blood samples used to prepare the blood agar media were obtained from 10 adult dairy cows, 10 dairy calves, and 10 sheep. Hemolytic zone sizes produced by Staphylococcus aureus were significantly (P less than 0.01) larger on blood agar prepared with washed RBC than on blood agar prepared with nonwashed RBC, regardless of RBC source. With the exception of Corynebacterium bovis, growth of all bacteria was equivalent or significantly higher on medium prepared with washed RBC, compared with that on medium prepared with nonwashed RBC, regardless of RBC source. Significantly higher numbers of C bovis (P less than 0.01) and Streptococcus agalactiae (P less than 0.01) were isolated on medium prepared with washed cow RBC. Significantly higher numbers of Str uberis (P less than 0.01) and S aureus (P less than 0.05) were isolated on medium prepared with washed sheep RBC and washed calf RBC, respectively. Growth of Escherichia coli was not affected by the RBC source. Seemingly, RBC used in the preparation of medium should be washed. The source of RBC, as well as inter-animal variation, also should be considered in the quality control of medium. 相似文献
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F Cabrera F González M Batista P Calero A Medrano A Gracia 《Reproduction in domestic animals》2005,40(3):191-195
Goat semen is different from that of other domestic species in its limited tolerance to the inclusion of egg yolk in the freezing medium, and this tolerance depends on the presence of enzymes in the seminal plasma that react with egg yolk, producing toxic compounds to the spermatozoa. Moreover, the goat is a seasonal breeder that shows variations in semen quality throughout the year, and those variations may affect semen freezability; hence in freezing protocols, for instance, removal of seminal plasma (washing) yields varying results. This work was designed to study this problem in Canary goats: semen from six males was collected in spring, autumn or winter, washed or non-washed, diluted in a freezing extender with 1.5, 6 or 12% egg yolk, frozen, and thawed after 2 days, 2 or 6 months of cryopreservation. The effect of egg yolk concentration in the freezing extender was far more important than the effect of washing or season on sperm cryosurvival. The quality of frozen-thawed semen tended to improve as egg yolk concentration increased regardless of the effects of season, washing or period of cryopreservation. Washing produced a positive effect on frozen-thawed semen collected during spring or autumn, but the difference decreased as the concentration of yolk increased. However, washing produced a negative effect on frozen-thawed semen collected during winter, diluted with either 6 or 12% egg yolk. There was no apparent seasonal effect on gross measures of sperm production but the seasonal effect was ever present and was reinforced by freezing. 相似文献
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Bacterial Populations of Broiler Carcasses Washed in Mixtures of Potassium Hydroxide and Lauric Acid
《The Journal of Applied Poultry Research》2007,16(3):387-391
The bactericidal effect of mixtures of KOH and lauric acid (LA) on the microflora of broiler carcasses was examined. Carcasses were washed by shaking in KOH-LA for 1 min on a mechanical shaker. In one set of experiments, the population of bacteria recovered from carcasses following each of 3 successive washes in 1.0% KOH-2.0% LA or in distilled water (control) was enumerated. The number of total plate count bacteria, Campylobacter, and Escherichia coli in aliquots of whole-carcass-rinses of the washed carcasses was determined. Results indicated that fewer bacteria were generally recovered from carcasses after each successive wash in KOH-LA or distilled water, but significantly fewer bacteria were recovered from carcasses washed in KOH-LA than from carcasses washed in distilled water. Bacteria recovered from carcasses after the first and third wash in KOH-LA were identified using the MIDI Sherlock Microbial Identification System. Gram-positive and gram-negative bacteria were identified in the bacterial flora of carcasses washed once in KOH-LA; however, only gram-positive cocci were identified in the bacterial flora of carcasses washed 3 times in KOH-LA. Additional experiments were performed to compare the number of bacteria recovered from carcasses washed 2 times in 0.25% KOH-0.5% LA, 0.5% KOH-1.0% LA, or 1.0% KOH-2.0% LA or in distilled water (control). Results indicated that significantly fewer bacteria were recovered from carcasses washed in higher concentrations of KOH-LA than from carcasses washed in lower concentrations of KOH-LA. Findings from these experiments show that washing carcasses in KOH-LA can reduce carcass contamination by bacteria responsible for human foodborne diseases and spoilage of fresh poultry. 相似文献
