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Sallal E. Almutairi Ismaïl Boujenane Abdelgader Musaad Falah Awad-Acharari 《Tropical animal health and production》2010,42(6):1087-1092
Reproductive traits and calving weight were assessed in Saudi camels, and non-genetic factors influencing them were studied
using data collected at Al Jouf centre from 1987 to 2009. Age at first conception, age at first calving, open period, calving
interval, gestation length and weight at calving of camels averaged 42.3 months, 54.8 months, 10.6 months, 22.6 months, 377.5 days
and 591.9 kg, respectively. A mixed model including the camel as a random effect was used to assess the effect of environmental
effects on the traits studied. Age at first conception and age at first calving were affected by camel’s birth year. Open
period and calving interval were not affected by parity or year of calving. However, camels that calved from October to February
had a calving interval of 2.5 months higher than those that calved from March to September. Gestation length was affected
by season and year of calving but not by parity or sex of calf. Camels calving from March to September had a gestation length
6.6 days shorter than those calving from October to February. Weight at calving was affected by parity and year of calving
but not by season of calving. It was concluded that an improvement in camel reproductive traits is possible both through improving
management systems and utilisation of controlled breeding techniques. 相似文献
2.
Almutairi Sallal E. Boujenane Ismaïl Musaad Abdelgader Awad-Acharari Falah 《Tropical animal health and production》2010,42(8):1845-1853
The study was based on a set of 256 records for milk yield at 305 days, 1,899 records of test day yield, and 466 growth records
collected at Al Jouf center from 1987 to 2009. Except season of calving, milk yield at 305 days was affected by parity and
calving year, whereas test day yield was influenced by parity, calving year, stage of lactation, and test milk day. Only birth
year had a significant effect on all growth traits, whereas dam’s parity influenced weights at birth and 3 months, and birth
season affected birth weight, weight at 6 months and average daily gain (ADG) 3–6 months. Variance components estimated using
an animal model showed that heritability and repeatability estimates for milk yield at 305 days were 0.24 and 0.28, respectively.
The corresponding estimates for test day yield were 0.22 and 0.66, respectively. Direct heritabilities were 0.37, 0.50, 0.60,
and 0.85 for body weights at birth, 3, 6, and 12 months of age, respectively, and 0.25, 0.37, 0.49, and 0.29 for ADG 0–3,
3–6, 6–12, and 0–12 months, respectively. The annual genetic progress was 0.05 kg for milk yield at 305 days and 0.0003 kg
for test day yield. Annual genetic gains during 23 years were 0.050, −0.185, 0.079, and 0.331 kg for body weights, respectively,
and −9, −5, −4, and −13 g, for ADG, respectively. It was concluded that it is necessary to set up a field milk and growth
recording system in order to collect a large number of records to check these estimates. 相似文献
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Frida Kleitman Isaac Barash Annette Burger Naim Iraki Yunis Falah Guido Sessa Dan Weinthal Laura Chalupowicz Karl-Heinz Gartemann Rudolf Eichenlaub Shulamit Manulis-Sasson 《European journal of plant pathology / European Foundation for Plant Pathology》2008,121(4):463-475
Clavibacter michiganensis subsp. michiganensis (Cmm) strains, collected during the last decade from different locations in Israel, were analyzed by macrorestriction pulsed-field
gel electrophoresis (PFGE). Fifty-eight strains from Israel and 18 from other sources were differentiated into 11 haplotypes
with either VspI or DraI restriction enzymes. The strains from Israel formed four distinct groups among which groups A (16 strains) and B (32 strains)
constituted the major clusters. These two groups originated from the Besor region, which is the main area for growing tomatoes
under cover. Rep-PCR, with either ERIC or BOX primers, confirmed results obtained by PFGE. PCR with primers based on three
genes – ppaA, chpC and tomA – that spanned the pathogenicity island of the reference strain NCPPB382, produced the expected products with the tested
pathogenic strains. Plasmid analysis of representative strains revealed different profiles of one or two plasmids. However
all the strains, including five non-pathogenic ones, reacted positively in PCR with primers based on celA gene, which resides on the plasmid pCM1 of NCPPB382. Southern hybridization of total DNA with a 3.2-kb BglII-fragment of pCM1 containing the celA gene was positive when carried out with 31 strains, but the size of the reacting band was not always the same as that of
pCM1, suggesting that the plasmids carrying celA may differ in size. Comparison between the colonization rates of strain Cmm42 (group A) and of Cmm32 (group B) did not show any significant differences. The high diversity of the Cmm strains, on the one hand, and the presence of two persistent groups in the Besor region, on the other hand, suggests that
the primary inoculum originated each year from residual plants in the soil rather than from infested seeds, in spite of extensive
control measures taken by the growers in this area. 相似文献
4.
