首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
For the moment the agents that are used against Botrytis cinerea, in glasshouses were tomatoes are cultivated, are from chemical origin. For reducing the use of chemical agents in the future it is important to search for effective biological control agents against the fight of Botrytis cinerae. The following biological products Vital pasta, Vital gel and Elot-Vis were examined in there possibility to control Botrytis cinerea. Elot Vis was tested out in experiments that were carried out in climate chambers were leafs of 3 week old tomato plants were artificially infected with Botrytis cinerea spores. Also the biological products of Vital were first investigated in experiments that were carried out in climate chambers. In stead off leafs of tomato plants it were stem wounds of tomato plants who were treated with the pasta or the gel that was spread over the wounded surface after this has been inoculated with a suspension of conidia of Botrytis cinerae. The results of these first tests that were executed in the climate chambers were the circumstances for Botrytis cinerea were ideal seemed promising. In the next step these products were tested out on large scale in glasshouses. For each plant 5 wounds were created by removing the leafs, these wounds were or first treated with the Biological product and thereafter artificially infected with Botrytis cinerea spores to check out if these products can be used as a preventive agent or the wounds were first inoculated with a suspension of Botrytis cinerea spores and thereafter treated with the product. For the product Elot-Vis a few plants were totally sprayed with an Elot-Vis suspension before leafs were removed and the wounds were inoculated with conidia of Botrytis cinerea to check out if this product was able to activated the induced systemic resistance pathway. The experiments that were executed in glasshouses showed different percentages of succeeded Botrytis cinerea infections. This is probable due to the different weather conditions during both days that the experiments were executed. For the wounds that were treated with pasta it was difficult to distinguish wounds were Botrytis cinerea succeeded to infect the plant, because these wounds frequently didn't show any sign of infection on the surface but when the wounds with the pasta were cut open it was possible to see Botrytis cinerea infections inside the stem.  相似文献   

2.
S Ohno 《Histochemistry》1985,82(6):565-575
Synthesized N protein of vesicular stomatitis virus (VSV) is associated with replicated viral genomes in the infected cells. The cytoplasmic side of cell membranes was examined by quick-freezing and deep-etching replica method, in order to clarify the localization of VSV genomes. Control or infected monolayer Vero cells were fixed in 2% paraformaldehyde, scraped and centrifuged to make pellets. A drop of the cell pellet was put between two glass coverslips, which were coated with 3-aminopropyl triethoxy silane and glutaraldehyde. The cells were consequently split open and postfixed in the mixture of glutaraldehyde and paraformaldehyde. Some inside-out cell membranes on the coverslips were immunostained with anti-N monoclonal antibody directly coupled to gold particles. Others were immunostained with anti-N monoclonal antibody and rabbit anti-mouse IgG coupled to peroxidase and fixed again in glutaraldehyde. They were incubated in diaminobenzidine and hydrogen peroxide solution for 1 min. All of them were infiltrated with 10% methanol in distilled water and quickly frozen in a mixture of isopentane and propane cooled by liquid nitrogen. Such preparations were deep-etched and shadowed by platinum and carbon. Although many cell organelles were found to be associated with the cytoplasmic side of cell membranes in the normal Vero cells, few cell organelles were attached to it in the infected cells. On the contrary, special strand structures were identified, which could be immunostained with anti-N monoclonal antibody. It is concluded that platinum replicas have sufficient resolution to identify the VSV genomes coated with N protein and that these nucleocapsids can be associated with the cytoplasmic side of cell membranes in the infected cells.  相似文献   

