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51.
Cauda epididymal spermatozoa were obtained from testicles collected from abattoir(s). The pooled sperm samples were divided into four aliquots. Each aliquot was washed separately with the buffer of respective extender and finally extended with the four extenders viz. egg yolk–citrate (EYC), egg yolk–citrate–fructose (EYCF), Tris–citric acid–egg yolk–fructose (TCEYF) and egg yolk–Mcillvaine glucose (EYMG) and preserved at 4°C. The per cent sperm motility for EYC, EYCF, TCEYF and EYMG at 0 h was 50.83%, 56.67%, 75.00% and 31.67%, respectively, and at 72 h was 24.17% (EYC), 30.83% (EYCF), 51.67% (TCEYF) and 7.50% (EYMG). The corresponding figures for live sperm count at 0 h was 83.17%, 86.33%, 90.42% and 81.75% and at 72 h was 64.75%, 73.92%, 76.00% and 57.67%. The corresponding figures for mean per cent intact acrosome at 0 h was 95.33%, 95.50%, 90.92% and 97.25% and at 72 h was 86.17%, 83.92%, 77.58% and 86.33%. The sperm motility was significantly (p < 0.05) higher for TCEYF at different h of preservation from 0 h through 72 h. The sperm motility, live sperm count and per cent intact acrosome declined significantly (p < 0.05) with the advancement of storage time in all the four extenders. Our study concluded that TCEYF was best out of the extenders studied for preservation of cauda epididymal spermatozoa after double centrifugation and extension at 4°C up to 72 h of preservation. However, EYCF also has better potential for the preservation of cauda epididymal spermatozoa as viability was in close proximity and acrosomal integrity was higher compared with TCEYF extender.  相似文献   
52.
53.
Development of leaf rust (Melampsora ciliata) in different species, hybrids and cultivars of poplar (Populus spp.) was studied in nursery‐grown plants. Five different criteria were used to assess the disease development. The mean disease index on 10 August was 9.4% which increased to 70.0% on 10 October. The lowest disease index (5.5%) was recorded in P. yunnanensis whereas the maximum was recorded in P. × euramericana‘Rubra‐Poiret’ (59.5%). The apparent infection rate per unit per day was highest in P. nigra × P. trichocarpa (9.7 × 10–2) whereas the minimum occurred in P. maximowiczii × P. berolinensis‘Oxford’ (3.3 × 10–2). The area under the disease progress curve was a maximum in P. × euramericana‘Rubra‐Poiret’ (26.7) and a minimum in P. yunnanensis (1.6). Complete defoliation by the first half of October occurred in P. nigra × P. trichocarpa, which also had the maximum apparent infection rate and area under the disease progress curve. Inoculum production was highest in P. nigra × P. trichocarpa and lowest in P. maximowiczii × P. berolinensis‘Oxford’.  相似文献   
54.
The predatory mite Typhlodromus pyri Scheuten (Acari, Phytoseiidae) has been reported as an important predator of the European red mite, Panonychus ulmi (Koch) (Acari, Tetranychidae) in apple culture and vineyards at below 25?°C. However, sufficient biological data was lacking on its efficiency at temperatures above 25?°C. Therefore, the purpose of the present laboratory work was to obtain experimental data on prey consumption during development as well as longevity and reproduction of T. pyri on apple leaf discs and in Plexiglas cells at constant temperatures of 25?±?2?°C and 30?±?2?°C with P. ulmi as prey.  相似文献   
55.

Background

The primary aims of this study were to determine the incidence of Giardia infections in dairy herds on farms in the New York City Watershed region and to evaluate risk factors associated with infections. Because co-infections of Giardia and Cryptosporidium spp. are common in this population, we also evaluated the effect of herd infection status on Giardia infections.

Methods

Farms were grouped into three cohorts based on their prior infection status with Giardia and/or Cryptosporidium spp. The sampling plan included collecting fecal samples from all calves below 30 days of age and proportional sampling of calves, young stock, and adults. A total of 10,672 fecal samples were collected and analyzed for the presence of Giardia cysts using zinc sulfate flotation. Herds enrolled in the study were sampled seasonally for a study period of two years. The probability of shedding cysts past a certain age and the factors that influenced the likelihood of shedding were evaluated using survival analysis. Linear regression was used to evaluate factors that were associated with the intensity of shedding.

