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31.
The aim of this study was to evaluate the effects of ram introduction after the second prostaglandin F2α (PG F2α) injection on day 11 on the secretion characteristics of pre‐ovulatory LH surge of fat‐tailed ewes. Multiparous Morkaraman ewes (n=12) were divided into three groups by balancing the groups for liveweight (BW) and body condition score (BCS). On the day of second PGF2α injection (0 h), performance tested rams (n=2) were either introduced to the ewes at 0 h (ram 0 group, n=4) or at 18 h (ram 18 group, n=4) or were not introduced (control group, n=4). Blood samples were collected at 6, 18, 42, 48, 56, 62, 66, 70, 74, 78 and 90 h for the determination of pre‐ovulatory LH surge. BCS and BW during the experimental period were 2.2 ± 0.2 units and 50.9 ± 2.3 kg, 2.4 ± 0.4 units and 49.2 ± 6.2 kg, 2.1 ± 0.3 units and 45.9 ± 4.4 kg, respectively for the ram 0, ram 18 and control groups (p > 0.05). No significant difference was observed in LH surge characteristics for the experimental groups. Peak LH concentrations were also not different between groups (p > 0.05) and they were 12.2 ± 8.3, 29.1 ± 9.9 and 15.8 ± 9.5 μg/l for the ram 0, ram 18 and control groups, respectively. There was, however, a significant correlation between peak LH concentrations and BCS (p < 0.05, R2=0.373). In conclusion, it appears that, compared with ram introduction, variability in body condition of the ewe has much pronounced effect on the amount of LH secreted after the usage of two PGF2α injections (11 days apart) as a tool for oestrus synchronization.  相似文献   
32.
Phyllody is one of the most destructive diseases of sesame and causes serious yield losses worldwide. The present research was conducted to identify phyllody resistant genotypes in sesame. A total of 542 sesame genotypes were screened for the disease resistance in the field using a disease incidence scale of 1–5 in the year 2012. Three hundred four genotypes showing high disease intensity were eliminated under artificially infected field conditions. In the year 2013, only 30 out of 238 accessions were determined as potential resistant genotypes based on the disease incidence scale. These selected genotypes were further evaluated for confirmation of the resistance in greenhouse conditions using the phytoplasma-infected vector insects under choice and no-choice conditions. Furthermore, real-time qPCR was employed for detection and quantification of phytoplasmas to select true resistant genotypes. The sesame accessions ACS38 and ACS102 were identified as resistant to the disease after evaluation in field, greenhouse and qPCR assays. This work is one of the most comprehensive studies to select genotypes resistant to the diseases caused by phytoplasmas.  相似文献   
33.
High rates of unexplained mortalities (up to 70%) are anticipated in the cultured juvenile sea bass (Dicentrarchus labrax) in farms in the eastern Black Sea at least for the last 8 years. Diplectanum aequans, often blamed for the observed mortalities, is the only prevalent parasite impacting the health of sea bass in the brackish water of the Black Sea. To investigate the seasonal fluctuation of D. aequans prevalence, mean intensities and the potential effects of D. aequans on the fitness of sea bass, eight cages from one farm (Farm A) and four cages at another distinct site (Farm B) were surveyed monthly from May to October of 2008. Six hundred and sixty‐one juvenile sea bass from Farm A and 236 from Farm B were individually examined for the presence and intensity of the parasite. The prevalence of D. aequans in cultured sea bass (96.3 ± 11.11; Mean ± SD) ranged from 66.7% to 100% in June, the beginning of 6‐month growing season. The mean intensity was 6.08 ± 2.19, significantly higher than that (2.74 ± 0.87; P < 0.05) in December (P < 0.05), the end of the growing season. Fish with low fitness had significantly higher number of parasite than the fish with higher fitness (P < 0.005). Although D. aequans negatively influenced host's condition factor, the impact was not enough to lead mortalities in the cultured sea bass in the Black Sea.  相似文献   
34.