3.
This study was designed to determine conception rates in dairy cows after timed-insemination and simultaneous treatment with gonadotrophin releasing hormone (GnRH) and/or prostaglandin F2 alpha (PGF2alpha). A total of 2352 cows was randomly assigned to six groups. Cows in Groups 1 to 5 were palpated per rectum to determine the presence of a corpus luteum (CL) on the ovary, and blood samples were obtained for the determination of plasma progesterone (P4) concentrations. Cows with a CL and P4 concentrations >1 ng/ml were treated (Day 0) with PGF2alpha (25 mg, i.m.) and were observed for estrus. Cows in estrus prior to 72 hours after treatment (Group 5, n = 106) were bred, but were not treated. Cows not observed in estrus by 72 hours were divided into four remaining groups, were bred between 72 and 80 hours and were assigned as follows: Cows in Group 1 (n = 203) were not treated; Cows in Group 2 (n = 200) were treated with GnRH (100 ug, i.m.); Cows in Group 3 (n = 201) were treated with PGF2alpha (25 mg, i.m.); and cows in Group 4 (n = 202) were treated with both GnRH and PGF2alpha. Cows in Group 6 (n = 1440) were not treated with PGF2alpha on Day 0 and were estrual cows that were bred on days when cows in Groups 1 to 5 were time-inseminated. The percentage of cows in all groups pregnant at 45 to 50 days after one insemination was compared using analysis of variance (P<0.05). The conception rate of cows in Group 2 was significantly higher than that of cows in Groups 1 to 4. There was a significant group-by-season interaction. Cows treated with GnRH during the spring had a higher conception rate than at other times of the year. Conception rates of cows in Groups 1 to 4 that were inseminated during the summer were low and not significantly different from each other. Conception rates of cows in Groups 5 and 6 inseminated during the summer were not significantly different from each other, but were significantly higher than that of cows in Groups 1 to 4 that were inseminated during the summer.  相似文献   

4.
AIMS: To determine the effect of antimicrobial selective pressure on the transmission of antimicrobial resistant and sensitive strains of Salmonella in poultry. METHODS AND RESULTS: Eight pens housed 12 broiler chicks each. Two chicks in four of the pens were inoculated with a Salm. Typhimurium strain resistant to 12 antimicrobials (including tetracycline), and two chicks in each of the four other pens were inoculated with a strain sensitive to all antimicrobials tested. Two pens inoculated with each strain were treated with chlortetracycline and two were not. Chicks were killed on day 7 and caeca were cultured for Salmonella. Experiments were performed independently twice. Chicks exposed to pen mates inoculated with the resistant strain and treated with tetracycline were 90% positive for Salmonella; whereas 60% of chicks given no antimicrobials were positive. Chicks exposed to the sensitive strain were 95% positive with tetracycline treatment and 90% positive without treatment. CONCLUSIONS: A multidrug-resistant Salm. Typhimurium strain had significantly increased transmission when chicks were treated with tetracycline. Transmission of a sensitive strain was not inhibited by antimicrobial selective pressure at recommended therapeutic dose. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrates that antimicrobial usage may influence the transmission of antimicrobial-resistant pathogens in poultry.  相似文献   

5.
汶川地震对大熊猫主食竹——拐棍竹竹笋生长发育的影响   总被引:1,自引:0,他引:1  
廖丽欢  徐雨  冉江洪  郑雯  缪宁  尚涛 《生态学报》2012,32(10):3001-3009
为了了解汶川地震对大熊猫主食竹生长发育的影响,2009年10月—2011年4月,在地震重灾区四川龙溪-虹口国家级自然保护区内设置150个样方,就地震强度、中度、轻度干扰对大熊猫主食竹拐棍竹(Fargesia robusta)竹笋生长发育的影响进行了研究。研究结果显示:(1)发笋物候上,地震强度干扰的发笋时间(Julian时间)较中度和轻度干扰显著推迟,而发笋期不受影响。(2)发笋量和当年生幼竹数是拐棍竹更新生长的数量指标。地震强度和中度干扰样方的发笋量都显著高于轻度干扰,而发笋量在强度和中度干扰间差异不显著;地震强度干扰样方的当年生幼竹数显著高于中度和轻度干扰,中度和轻度干扰样方间差异不显著。这说明地震的强度和中度干扰都有利于拐棍竹竹笋和当年生幼竹数量的更新。(3)基径和株高是拐棍竹更新生长的质量指标。强度干扰下拐棍竹的基径和株高都显著小于中度和轻度干扰,中度干扰样方的基径与轻度干扰差异不显著,但株高显著矮于轻度干扰样方。表明强度干扰下拐棍竹的质量最差,中度干扰的基径已基本得到恢复,但株高仍受到抑制。(4)地震不同干扰等级拐棍竹退笋原因划分为:外力机械损伤、动物取食、生长停止、其他4种。对地震不同干扰等级拐棍竹退笋原因比率的分析发现,强度干扰样方因外力机械损伤和生长停止退笋的比率显著高于中度和轻度干扰样方,而因动物取食退笋的比率显著低于中度和轻度干扰样方。证明强度干扰样方的竹笋更容易受到外力机械损伤和生长停止退笋,而中度和轻度干扰的竹笋更倾向于动物取食致退,揭示了拐棍竹的生长是与震后不同程度的干扰相适应的。  相似文献   