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K Ostlund 《Acta veterinaria Scandinavica》1971,12(4):467-478
The influence of egg washing on the bacterial counts of egg contents after subsequent storage was studied. Unwashed eggs were compared to eggs subjected to industrial large-scale machine washing. The washing procedure consisted of sprinkling under pressure with a 43 °G water solution of detergent, rinsing with 47°G tap water, and drying in a stream of hot air (60–65°G). The eggs were stored at 4°C for eight weeks and at 30 °G for 12 days. At the end of the storage periods, the total bacterial count, the number of hemolytic bacteria, and the number of coli-aerogenes in the egg contents were examined. A total of slightly more than 400 eggs were used in the investigation.No coli-aerogenes bacteria were detected in any washed or unwashed eggs. For eggs, stored at 4°C, the logarithmic total bacterial counts were for washed eggs 2.07; 2.42, and for washed 2.08; 1.95 (mean and median values, respectively). The corresponding values for eggs stored at 30 °G were for unwashed eggs 1.40; 1.30, and for washed eggs, 1.62; 1.48. These differences between unwashed and washed eggs are not significant.Hemolytic bacteria were detected in 35.2 % of unwashed and in 33.0 % of washed eggs after cold storage and no significant difference was seen between the number of bacteria in these eggs (logarithmic mean values 2.43 and 2.47, respectively). Nor was any significant difference seen between the counts of the hemolytic bacteria in eggs stored at 30 °G, where these bacteria were detected in 19.6 % of unwashed and in 23.9 % of washed eggs (logarithmic mean values of number of bacteria 2.10 and 2.46, respectively). The importance of obtained results is discussed from the point of view of food hygiene with references to the relevant literature. 相似文献
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Relation between respiratory activity and sperm parameters in boar spermatozoa cryopreserved with alpha‐tocopherol and selected by Sephadex 
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下载免费PDF全文 Our aim was to evaluate the effect of Sephadex filtration on respiratory activity of porcine spermatozoa and its relation with quality and functional sperm parameters. Samples were evaluated regarding oxygen uptake and sperm parameters: motility, plasma and acrosome membrane integrity, capacitation and acrosome reaction induction in vitro, plasma membrane functionality, determined by the hypo‐osmotic swelling test (HOST), and lipid peroxidation assessed by thiobarbituric acid assay. Sephadex filtration improved all routine quality parameters (motility, plasma and acrosome membrane integrity) and functional parameters (HOST, in vitro capacitation and true acrosome reaction levels) and produced a significant decrease in cryocapacitation and lipid peroxidation. Oxygen uptake increased in Sephadex samples (41 ± 7%) respect to single washing. Oxygen addition of carbonyl‐cyanide‐m‐chlorophenylhydrazone (CCCP) confirmed mitochondrial coupling in washed and Sephadex samples; showing an increase of 2.6 and 4.2 times for oxygen consumption in single washing and Sephadex ones, respectively. The increase in oxygen uptake with succinate addition with respect to basal oxygen uptake was significantly lower in Sephadex samples (63 ± 25%) than in the washed ones (183 ± 35%). Sephadex samples showed higher mitochondrial activity measured by oxygen consumption and improved quality and functional parameters. Our study recommends this protocol due to the fact that this filtration method removes dead or damaged spermatozoa allowing to obtain cryopreserved boar spermatozoa with optimized fertilizing capacity. 相似文献
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The standard washing and trypsin treatment procedures to remove viruses adhering to the zona pellucida (ZP) were evaluated. Mouse embryos at the early blastocyst stage were exposed to Sendai virus, and then washed or treated with trypsin. Even after washing or trypsin treatment, Sendai virus was detected in the twelfth and final wash. The virus was still shown to adhere to the ZP by immunofluorescence assay. The embryos developed into expanded blastocysts following 24 hours of in vitro culture. Viral antigen was clearly demonstrated in the cells forming the expanded blastocysts, indicating that viral replication occurred in these cells. The present results suggest that the standard washing or trypsin treatment are not sufficient to remove Sendai virus adhering to the ZP of mouse embryos. 相似文献
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Kalyan Sundar Das Ghansham Singh Shyam S. Paul Raman Malik Parminder S. Oberoi Sitanshu M. Deb 《Tropical animal health and production》2011,43(1):35-39
The effect of washing frequency on the physiological responses and performance of buffalo calves was studied in hot summer.