Results

The majority of Giardia infections occurred in calves within their first 180 days of age, with the most number of calves shedding Giardia cysts between 11 and 20 days of age. The incidence of shedding of Giardia cysts ranged from 0.0004 per animal day for cattle in the low risk cohort to 0.0011 per animal day for cattle in the high risk cohort. The likelihood of shedding was influenced by the prior infection status of the herd and the season of collection. Infected animals shed on average 9,658 cysts/gram and the intensity of shedding Giardia cysts varied significantly with the age (p < 0.0001) and the season of collection (p = 0.0151 for Spring).

Conclusion

Giardia infections are common in dairy herds in the New York City watershed, particularly in calves less than 6 months of age. Seasonality may be an important factor in the perpetuation of infections based on changes in management practices corresponding to weather patterns of a particular season. A dairy herd''s prior infection status with Cryptosporidium influences the likelihood of infection with Giardia.  相似文献   
56.
Proteomic analysis of mare uterine flush fluid provides a minimally invasive technique for studying protein changes associated with the oestrous cycle. The aim of this study was to identify differentially abundant proteins in the uterine flush fluid of mares in oestrus and dioestrus. In this study, uterine flush fluid samples were collected from eight reproductively healthy mares in either oestrus (n = 5) or dioestrus (n = 3). Proteomic analysis was performed using liquid chromatography‐tandem mass spectrometry. Of 172 proteins identified, six proteins (immunoglobulin lambda‐like polypeptide 1, haemoglobin subunit alpha, alpha‐1B‐glycoprotein, serotransferrin, apolipoprotein A‐1, and haemoglobin subunit beta) were significantly more abundant in oestrus. These proteins may contribute to the endometrial defence system through roles in inflammation, immunity or antimicrobial activity. In other species, some of these proteins have been described as immunoglobulins, negative acute phase proteins or defence agents against micro‐organisms. During dioestrus, immunoglobulin alpha‐1 chain C region‐related, complement factor I, CD 109 antigen and uterocalin, were significantly more abundant. Research in other species suggests that these four proteins contribute to the immune response through proposed immunoregulatory characteristics, complement system involvement or roles in B cell–T cell interactions. In conclusion, ten differentially abundant proteins were identified in the uterine flush fluid of mares in oestrus and dioestrus. Targeted studies on these proteins could elucidate their role in uterine defence mechanisms during the oestrous cycle in the mare.  相似文献   
57.
Objective: To correlate the sodium chloride dosage and the serum sodium concentration to clinical signs, to determine if the dosage of homemade play dough (and, therefore, sodium chloride) is the most reliable way to predict clinical signs and prognosis, and to review previously reported treatment options. Design: Retrospective case series. Animals: Fourteen dogs with a history of homemade play dough ingestion. Procedure: Cases were examined for each animal's signalment including body weight, age, approximate amount of play dough ingested, the estimated sodium chloride dosage, clinical signs, serum sodium concentration, and outcome when available. The literature was reviewed to determine pathophysiology and treatment regimens. Results: Twelve of 14 dogs (86%) that ingested homemade play dough showed clinical signs. Vomiting (9 of 14, 64%), polydipsia, and seizures (4 of 14 each, 29%) were the most common signs followed by polyuria, tremors (3 of 14 each, 21%), and hyperthermia (2 of 14, 14%). The lowest calculated dosage associated with objective clinical signs was 1.9 g/kg. Seizures were reported in all animals with serum sodium levels greater than 180 mEq/L. Conclusions and clinical relevance: Homemade play dough ingestion can be a serious and life‐threatening problem. Many factors can contribute to the toxicity of homemade play dough. This study indicates that the serum sodium concentration is a more reliable indicator of the clinical course of the toxicity rather than the amount of play dough and, therefore, the dosage of sodium chloride ingested. Treatment should be based on a clinical evaluation of the patient and laboratory results, and consists of controlling seizures, reducing serum sodium concentrations slowly, and supportive care.  相似文献   
58.
应用多重PCR检测人工感染鸡呼吸道疾病的研究   总被引:3,自引:0,他引:3  