6.
Polychrome-stained equine synovial fluid specimens from 34 normal joints and 129 joints with clinical abnormalities were examined cytologically. The smears from joints with abnormalities were categorized as within normal limits (4.7%), slight abnormality (27.9%), proliferative synovitis (21.7%), neutrophilic pattern (20.2%), elongated cell pattern (10.1%), other moderate to marked abnormality (11.6%) and unsatisfactory (3.9%). Cytologic abnormalities that were not restricted to a single category included spindle cells, crystals, stellate cells and cartilage fragments. Multinucleate cells and mononucleate cells with dense cytoplasm and a delicate periphery were seen in smears from cases with clinical diagnoses of osteochondrosis or fracture; interpretation of these cells as osteoclasts and their mononucleate precursors was supported by positive staining with tartrate-resistant acid phosphatase. Smears within the same cytologic category were not found to correspond with a single clinical diagnosis. The identification of several cytologic patterns in cases with the same clinical diagnosis suggests that multiple stages of disease were sampled. Except in cases with the cytologic neutrophilic pattern, there was not a consistent relationship between the histologic features in synovial biopsy specimens and the cytologic findings; the morphologic variation within synovial membrane sections and between sections from different locations was sometimes marked. When compared with air-dried, Wright-Giemsa-stained smears, the polychrome-stained smears were more sensitive in the detection of cytologic abnormalities and were less often falsely negative or unsatisfactory. Following surgery, cases with clinical diagnoses of osteochondrosis (29 cases) and fracture (25 cases) were analyzed according to clinical outcome and cytologic category. While 80% of the horses with proliferative synovitis in cytologic specimens were sound, only 67% of those with the elongated cell pattern, 50% of those with slight abnormality and 33% of those with other moderate to marked abnormality were sound. A statistically significant relationship (P less than .02) was found in cases with a diagnosis of osteochondrosis: animals with a proliferative synovitis pattern were almost three times as likely to be sound as compared to those with slight abnormality. These findings indicate that polychrome-stained equine synovial fluid smears (1) provide information that is different from that found in corresponding histologic sections and (2) are superior to air-dried, Wright-Giemsa-stained smears for cytologic examination. The polychrome-stained equine synovial fluid smears were found to provide information supportive of clinical, radiographic and prognostic data.  相似文献   

7.
The injection of neonatal mice with phenylalanine resulted in a rapid decrease in brain polyribosomes and a concomitant increase in monomeric ribosomes. Animals of 1-16 days of age were equally affected by phenylalanine, although the brain polyribosomes of 60-day-old mice were relatively resistant to the effects of phenylalanine. The population of free polyribosomes appeared to be more sensitive to phenylalanine treatment than bound polyribosomes, which were somewhat more resistant to disruption by high concentrations of the amino acid. The effects of phenylalanine were more pronounced with polyribosomes in the cerebral cortex than with those in the cerebellar tissue. The mechanism of polyribosome disruption was shown to be independent of hydrolysis mediated by ribonuclease. Virtually all of the monomeric ribosomes that resulted from phenylalanine treatment were shown to be inactive with regard to endogenous protein synthesis and were present in the cell cytoplasm as vacant couples. These ribosomes were readily dissociated by treatment with 0.5 M-KCl and subsequent ultracentrifugation. These results are discussed in the light of the possibility that high concentrations of phenylalanine disrupt brain protein synthesis by a molecular mechanism that is associated with initiation events.  相似文献   