Thirty Nili-Ravi calves aged 4–6 months were divided into three uniform groups of ten. The calves of group A, B and C were
washed two (9 a.m. and 3 p.m.), three (8 a.m., 12 noon and 4 p.m.) and four (8 a.m., 11 a.m., 2 p.m. and 5 p.m.) times in
a day, respectively. They were washed with water for 5 min at a stretch. The mean linear body measurements, body weight, dry
matter intake through concentrate, green fodder and physiological responses, i.e. rectal temperature, pulse rate and respiration
rate before and after washing under different daily washing frequency were recorded fortnightly. The average daily gain was
also calculated. The mean total dry matter intake was increased with the increase frequency of washing. The maximum mean daily
body weight gain was recorded in group C followed by group B and A. There were statistically significant (P < 0.05) differences between the three washing groups. Calves were more comfortable with increase number of washing in a day
in hot summer. The rectal temperature, pulse rate and respiration rate also varied significantly (P < 0.05) between the three experiment groups. It can be concluded that daily four times washing in hot summer had more beneficial
effects over three and two times washing of young Nili-Ravi buffalo calves to decrease rectal temperature, pulse rate and
respiration rate and to increase average feed utilization and daily gain under tropical climate. 相似文献
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《The Journal of Applied Poultry Research》2006,15(3):457-463
A study was conducted to determine the effectiveness of an automated commercial washing system designed to clean chicken transportation cages. Surface swabs of flooring in chicken transport cages were collected before and after washing and again after sanitizer application and evaluated for recovery of bacteria. Cage wash water samples (CWW) were collected and assessed chemically and microbiologically. Washing cages significantly reduced levels of total aerobic bacteria, coliforms, and Escherichia coli recovered from flooring by 1.3, 1.6, and 1.5 log10 cfu/cm2, respectively. Levels of total aerobic bacteria, coliforms, and E. coli on flooring were further reduced by 0.7, 0.6, and 0.7 log10 cfu/cm2 after sanitizer application. Prevalence of Salmonella on unwashed flooring (1/27 positive), washed and sanitized flooring (0/27 positive), and in the CWW (1/9 positive) was low. Prevalence of Campylobacter (7/27 positive) on unwashed flooring decreased significantly when cages were washed and sanitized (2/27 positive). Counts of total aerobic bacteria, coliforms, and E. coli in CWW ranged from 2.0 to 4.0 log10 cfu/mL, and 1 of 9 CWW was positive for Campylobacter. Although the CWW collected from the second washing station appeared darker than the CWW collected from the first washing station, there was no statistical difference in total solids, total suspended solids, total dissolved solids, and chemical oxygen demand. The present study demonstrates that washing and sanitizing chicken transport cages reduces, but does not completely eliminate, bacterial contamination on the flooring surface. 相似文献
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利用天然藏青果提取物中的多酚成分能与甲醛发生化学反应的原理,制备具有除甲醛功能的真丝织物。采用正交试验优化制备工艺条件为:整理温度70℃,整理时间2.0 h,整理液pH 4。在此工艺条件下,用质量分数为8%的藏青果提取物粉末整理制备的真丝织物24 h对空气中甲醛的去除率可达到84.5%,较普通真丝织物对空气中甲醛的去除率提高74.7个百分点。进一步用金属离子处理真丝织物,可有效改善织物除甲醛功效的耐洗性能,其中:Fe2+离子处理织物经10次洗涤后,甲醛去除率仅下降5.2个百分点;Al3+离子处理后,甲醛去除率仅下降4.9个百分点。试验表明,利用藏青果提取物整理及金属离子后处理制备的真丝织物具有明显的除甲醛功效,且织物的耐洗性能良好,是一种新型健康环保的织物。 相似文献