Sequence-related amplified polymorphism (SRAP), simple sequence repeats (SSR), inter-simple sequence repeat (ISSR), peroxidase gene polymorphism (POGP), resistant gene analog (RGA), randomly amplified polymorphic DNA (RAPD), and a morphological marker, Alternaria brown spot resistance gene of citrus named as Cabsr caused by (Alternaria alternata f. sp. Citri) were used to establish genetic linkage map of citrus using a population of 164 F1 individuals derived between ‘Clementine’ mandarin (Citrus reticulata Blanco ‘Clementine) and ‘Orlando’ tangelo’ (C. paradisi Macf. ‘Duncan’ × C. reticulata Blanco ‘Dancy’). A total of 609 markers, including 385 SRAP, 97 RAPD, 95 SSR, 18 ISSR, 12 POGP, and 2 RGA markers were used in linkage analysis. The ‘Clementine’ linkage map has 215 markers, comprising 144 testcross and 71 intercross markers placed in nine linkage groups. The ‘Clementine’ linkage map covered 858 cM with and average map distance of 3.5 cM between adjacent markers. The ‘Orlando’ linkage map has 189 markers, comprising 126 testcross and 61 intercross markers placed in nine linkage groups. The ‘Orlando’ linkage map covered 886 cM with an average map distance of 3.9 cM between adjacent markers. Segregation ratios for Cabsr were not significantly different from 1:1, suggesting that this trait is controlled by a single locus. This locus was placed in ‘Orlando’ linkage group 1. The new map has an improved distribution of markers along the linkage groups with fewer gaps. Combining different marker systems in linkage mapping studies may give better genome coverage due to their chromosomal target site differences, therefore fewer gaps in linkage groups.  相似文献   
35.
Wind erosion is a serious land degradation phenomenon in semi-arid parts of Turkey. It is even becoming more critical problem considering the current effects of global warming and climate change in the region. The objectives of this study are to model spatial variation of aeolian sediment transport and to map Sediment Transport Rate (STR) by geostatistics in a fallow plot in the Central Anatolia. STRs for four consecutive wind cases with different vegetation cover rates were determined using the cyclone BEST sediment traps. Plant cover ratio and height changed between 8 and 25% and 3–12?cm throughout the research period, respectively, and soil moistures ranged between 10.9 and 12.7%. The windstorms lasted for 400, 835, 1240, and 50 minutes with the mean wind velocities of 8.6, 7.7, 7.7, and 6.3?m?s?1, respectively, for cases 1, 2, 3, and 4. The calculated STRs varied between 0.0248?±?0.0170?kg?m?1?h?1 and 0.190?±?0.084?kg?m?1?h?1. Spatial analysis revealed that the spatial correlations were between 19 and 48?m and different spatial patterns occurred from one case to another. The study results indicated that the amount of transported sediment and its spatial variation were mostly related to velocity and duration of erosive wind in the fallow area of the arid region.  相似文献   
36.
The purpose of this study was to evaluate the sedative-anaesthetic effects of a combination of medetomidine (M, 50 microg per pigeon), butorphanol (B, 50 microg per pigeon) and ketamine (K, 25 mg per pigeon) in domestic pigeons. Eight domestic pigeons (four male and four female, 8-15 months old) were used. The combination of Medetomidine and butorphanol injectable solutions were used to produce sedation. Ten minutes after M + B administration, K was injected. The anaesthetic effects of the drugs were reversed by administration of Atipamazole (AT) at 60 min after K administration. All drugs were injected into the pectoral muscles. The sedative-anaesthetic effects of the M + B-K combination and, alterations in respiratory rate (RR), heart rate (HR), electrocardiographic (ECG) findings and cloacal temperature (CT) were investigated before and 10 min after pre-medication with M + B, at 5, 15, 30, 45 and 60 min during the onset of K anaesthesia and at 1, 5, 10, 20, 30 and 60 min following the administration of AT. The HR and RR of pigeons decreased within 10 min following M + B administration and remained lower until 1st and 5 min of AT injection, respectively. In ECG, no significant alterations in P, Q, R and S-values were observed, however, arhythmia was recorded for three pigeons, which returned to normal values following AT administration throughout the measurement. Cloacal temperature decreased gradually during the anaesthesia from 41.0 to 32.7 degrees C. The drug combination used in this study produced a satisfactory general anaesthesia for seven of the eight pigeons. All pigeons were unconscious within 5 min after K administration as indicated by disappearance of the palpebral and corneal reflexes and lack of reaction to the pain stimuli during the study. The effect of AT administration was observed within 10 min as all pigeons responded partly against stimuli and all reflexes. It is concluded that M + B-K anaesthesia in pigeons is a safe and reliable anaesthetic protocol for surgery.  相似文献   
37.