8.
Rat liver nuclear ribonucleoprotein particles were prepared by two different methods and defined as 40S ribonucleoprotein (40S RNP) and heterogeneous nuclear ribonucleoprotein (HnRNP) particles. The RNP particles were either solubilized in 8 M urea--6 mM 2-mercaptoethanol--20 mM glycine--20 mM Tris--HCl (pH 8.4) or subjected to removal of RNA by phenol extraction prior to solubilizing the proteins in the urea buffer. The proteins associated with 40S RNP and HnRNP were heterogeneous and very similar in their electrophoretic patterns when analyzed by two-dimensional PAGE, except a protein with molecular weight of 62 000 and an isoelectric point (pI) of 6.2 was present only in HnRNP particles. At least 12 major and 22 minor components could be identified in both preparations. The major proteins were found at pI values varying from 6.0 to 8.5 and with molecular weights from 32 000 to 42 000, and a group of proteins with molecular weight approximately 65 000 were more prominent in HnRNP than in 40S RNP. The other components were found mainly at pI ranges from 5.0 to 6.5 with molecular weights from 43 000 to 65 000. The phenol method extracted essentially all proteins associated with either 40S RNP and HnRNP, but was less effective in extracting a group of proteins with pI values from 5.0 to 5.5 and more efficient for proteins with pI values from 7.5 to 8.5. When chromatin proteins isolated by phenol extraction were compared with HnRNP particle proteins isolated by the same method, the electrophoretic mobilities of the HnRNP particle proteins were found to be identical with a fraction nonhistone chromatin proteins. The 40S RNP particles were further purified by metrizamide isopycnic density gradient centrifugation. The electrophoretic patterns of these proteins were very similar to those prepared by sucrose density gradient centrifugation. Therefore, we concluded that the proteins of RNP particles constituted part of the chromatin proteins.  相似文献   

9.
Eighteen mature estrous cycling beef cows and 9 prepuberal heifers were stratified by breed, age and weight to determine the effect of ovary-transplantation to a proximal site (right uterine horn) (U) and distal site (parotid region) (P) upon ovarian activity. Active ovaries (AO), ovaries with the corpus luteum (CL), were autotransplanted to the myometrium of the U in 3 cows and to the muscles of the P in 2 cows and their inactive ovaries (IO), ovaries without a CL, remained. Active ovaries of 6 cows were removed and heterotransplanted to 6 prepuberal heifers and their 10 were heterotransplanted to the U or the parotid (3). Six heifers received either a mature AO in the U or in the parotid. Three heifers were ovariectomized and their ovaries were heterotransplanted to 6 cows, 3 per site. Cows and heifers were slaughtered randomly 2 months after surgery and their ovaries were collected for microscopic and histological analysis. The transplants were successfully accomplished in 94% of the cows and in 83% of the heifers. Both of the unsuccessful heterotransplantations were located in the uterus. More estrous activity was found (P<.025) in cows than in heifers with their own ovaries in situ . All prepuberal ovaries in situ showed follicular development when mature AO were transplanted to either the U or parotid. The same trend was found in prepuberal ovaries transplanted to mature cycling cows. Cows with an IO in situ and AO transplanted to either site had more estrous activity than did ovariectomized cows with an IO transplanted to either site. Pregnancy rates in mature cycling cows with an least one ovary in situ were higher (P<.005) in cows with an ovary in the parotid region than cows with an ovary transplanted to the uterus.  相似文献   