Gmelina arborea Roxb. is a fast-growing species and is known to have been used in traditional Indian medicine. Chemical constituents from
the bark have not been reported, although some chemical constituents from part of this plant (heartwood, leaf, and root) are
known. In this study, the bark meal was successively extracted with acetone and methanol. Fractionation of the acetone extract
with n-hexane, diethyl ether, and ethyl acetate and subsequent chromatographic separation of the fractions led to the isolation
of four compounds. The diethyl ether-soluble fraction yielded tyrosol [2-(4-hydroxyphenyl)ethanol] (1); (+)-balanophonin (2), an 8-5′ neolignan, with opposite optical rotation to known (−)-balanophonin; and gmelinol (3), a known lignan. The ethyl acetate-soluble fraction afforded a new phenylethanoid glycoside to the best of our knowledge,
which was identified as (−)-p-hydroxyphenylethyl[5′″-O-(3,4-dimethoxycinnamoyl)-β-d-apiofuranosyl(1′" → 6′)]-β-d-glucopyranoside (4). From the methanol extract, two known compounds, 2,6-dimethoxy-p-benzoquinone (5) and 3,4,5-trimethoxyphenol (6), were isolated and identified. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay of the identifi ed
compounds indicated that 3,4,5-trimethoxyphenol (6) exhibited moderate activity.
Part of this report was presented at the 57th and 58th Annual Meetings of the Japan Wood Research Society, Hiroshima and Tsukuba,
August 2007 and March 2008, respectively 相似文献
5.
Agricultural factors affecting methane oxidation in arable soil 总被引:9,自引:0,他引:9
CH4 oxidation activity in a sandy soil (Ardoyen) and agricultural practices affecting this oxidation were studied under laboratory conditions. CH4 oxidation in the soil proved to be a biological process. The instantaneous rate of CH4 consumption was in the order of 800 mol CH4 kg–1 day–1 (13 mg CH4 kg–1 day–1) provided the soil was treated with ca. 4.0 mmol CH4 kg–1 soil. Upon repeated supplies of a higher dose of CH4, the oxidation was accelerated to a rate of at least 198 mg CH4 kg–1 day–1. Addition of the plant-growth promoting rhizopseudomonad strains Pseudomonas aeruginosa 7NSK2 and Pseudomonas fluorescens ANP15 significantly decreased the CH4 oxidation by 20 to 30% during a 5-day incubation. However, with further incubation this suppression was no longer detectable. Growing maize plants prevented the suppression of CH4 oxidation. The numbers of methanotrophic bacteria and fungi increased significantly after the addition of CH4, but there were no significant shifts in the population of total bacteria and fluorescent pseudomonads. Drying and rewetting of soil for at least 1 day significantly reduced the activity of the indigenous methanotrophs. Upon rewetting, their activity was regained after a lag phase of about 3 days. The herbicide dichlorophenoxy acetic acid (2,4-D) had a strong negative effect on CH4 oxidation. The application of 5 ppm increased the time for CH4 removal; at concentrations above 25 ppm 2,4-D CH4–oxidizing activity was completely hampered. After 3 days of delay, only the treatments with below 25 ppm 2,4-D showed recovery of CH4–oxidizing activity. This finding suggests that it can be important to include a CH4–removal bioassay in ecotoxicology studies of the side effects of pesticides. Changes in the native soil pH also affected the CH4–oxidizing capacity. Permanent inhibition occurred when the soil pH was altered by 2 pH units, and partial inhibition by 1 pH unit change. A rather narrow pH range (5.9–7.7) appeared to allow CH4 oxidation. Soils pre-incubated with NH
4
+
had a lower CH4–removal capacity. Moreover, the nitrification inhibitor 2-chloro-6-trichloromethyl pyridine (nitrapyrin) strongly inhibited CH4 oxidation. Probably methanotrophs rather than nitrifying microorganisms are mainly responsible for CH4 removal in the soil studied. It appears that the causal methanotrophs are remarkably sensitive to soil environmental disturbances. 相似文献
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