The aim of this study was to determine the level and duration of progesterone secretion during the sequential oestrous cycles in fat-tailed Tuj ewes following tactile and visual separation of rams during the breeding season. For these purposes, rams were separated from the main flock for 50 days starting from the beginning of the breeding season and 21 ewes were randomly selected for the current experiment. In order to assess luteal activity and the length of oestrous cycles, the ewes were blood-sampled thrice or twice weekly for the measurement of progesterone in plasma. The data showed that 3 +/- 0.2 oestrous cycles were observed in this time window, and the first oestrous cycle observed was shorter (P < 0.05) than the following cycles (mean +/- SEM, 14.6 +/- 0.82, 16.5 +/- 0.48 and 17.0 +/- 0.54 days, respectively, for cycles 1, 2 and 3). Progesterone production was significantly lower in the first oestrous cycle compared with the second and third cycles on days 9, 12 and 14 of the cycles. The follicular periods of ewes showed four accumulations (maximum values using a 3-day moving average technique) throughout the study and the percentages of ewes at each accumulation (peak day +/- 1 day) were 50, 35, 65 and 80% for the first, second, third and fourth accumulations, respectively (P < 0.05). It was concluded that progesterone production was lower and the oestrous cycles were shorter during the first oestrous cycle and that tactile and visual separation of rams at the beginning of the breeding season might enhance the synchronizing effect towards the end of the breeding season in the fat-tailed Tuj ewes.  相似文献   
38.
In this study, heart and respiratory rates, cloacal temperature, and quality of sedation were evaluated before (0 min) and after (10, 20, and 30 min) i.m. administration of xylazine (10 mg/kg; n = 7), medetomidine (75 li; n = 6), detcmidine (0.3 mg/kg; n = 6), or diazepam (6 mg/kg; n = 7) in rock partridges (Alectoris graeca). All partridges recovered from sedation without any disturbance. Xylazine and diazepam administration did not induce significant changes in heart rate, which did decrease significantly after medetomidine and detomidine administration (P < 0.001). Mean respiratory rate was decreased dramatically at 20 and 30 min after xylazine (P < 0.001) and medetomidine (P < 0.005) administration, and at all stages of sedation after detomidine injection (P < 0.001), whereas there was not any significant change after diazepam injection. In all groups, cloacal temperature measured at 10, 20, and 30 min tended to decrease compared with baseline values. Sedative effects of the drugs started within 2.1+/-0.2 min for detomidine, 2.6 +/- 0.4 min for diazepam, 3.1 -+/-.4 min for xylazine, and 4.8+/-0.8 min for medetomidine application. There was an extreme variability in time to recovery for each drug: 205 +/-22.2 min for xylazine, 95 -12.2 min for medetomidine, 260+/-17.6 min for detomidine, and 149 + 8.3 min for diazepam. In conclusion, xylazine, medetomidine, detomidine, and diazepam produced sedation, which could permit some clinical procedures such as handling and radiographic examination of partridges to occur. Of the four drugs, xylazine produced stronger and more efficient sedation compared to the others, which could permit only minor procedures to be performed. However, depending on the drug used, monitoring of heart and respiratory rates and cloacal temperature might be required.  相似文献   
39.
Mal secco (caused by Phoma tracheiphila (Petri) Kantsch. and Gik.) is the most destructive fungal disease of lemon plantations worldwide and seedless lemons would be preferred by most consumers. Five dosage levels, 0, 3, 5, 7, and 9 kiloradian (krad), of cobalt (60Co) gamma irradiation were applied to budstick of ‘Kutdiken’ lemon (Citrus limon (L.) Burm. f.) clone KT-2A. Mutations were stabilized in three vegetative generations. Three hundred fifty-eight and 478 M1V3 (mutation one and vegetation three) plants were evaluated for seed number and mal secco tolerance in the field and the greenhouse, respectively. LD50 was around 5 krad gamma irradiation for ‘Kutdiken’ lemon. The seed number varied from 0 to 34 per fruit. The level of mal secco tolerance also varied significantly among the plants from 1.0 (no symptom) to 4.3 (high level of disease occurance). The stable seedless and mal secco tolerant plants were obtained from 5 and 7 krad irradiation: the three mutants from 5 krad irradiation gave more lemon-like fruits, while 7 krad irradiation caused altered tree morphology and early maturation of fruits. This study shows considerable potential for lemon cultivar improvement aiming to obtain seedless and mal secco tolerant lemons.  相似文献   
40.
In order to increase knowledge of seed nutritive value and to demonstrate its relationship in common vetch (Vicia sativa L.) germplasm, 388 common vetch accessions were grown under field conditions in 2008–2009 growing season in Bursa province of Turkey. Seeds were analyzed for seed minerals (Ca, Cu, Mg, Mn, P, S, Zn and K) and crude protein (CP) content. The accessions were grouped according to testa and cotyledon color and seed size, and the results were evaluated by analysis of variance to determine relationships between minerals and CP content, testa and cotyledon colors, and seed weight. In general, there was no significant difference between testa colors or cotyledon colors in minerals and CP content. However, seed weight was closely associated with minerals and CP contents in this study. Analysis of variance and correlation analysis showed that seed weight was closely associated with some minerals and CP content. The small seeds had significantly higher Ca, Cu, Mg, Mn, S, Zn and CP contents than medium and large seeds.  相似文献   
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