10.
Several studies on aneuploidy and aging have shown a significant increase in the loss of chromosomes in both males and females with age. Others have observed a significant increase in micronucleus formation in lymphocytes with age. The objectives of this investigation were to determine the relationship between sex chromosome loss and increased micronucleus frequencies with age, to establish sex chromosome loss frequencies unbiased by cellular survival factors or slide preparation, and to determine the effect of smoking on sex chromosome loss. Blood samples were obtained from 8 newborn females and 38 adult females ranging in age from 19 to 77. Isolated lymphocytes were cultured according to standard techniques and blocked with cytochalasin B. Two thousand binucleated cells per donor were scored using a modified micronucleus assay to determine the kinetochore status of each micronucleus. Slides were then hybridized with a 2.0 kb centromeric X chromosome-specific probe labeled with biotinylated dUTP, and detected with fluorescein-conjugated avidin. All micronucleated cells were relocated and their X chromosome status was determined. We found the X chromosome to be present in 72.2% of the micronuclei scored; additionally our results show a significant increase with age in the number of micronuclei containing an X chromosome.  相似文献   

11.
Pathogenicity of mouse hepatitis virus for preimplantation mouse embryos   总被引:1,自引:0,他引:1  
Mouse embryos which were hatched from the zona pellucida in vitro in the presence of mouse hepatitis virus (MHV) or outgrown on coverslips and then exposed to MHV were shown by immunohistochemical staining to have virally infected trophoblast cells. Zona-intact embryos incubated with MHV for 48 h (2-cell embryos) or 1.5 h (blastocysts) were resistant to infection. Morulae and early blastocysts collected from donor mice experimentally infected with MHV were not infected, but the medium in which they were flushed from the uterine horns was contaminated with virus. No virus was detected after embryos were washed through three changes of uncontaminated medium. MHV was transmitted to foster mothers when embryos were transferred in medium contaminated with the virus. Fetal and decidual tissues were not infected. We suggest that embryo transfer is an effective and simple alternative to Caesarian rederivation of MHV-contaminated mice.  相似文献   

12.
The parents of children with life threatening or terminal illnesses were interviewed about their experiences of the way in which they were told the diagnosis. The interview was piloted on 25 families and then administered in a semistandardised manner to a further 45 families. Parents were asked how satisfied they were with the initial discussion about the diagnosis: 23 families were satisfied with how much information they were given; 22 with the information concerning prognosis; 20 with the pacing of the information; 33 with who was present; 32 with arrangements for follow up; and 26 were satisfied overall with the initial discussion. Clear patterns emerged about which elements of the discussion parents appreciated or resented. For example, they valued an open, sympathetic, direct, and uninterrupted discussion of the diagnosis in private that allowed sufficient time for them to take the news in and for doctors to repeat and clarify information. They disliked evasive or unsympathetic brief interviews. All parents remembered vividly the manner in which the diagnosis was imparted, and some were still preoccupied with this many years later. Analyses were carried out to test the possibility that reports of satisfaction and dissatisfaction were a function of current depression and anxiety, but no evidence was found for this.  相似文献   

13.
Slices of rat livers were incubated with 14C amino acids, homogenized, and subjected to differential centrifugation. The microsomes were further extracted with the non-ionic detergent Lubrol W and with EDTA. These extracts and the microsome free "cell sap," freed from the pH 5 precipitable fraction, were subsequently reacted with antisera using agar diffusion techniques. The antisera employed were obtained from rabbits injected with different subcellular fractions of rat liver or with rat serum proteins. When the agar diffusion plates were autoradiographed it was found that some of the precipitates were radioactive while others were not. Control experiments indicated that this labeling was due to the specific incorporation of 14C amino acids into various rat liver antigens during incubation of the slices rather than to a non-specific adsorption of radioactive material to the immunological precipitates. When the slices were incubated with the isotope for up to 30 minutes, the serum proteins which could be extracted from the microsomes with the detergent were strongly labeled, as were a number of additional microsomal antigens of unknown significance. In contrast, the serum proteins present in the cell sap were only weakly labeled. Most of the typical cell sap proteins, both those precipitable and those soluble at pH 5, seemed to remain unlabeled. No consistently reproducible results were obtained with the EDTA extracts of the ribosomal residues remaining after extraction of the microsomes with the detergent. Incubation of the liver slices for longer periods (up to 120 minutes) led to a strong labeling of the serum proteins in the cell sap as well as to the appearance of labeling in additional cell sap proteins. The results are discussed with regard to the subcellular site of synthesis and the metabolism of the different antigens.  相似文献   

