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271.
The aim of this study was to determine and quantify the wood‐decay fungi found on logs of forest tree species (beech, oak, hornbeam, Scots pine and fir) stored in log depots located in six different provinces in the Western Black Sea Region of Turkey. Additionally, it was aimed to determine the natural durability of some important wood species against the most commonly detected wood‐decay fungi. Eighteen families, 31 genera and 45 species belonging to the division Basidiomycota were detected; Antrodia crassa was identified for the first time in Turkey. The abundance of Panus neostrigosus, Polyporus meridionalis, Trametes hirsuta, T. versicolor and Stereum hirsutumincreased significantly with the holding time of the logs (r = 0.99, 0.87, 0.53, 0.57 and 0.78, respectively, p < 0.05). The majority of the fungal species were detected on logs stored in depots for 4–6 years (66%). The percentage of fungal species found on the logs with a holding time of three years or less was 29%, whereas the percentage for those detected on logs stored for seven or more years was 31%. Among the wood species, the greatest number of fungal species (29) and highest amount of fungi (2,539) occurred on beech wood. Natural durability tests showed that T. versicolor caused the greatest loss of wood mass, with an average of 23%. Field studies and natural durability tests performed in the laboratory showed that beech wood lost the most mass among the timber species studied. 相似文献
272.
This work investigated the ability of the gregarious larval endoparasitoid Cotesia glomerata L. (Hymenoptera: Braconidae) to adjust the progeny sex ratio and clutch size with repeated oviposition experience and the
effect of a honey-based diet on the clutch size. In the field-collected clusters many clusters were female-biased but some
clusters (3.8%) produced only male wasps, suggesting that there is a low percentage of unmated females in the field. Superparasitism
was common in the field, and females were believed to increase progeny sex ratio when attacking previously parasitized hosts.
In the laboratory, the number of eggs laid in a day tended to decrease with increasing female age. For females that were offered
two hosts per day and for those offered three hosts per day, this value became nearly the same at 9 days after the start of
oviposition. Old females which attacked many hosts tended to lay fewer eggs in a day than young ones. However, the degree
of this tendency was not the same for all the parasitoid females of all three groups because sperm remained viable throughout
a female’s lifetime. The amount of sperm used in a single oviposition bout seemed fixed and was not dependent on the number
of eggs laid. Over the 2 days of the clutch size response experiment, the number of hosts a female attacked per day was not
affected by the presence or absence of honey. 相似文献
273.
The effect of different cole crops was studied on biological parameters of Pieris brassicae (L.) in the laboratory at 28 °C, 65% RH, and 12L:12D photoperiod. The results indicated that host plants significantly affected
the life history, i.e. survival of developmental stages, oviposition period, and sex ratio of P. brassicae. Comparative study on different host plant revealed that P. brassicae required a maximum of 40 days to complete generation on cabbage, cauliflower, and broccoli. The survivorship and expectation
of life declined gradually with the advancement of age; the life expectancy of newly deposited eggs was 23.96 days while it
was 8.12 days at the time of adult emergence on cabbage. However, the fluctuations of mortality parameter were seen on all
the cole crops. On cabbage, 100% hatching of eggs with low larval mortality were noticed. The highest net reproductive rate
(R0) occurred on cauliflower, i.e. 27.1 followed by cabbage 24.89, females per female per generation. Intrinsic rate of increase
(rm), was found to be highest (0.09558954) on cauliflower followed by broccoli and cabbage, 0.078886 and 0.077551 females per
female per day, respectively. The smallest rm (0.059469 females per female per day) occurred on radish which shows that P. brassicae did not perform well on radish. In addition, P. brassicae may double in 7.2 days on cauliflower, 8.7 days on broccoli, and 8.9 days on cabbage. The sex ratio was computed as 1.5:1,
female:male, respectively on cabbage. 相似文献
274.
The primary structures of myoglobin (Mb) from the following five carangid species were determined: yellowtail Seriola quinqueradiata, greater amberjack Seriola dumerili, yellowtail kingfish Seriola lalandi, Japanese horse mackerel Trachurus japonicus, and silver trevally Pseudocaranx dentex. The sequences were of varying composition both in the coding and in the noncoding regions, but all contained the open reading frame of 444 nucleotides encoding 147 amino acids. Amino acid sequence identities of carangid Mbs were in the range of 81-99%. The similarity of the heme pocket and associated heme-binding residues of carangid Mbs were evidence of the conservative nature of Mbs. Similar to the other teleost Mbs, carangid Mbs did not contain a D helix and had mostly conserved A and E helices as well as E-F and G-H inter-helical segments. Hydropathy profiles of carangid Mbs showed species-specific variations where silver trevally Mb exhibited generally higher hydrophobicity. Phylogenetic analysis based on the primary structures was in agreement with conventional morphological taxonomy, establishing close proximity of carangid Mbs with those of cichlid and scombroid, the other members of the Perciformes order. 相似文献
275.
The Optium Xceed is a new hand-held meter for determining blood β-hydroxybutyrate (BHBA) and glucose in human medicine. The objective of this study was to compare BHBA and glucose results obtained using the hand-held meter with those results made with a laboratory method and to evaluate its usefulness as a cowside test in the diagnosis of subclinical ketosis (SCK) in dairy cows. Seventy-eight blood samples from clinically healthy Holstein cows between 5 and 60 days post-calving were analysed. BHBA and glucose values were significantly higher with the hand-held meter versus laboratory methods. Correlation coefficients (r) for BHBA and glucose with the Optium Xceed versus laboratory methods were 0.97 and 0.63, respectively. Based on Bland–Altman plot and Passing–Bablok regression, agreement between two methods was good for BHBA but the agreement for glucose was only fair. When SCK was defined as plasma BHBA levels 1200 μmol/L, the sensitivity and specificity of the hand-held meter ketone testing in determining SCK were 85% and 94%, respectively. Raising the threshold of the laboratory method to 1400 μmol/L, the sensitivity and specificity incremented to 0.90 and 0.98, respectively.In conclusion, the blood ketone-monitoring device can be used as a rapid and reliable diagnostic test to detect SCK under field conditions. 相似文献
276.
