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51.
Hanene Khemiri João Pimenta António Amorim Pascale Chevret Saïd Nouira Alexandra M Lopes 《African Zoology》2017,52(1):9-20
Three Meriones species inhabit Tunisia, namely M. shawi, M. libycus and M. crassus, but little genetic data exist on these gerbils. We collected Meriones from eight localities in Tunisia, and obtained mitochondrial (cytochrome b) and nuclear (IRBP) gene sequence data for 37 and 13 specimens, respectively, belonging to two species: M. shawi and M. libycus. We also optimised three microsatellite markers previously described in M. unguiculatus to obtain a finer analysis of their genetic diversity and geographic structure, given their wide distribution. Phylogenetic inferences of cyt b and IRBP data for these species, in the context of other gerbillin data, corroborate their taxonomic affinities reported by previous studies. High cyt b haplotype diversity was observed in both species (25 haplotypes in 29 and 27 sequences for M. shawi and M. libycus, respectively) with little geographical structure for M. shawi but three divergent groups in M. libycus. The average microsatellite diversity within each population was high (HO ≥ 0.6, HE ≥ 0.8) with M. libycus populations attaining the highest values. Population differentiation was moderate for several population pairs (Fst ≥ 0.1), the highest being between M. shawi populations. However, genetic distance among populations was not significantly correlated with geographic distance in either M. shawi or M. libycus. Our results contribute to a better characterisation of Tunisian Meriones species, suggesting high geographic structure in mtDNA of M. libycus populations within North Africa. 相似文献
52.
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
53.
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
54.
Bordiga M Travaglia F Meyrand M German JB Lebrilla CB Coïsson JD Arlorio M Barile D 《Journal of agricultural and food chemistry》2012,60(14):3700-3707
Over forty-five complex free oligosaccharides (of which several are novel) have been isolated and chemically characterized by gas chromatography and high resolution and high mass accuracy matrix-assisted laser desorption/ionization mass spectrometry (MALDI-FTICR MS) in red and white wines, Grignolino and Chardonnay, respectively. Oligosaccharides with a degree of polymerization between 3 and 14 were separated from simple monosaccharides and disaccharides by solid-phase extraction. The concentrations of free oligosaccharides were over 100 mg/L in both red and white wines. The free oligosaccharides-characterized for the first time in the present study-include hexose-oligosaccharides, xyloglucans, and arabinogalactans and may be the natural byproduct of the degradation of cell wall polysaccharides. The coupled gas chromatography and accurate mass spectrometry approach revealed an effective method to characterize and quantify complex functional oligosaccharides in both red and white wine. 相似文献
55.
Verloigne M Van Lippevelde W Maes L Brug J De Bourdeaudhuij I 《Public health nutrition》2012,15(8):1380-1395
56.
Muhammad Nadeem Alain Mollier Christian Morel Alain Vives Loïc Prud'homme Sylvain Pellerin 《植物养料与土壤学杂志》2012,175(6):805-809
Phosphorus (P) is the least mobile nutrient in the soil as compared to other macronutrients and therefore frequently limits crop growth. During germination and early growth, seed‐phytate hydrolysis and seed‐P remobilization is the major P source for developing seedlings. The objective of this paper was to investigate whether seed‐P hydrolysis and remobilization of nonphytate P are sufficient for seedling P nutrition during early growth stages of maize. A large part of initial maize endogenous seed P reserves are mainly in the form of phytate. Till 70 cumulated degree days after sowing, nearly all the phytate (98%) was hydrolyzed and caused an increase in nonphytate P in seeds. Phytate hydrolysis and remobilization of nonphytate P was the main source of P supply for the newly growing seedlings and was not a limiting step for seedling P nutrition during the first four weeks of early growth. 相似文献
57.
Objective: To evaluate the clinical outcome of minimally invasive plate osteosynthesis (MIPO) for nonarticular tibial fractures stabilized using bone plates with or without an intramedullary rod (IMR). Study Design: Prospective study. Animals: Dogs (n=28) and 8 cats. Methods: After closed reduction, fracture fixation was achieved using an epiperiosteal plate inserted percutaneously through epiphyseal small incisions. In some fractures, an IMR was inserted via medial parapatellar arthrotomy. Radiographs were recommended every 3 weeks until clinical union. Postoperative tibial length and alignment were compared with contralateral measurements (P<.05). Time to clinical union and complications were recorded. Results: An IMR was used in 30.5% of the cases. Repaired tibiae were 1% shorter than contralateral tibiae (P<.05). Frontal and sagittal alignment were similar between repaired and contralateral tibiae (P>.05). Six dogs were lost for follow‐up; owners indicated normal function. In 30 cases for which bone healing was documented, mean±SD healing time was 45±20.8 days; however, when considering the 23 cases, which completed preestablished scheduled follow‐ups, healing time was 36±11.6 days. Minor complications occurred in 4 cases (11%). One major complication (3%) consisting of a plate fracture was successfully revised using MIPO with a larger plate. Conclusions: Consistent restoration of alignment was accomplished using MIPO techniques. Furthermore, MIPO appeared to yield faster healing times and lower complication rates than those reported with conventional plate osteosynthesis. 相似文献
58.
Tropical Animal Health and Production - The aim of this article was to review the milk let-down in camels and to propose a simple milk recording method. Milking of camels generally starts between 1... 相似文献
59.
Barley (Hordeum vulgare L. cv. Martin) plants grown in solution culture, were exposed to increasing cadmium (Cd) concentration (0, 5, 10, 25, 50, and 100 μM) for a duration of 12 days. The sequence of important biochemical steps of nitrate (NO3) assimilation were studied in roots and shoots as a function of external Cd concentration. Cadmium uptake in roots and shoots increased gradually with Cd concentration in the medium. This Cd accumulation lowered substantially root and shoot biomass. The nitrate reductase (NR, EC 1.6.6.1) and nitrite reductase (NiR, EC 1.6.6.4) activities declined under Cd stress. Concurrently, tissue NO3 contents and xylem sap NO3 concentration were also decreased in Cd‐treated plants. These results suggest that Cd could exert an inhibitory effect on the assimilatory NO3 reducing system (NR and NiR) through a restriction of NO3 availability in the tissues. We therefore examined, in short‐term experiments (12 h), the impact of Cd on NO3 uptake and the two reductases in nitrogen (N)‐starved plants that were pretreated or not with Cd. It was found that Cd induced inhibition of both NO3 uptake and activities of NR and NiR, during NO3 induction period. The possible mechanisms of Cd action on NO3 uptake are proposed. Further, in Cd‐grown plants, the glutamine synthetase (GS, EC 6.3.1.2) showed a decreasing activity both in shoots and roots. However, increasing external Cd concentration resulted in a marked enhancement of glutamate dehydrogenase (NADH‐GDH, EC 1.4.1.2) activity, coupled with elevated levels of ammonium (NH4 in tissues. On the other hand, the total protein content in Cd‐treated plants declined with a progressive and substantial increase of protease activity in the tissues. These findings indicate that under Cd stress the usual pathway of NH4 assimilation (glutamine synthetase/glutamate synthase) can switch to an alternative one (glutamate dehydrogenase). The changes in all parameters investigated were concentration‐dependent and more marked in roots than shoots. The regulation of N absorption and assimilation by Cd in relation to growth and adaptation to stress conditions are discussed. 相似文献
60.