14.
BACKGROUND AND AIMS: Intervascular pit membranes were examined within Ericales to determine the distribution and structure of torus-like thickenings. METHODS: Forty-nine species representing 12 families of the order Ericales were investigated using light, scanning and transmission electron microscopy. They were compared with four species of Oleaceae to determine the true nature of the thickenings. KEY RESULTS: Pit membranes with torus-like thickenings were observed in seven species of Ericaceae and were found to be amorphous, plasmodesmata-associated structures with an irregular distribution. These pseudo-tori show major differences compared with true tori with respect to their distribution and ultrastructure. Genuine tori, which are strongly correlated with round pit apertures in narrow tracheary elements, were found in two species of Osmanthus (Oleaceae). CONCLUSIONS: The pseudo-tori found in some Ericaceae are considered to be similar to pit membrane thickenings previously recorded in Rosaceae. While true tori appear to be functionally significant in terms of efficiency and safety of water transport, the possible function of pseudo-tori could be associated with the role of plasmodesmata during differentiation of tracheids, fibre-tracheids or narrow vessels.  相似文献   

15.
A M Dhople 《Microbios》1991,66(266):55-64
The activities of hydrolytic enzymes in various organs of armadillos infected with Mycobacterium leprae were compared with those in normal armadillos. Except for aspartate aminopeptidase and esterase, the levels of the other enzymes in liver, spleen and inguinal lymph nodes were significantly higher in armadillos infected with M. leprae compared with those in non-infected ones. These enzymes levels were at a maximum when the animals were sacrificed 22 to 30 months post-inoculation, a period when the bacterial load in the animals had also reached a maximum. Animals infected with M. leprae but not showing any signs of disseminated infection behaved similar to those in the non-infected group. The observed changes in enzymatic activities were not due to bacterial enzymes and so can be related to tissue damage caused by M. leprae.  相似文献   

16.
Plants can be genetically engineered for virus resistance by transformation with a viral gene. We transformed tobacco with the tomato spotted wilt virus (TSWV) nucleocapsid gene from the Hawaiian L isolate in order to obtain TSWV resistant breeding lines. Doubled-haploid lines were produced from primary transgenic plants that were selected for resistance to the virus. Several of these lines showed very high levels of resistance and were symptomless after inoculation with the Hawaiian L isolate of TSWV. The accumulation of only low levels of full-length transgene RNA and protein observed in these lines is consistent with an RNA-mediated mechanism of resistance. The lines that were highly resistant to the Hawaiian L isolate of TSWV were also found to be highly resistant to several other isolates of TSWV, while lines that were only moderately resistant to the Hawaiian L isolate were often susceptible to the other isolates. The highly resistant lines were advanced over several generations by self-pollination. Although these lines were fully homozygous, several lines lost resistance in later generations, indicating that the resistance was unstable. Selection for resistance in these unstable lines did not prevent the occurrence of susceptible progeny in subsequent generations. Therefore, testing over several generations is required to determine the stability of resistance when breeding crops with transgenic virus resistance.  相似文献   