Reproductive performance of Holstein dairy cows in Iran 总被引:2,自引:2,他引:0
Maryam Ansari-Lari Mojtaba Kafi Mohammad Sokhtanlo Hasan Nategh Ahmadi 《Tropical animal health and production》2010,42(6):1277-1283
The objectives of the present study were to describe the current reproductive parameters of Holstein dairy cows in Iran and
to determine factors which have a significant effect on reproductive performance with emphasis on high-producing dairy cows.
Five large Holstein dairy herds from the major milk production areas of Iran were selected for this study. Reproduction data
including parity of dam, calving date, days to first service, days open, number of services, dry period, and occurrence of
diseases for cows that calved from 2004 to 2007 were collected from the herds' databases. To determine the effects of year
and season of calving, disease status, level of milk production, and parity of dam on reproductive parameters, the proc-mixed
procedure in SAS software was used. Overall, data about 8,204 lactation were collected for the study. Results showed that
mean (±SD) days open, calving interval, and days to first service for study herds were 134 (±89), 403 (±86), and 67 (±38)
days, respectively. Conception rates at the first service and the overall service-conception rate were 41.6% and 41%, respectively.
The level of milk production and diseases had significant negative effects on days open and service per conception (P < 0.05); statistical analysis showed that for every 100-kg increase in milk yield, days open will increase by about 0.3 days.
However, no significant effect of level of productivity was observed on days to first service. The results of this study indicate
that high milk production is a risk factor for decreasing fertility in Iran, like many other parts of the world. 相似文献
277.
Onur Atakisi Hasan Oral Oguz Merhan Ayla Ozcan Bulent Polat Semra Kaya 《Research in veterinary science》2010,89(1):10-13
The aim of this study was to investigate total antioxidant (TAC), and oxidant capacity (TOC) and nitric oxide (NO) levels in milk of cows with subclinical mastitis. Brown Swiss and Holstein breed cows were screened with California Mastitis Test (CMT) to determine mammary glands with subclinical mastitis. Moreover, somatic cell counts (SCC) were determined electronically in all milk samples. Mammary quarters were classified as healthy (n = 25) or subclinical mastitis (n = 35) based on CMT scores and somatic cell count (SCC: ?200,000/ml or >200,000/ml) in milk. Nitric oxide, TOC and SCC levels were significantly higher (p < 0.001, p < 0.005 and p < 0.001, respectively) in milk from mammary quarters with subclinical mastitis compared to those from healthy mammary quarters. In conclusion, subclinical mastitis results in higher NO concentrations, TOC and SCC, and NO and TOC were positively correlated with SCC. Moreover, alterations in NO levels and TOC in milk could be used as an alternative diagnostic tool to screen for subclinical mastitis. 相似文献
278.
J A Hasan I T Knight C R Tate E T Mallinson R G Miller R R Colwell S W Joseph 《Avian diseases》1991,35(2):397-402
A total of 48 environmental drag-swab samples from various poultry farms were tested for the presence of Salmonella spp. by culture, an enzyme-linked immunosorbent assay-based Salmonella antigen screening (SAS) assay, and two DNA probes (radiolabeled and colorimetric). The radiolabeled DNA probe was allowed to hybridize with culture-positive samples (n = 8) and was found to detect Salmonella spp. in all cases (100%). Both of the probes, subsequently hybridized with culture-negative samples (n = 8), were observed to yield good agreement (91%) with the culture findings. The remaining samples (n = 32) were tested by the SAS assay, and where there was no agreement between the culture and SAS, samples were further examined by the DNA probes. Results using both probes agreed with those obtained by culturing the samples but did not agree with the SAS assay result when the ratio of samples tested to samples positive (S/P) cutoff value used was 0.5. 相似文献
279.
Lekcharoensuk C Osborne CA Lulich JP Albasan H Ulrich LK Koehler LA Carpenter KA Swanson LL Pederson LA 《Journal of the American Animal Hospital Association》2005,41(1):39-46
Medical records from cats diagnosed with uroliths at nine United States veterinary teaching hospitals from 1980 to 1999, and records of cats with uroliths submitted for analyses to the Minnesota Urolith Center from 1981 to 2000, were evaluated. A 10-fold increase in frequency of upper tract uroliths occurred in cats during the 20-year interval at the nine veterinary teaching hospitals. Calcium oxalate emerged as the predominant mineral type in upper tract uroliths, having increased more than 50-fold during the study period. These results emphasize the need for increased awareness of the occurrence of upper urinary tract uroliths in cats. 相似文献
280.
The efficacy of administering doramectin after moxidectin treatment, which has previously proved only partially effective, was evaluated in five Angora rabbits naturally infested with Sarcoptes scabiei mange. Evaluations included physical examination for clinical signs of sarcoptic mange and collection of skin scrapings for determination of mites. The rabbits first received two subcutaneous injections, 10 days apart, of moxidectin 1% injectable solution at a dosage of 0.2 mg kg(-1) of bodyweight. Although moxidectin treatment resulted in clinical improvement within 10 days post initial injection, on days 10 and 35 post initial treatment live mites were present in skin scrapings. Administration of doramectin 1% injectable solution using the same route and dosage and at similar intervals to moxidectin led to complete disappearance of signs of scabies and parasitological cure in all rabbits. 相似文献