本文报道了IBV,NDV,ILTV,MG人工感染4周龄SPF鸡和非免疫鸡后,用多重PCR检测试验鸡的咽喉棉拭子和器官组织样品,并与传统的病原分离鉴定,血清学方法进行比较,多重PCR无论是对单一感染病原,还是对两种以上混合感染病原,其敏感性和检测速度都优于传统的鉴别诊断方法,具有较高的实用价值,可以直接应用于临床检测,服务于生产。  相似文献   
59.
The spike 1 (S1) surface glycoprotein of infectious bronchitis virus (IBV) is the major inducer of the generation of virus neutralizing antibodies, and the administration of purified S1 has been shown to elicit a protective immune response against virulent virus challenge. On the basis of these observations, recombinant fowl poxvirus (rFPV) containing a cDNA copy of the S1 gene of IBV Mass 41 (rFPV-S1) was constructed and its immunogenicity and vaccine potential were evaluated. Initially, rFPV-S1 was shown to express the S1 in vito by indirect immunofluorescence staining and western blot analyses. Later, in vivo expression was demonstrated by the detection of IBV-specific serum immunoglobulin G and neutralization antibodies in the sera of chickens immunized with rFPV-S1. That the recombinant virus elicited anti-IBV protective immunity was indicated by the manifested, relatively mild clinical signs of disease, decreased titers of recovered challenge virus, and less severe histologic changes of the tracheas in virulent IBV Mass 41-challenged chickens previously receiving rFPV-S1 as compared with parental fowl poxvirus (FPV)-vaccinated control birds. In contrast, chickens immunized with either recombinant or parental FPV were resistant to a subsequent virulent FPV challenge. As to a preferred method of immunization, wing web administration appeared to be superior to the subcutaneous route because a greater percentage of birds vaccinated by the former protocol exhibited an anti-IBV humoral immune response. Thus, rFPV-S1 has potential as a poultry vaccine against both fowl pox and infectious bronchitis.  相似文献   
60.
Summary To elaborate on off-flavour development in dehydrated potato granules, lipids in subcellular particles and membrane systems of the tuber were investigated. Lipid acyl-hydrolase and lipoxygenase activities were suppressed in tuber homogenates by a buffer isolation medium of pH 7.8 containing nupercaine which minimized the breakdown of phospho- and galactolipids. Phospholipid, glycolipid and neutral lipid constitutents, their fatty acid composition, and unsaturation ratios were reported for amyloplasts, cell wall, microsomes, mitochondria, peroxisomes, and plasmalemma.
Zusammenfassung Analysen von Kartoffelknollen wurden durch lipidabbauende Enzyme, Lipidacylhydrolase (LAH) und Lipoxygenase (LOX) behindert. Die LOX-Aktivit?t in handelsüblicherzugten Kartoffeln war hoch (Tabelle 1) und konnte durch gew?hnliche Inhibitoren nicht beeinflusst werden (Tabelle 2). Die LAH-Aktivit?t, die mit Phospholipiden (PL) und Galactolipiden als Substrate hoch war, wurde durch Nupercaine in verschiedenem Ausmass unterdrückt (Tabelle 3), dessen Weglassung w?hrend der Lipidanalyse von Kartoffelmembranen und subzellularen Partikeln hohe Lipidverluste verursachen k?nnte (Tabelle 4). Lipidergebnisse für mikrosomale Pr?parate, Mitochondrien, Peroxisomen, Plasmalemmen und St?rkek?rner (Tabellen 5–9) wurden wiedergegeben: nach Isolation bei pH 7,2, wenn die LOX-Aktivit?t nicht gehemmt war (Verfahren A); in einer Puffersubstanz von pH 7,8 ohne Nupercaine, wenn wohl die Aktivit?t von LOX unterdrückt war, nicht aber jene von LAH (Verfahren B); und bei pH 7,8 mit Nupercaine, wenn die Aktivit?t beider Enzyme unterdrückt war (Verfahren C). In den meisten Analysen zeigte die Lipidzusammensetzung, wenn die Aktivit?t beider Enzyme nicht unterdrückt wurde, eine entsprechende Anreicherung von PL, Sterollipiden und freien Fetts?uren (FFA) und ihrer Abbauprodukte sowie eine Abnahme im Gehalt an Galactolipiden. Kleine Mengen von Lipiden wurden in Form von Lipidpartikeln und verbunden mit Knollenzellw?nden gefunden (Tabelle 10). Die Fetts?urezusammensetzung des Gesamtlipids und einige besondere Lipidbestandteile und ihr Nichts?ttigungsverh?ltnis (UR) wurden nur für Verfahren C berechnet. Wenn dieses Verfahren weggelassen wurde, wie dargestellt mit Hilfe der St?rkelipid-Zusammensetzung, ergab sich nicht nur ein Verlust von Membran-PL und Galactolipiden. Fast die H?lfte der zurückgebliebenen neutralen Lipidfraktion war in Form von FFA in verschiedenen Graden oxydiert (Tabelle 9). Das UR der Gesamtlipide (TL) schwankte zwischen 0,4 und 2,9. Es war niedrig in der Zellwand, h?her im Plasmalemma und am h?chsten innerhalb der Zytoplasmamembranen. Das UR nahm dann bei den Vacuolen mit St?rkek?rnern ab. Die Bedeutung der Ergebnisse für die Bestimmung der Funktion von Lipiden in einem handelsüblichen Verfahren zur Herstellung von Püreepulver wirdt diskutiert.