17.
Male Periplaneta americana were photographed in a 2.4 m diameter arena containing a female sex pheromone source in the centre. Orientation pathways were digitized and analysed with regard to chemo-orientation mechanisms employed. Indirect components of chemo-orientation include arrestment near the pheromone source owing to an increase in turning rate and decrease in rate of locomotion, and zig-zag motor patterns that facilitate localization of the source. Most males were successful in locating the source if they moved to within 30 cm. Direct components of chemo-orientation include looping and relatively sharp correcting turns.No significant differences in orientation were observed between intact and unilaterally-antennectomized males, except that correcting turns close to the pheromone source were significantly less precise in males with one antenna. These results indicate that males with two antennae have an advantage over males with one antenna in being able to employ simultaneous information processing close to the pheromone source. Males with crossed antennae were unable to locate the pheromone source, suggesting that the fixed position of their antennae interfered with sensory information input.  相似文献   

18.
P Talwar  B Kumar  A Ayyagiri  S Kaur 《Sabouraudia》1985,23(4):303-312
Ninety-six patients with clinical evidence of interdigital lesions classified as mild, moderate and severe athlete's foot were investigated for bacterial and fungal populations in the interspaces. Gram-negative bacteria, which were not found in the toe spaces of 50 normal controls, were grown in increasing numbers and with increasing frequency as the symptoms progressed from mild to severe. Gram-positive bacteria were also isolated regularly and in increasing numbers commensurate with the severity of the disease. Similarly the isolation rates of dermatophytes and Candida species were higher in patients with moderate and severe disease compared to those with mild disease. Clinical and culture responses to topical applications with framycetin, tolnaftate, miconazole and clotrimazole were also studied. In some patients the prevalence of pathogenic fungi increased as bacterial numbers decreased. The pure antibacterial framycetin brought symptomatic relief, as did the purely anti-dermatophyte substance tolnaftate, but best results were seen with two azole compounds having mixed antibacterial and antifungal properties.  相似文献   

19.
Plaice ( Pleuronectesplatessa L.) from three spawning areas in the southern North Sea were examined for six species of metazoan parasite. Differences of both incidence and level of infestation with particular parasite species were found in fish from the three areas. Neither the incidence nor the level of infestation was associated with the length of fish in the samples except in the case of the larger male fish from Flamborough, which tended to contain more larval nematodes (Anisakidae). All fish contained the intestinal nematode Cucullanus heterochrous , although fewer were found in fish from Flamborough. Southern Bight fish were more likely to contain Capillaria wickinsi than were fish from Flamborough or the German Bight. Flamborough fish were more likely to contain Anisakidae larvae than were fish from the other two areas. Fish from the three areas were similarly infested with Zoogonoides viviparus. Male fish from Flamborough were less likely to be infested with Lepeophtheirus pectoralis than male fish from the German Bight.  相似文献   

20.
Intact and splenectomized sheep with and without a rumen fistula were used to investigate changes in the jugular blood haematocrit and plasma osmolality during hourly and once-daily feeding regimes. Osmolality was also estimated in the ruminal fluid of fistulated sheep with spleens. Haematocrit decreased in sheep with spleens before they were given a once-daily feed; it increased when these sheep started to feed, reaching a maximum increase of 13% after 30 min of feeding; it decreased during the remaining 45 min of feeding time and usually continued to decrease after feeding stopped. These changes were not due to diurnal influences. Splenectomized sheep fed once daily showed only small decreases in haematocrit before they were fed. Increases occurred with the onset of eating but they were smaller (7%) than in intact sheep and were of shorter duration. In hourly fed sheep with spleens, haematocrit decreased in the early stages of sampling in a manner similar to that for sheep fed once daily. The changes in haematocrit that did occur were not related in any obvious manner to the feeding regime. The haematocrit in splenectomized sheep fed hourly was stable throughout feeding. Variations in the haematocrit in splenectomized sheep, equivalent to a range of 13% in one of them, were observed in a series of blood samples obtained during a 5-h period remote from the feeding time. Large increases occurred in osmolality of ruminal fluid when sheep were fed daily and this was abolished by hourly feeding. Plasma osmolality in sheep fed once daily increased slowly. Maxima occurred after 100 min from the start of eating and were 7% greater than prefeeding values. Only minor changes were observed when these sheep were fed hourly.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号