Résumé La dégradation enzymatique des lipides par la lipide acyl hydrolase (LAH) et par la lipoxygénase (LOX) génait l’analyse biochimique des tubercules de pomme de terre. L’activité de la LOX était importante dans les pommes de terre cultivées pour la commercialisation (tableau 1) et n’était pas affectée par les inhibiteurs courants (tableau 2). L’activité de la LAH, qui était forte avec les phospholipides (PL) et les galactolipides, était inhibée sur différents substrats par la nuperca?ne (tableau 3); l’absence de cette dernière durant l’analyse de la membrane et des organites intracellulaires du tubercule causait de fortes pertes en lipides (tableau 4). Les résultats obtenus avec les lipides des préparations de microsomes, mitochondries, peroxysomes, plasmalemme et de grains d’ amidon (tableaux 5 à 9) sont exposés; après isolement à pH 7,2 sans inhibition de l’activité de la LOX (procédé A); dans une solution tampon à pH 7,8 sans nuperca?ne alors que l’activité de la LOX est inhibée mais non celle de la LAH (procédé B); et à pH 7,8 avec nuperca?ne et inhibition de l’activité des deux enzymes (procédé C). Dans le cas où l’activité des deux enzymes n’était pas inhibée, la composition en lipides montrait un enrichissement relatif en PL, stérols, acides gras libres (FFA) et en leurs produits de dégradation ainsi qu’une diminution de la teneur en galactolipides. Une petite quantité de lipides était retrouvée sous la forme de particules lipidiques associées aux membranes cellulaires (tableau 10). L’étude de la composition en acides gras des lipides totaux et de quelques constituants lipidiques ainsi que la mesure de leur taux d’insaturation (U.R.) ont été effectuées seulement pour le procédé C. Quand ce procédé n’était pas employé, comme l’illustre la composition en lipides de l’amidon, il y avait non seulement une perte de PL et galactolipides membranaires mais la moitié de la fraction lipidique neutre retenue se trouvait sous la forme de FFA oxydés à différents degrés (tableau 9). L’U.R. des lipides totaux (TL) variait de 0,4 à 2,9; il était bas dans les membranes cellulaires, plus élevé dans le plasmalemme et le plus haut dans les membranes cytoplasmiques. L’U.R. diminuait dans les vacuoles contenant des grains d’amidon. L’intérêt de cette découverte pour la détermination des lipides au cours de la fabrication industrielle de granules de pomme de terre est discuté.
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