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1.
K Ashley S Wilson JR Young HP Chan S Vitou S Suon PA Windsor RD Bush 《Tropical animal health and production》2018,50(1):63-73
Forage technology has been successfully introduced into smallholder cattle systems in Cambodia as an alternative feed source to the traditional rice straw and native pastures, improving animal nutrition and reducing labour requirements of feeding cattle. Previous research has highlighted the positive impacts of forage technology including improved growth rates of cattle and household time savings. However, further research is required to understand the drivers, challenges and opportunities of forage technology for smallholder cattle households in Cambodia to facilitate widespread adoption and identify areas for further improvement. A survey of forage-growing households (n = 40) in July–September 2016 examined forage technology adoption experiences, including reasons for forage establishment, use of inputs and labour requirements of forage plot maintenance and use of forages (feeding, fattening, sale of grass or seedlings and silage). Time savings was reported as the main driver of forage adoption with household members spending approximately 1 h per day maintaining forages and feeding it to cattle. Water availability was reported as the main challenge to this activity. A small number of households also reported lack of labour, lack of fencing, competition from natural grasses, cost of irrigation and lack of experience as challenges to forage growing. Cattle fattening and sale of cut forage grass and seedlings was not found to be a widespread activity by interviewed households, with 25 and 10% of households reporting use of forages for these activities, respectively. Currently, opportunities exist for these households to better utilise forages through expansion of forage plots and cattle activities, although assistance is required to support these households in addressing current constraints, particularly availability of water, if the sustainability of this feed technology for smallholder cattle household is to be established in Cambodia. 相似文献
2.
M. Ćurković J. Ramljak S. Ivanković B. Mioč A. Ivanković V. Pavić M. Brka C. Veit‐Kensch I. Medugorac 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2016,133(1):71-80
The phylogenetic layout of the genotyped (30 microsatellite) 18 sheep breeds in this study demands and provides the opportunity to evaluate both neutral and adaptive components of genetic diversity in a naturally and artificially selected and subdivided sheep population. Seven Pramenka strains from Bosnia and Herzegovina and Croatia characterized by a very low intensity of artificial selection, preserved the highest neutral genetic variability. Eight central and north‐western European breeds under considerable artificial isolation and selection preserved the lowest genetic variability. Only combinations of various phylogenetic parameters offer a reasonable explanation for underlying evolutionary forces working in the investigated island and mainland sheep breeds under variable natural and artificial selection. More than 60% of total genetic, diversity was allocated to virtually unselected Pramenka strains, and an additional 25% to native moderately selected Graue Gehoernte Heidschnucke and intensively selected Ostfriesische Milchschafe. Some economically very important breeds and strains did not contribute to a pool with maximal genetic diversity, while they play an important role in the cultural heritage of respective countries. 相似文献
3.
Renberg WC Johnston SA Carrig CB Budsberg SC Ye K Veit HP 《American journal of veterinary research》2000,61(5):484-491
OBJECTIVE: To evaluate a method for experimental induction of osteoarthritis in the hip joints of dogs. ANIMALS: 12 mixed-breed dogs. PROCEDURE: A unilateral triple pelvic osteotomy was performed. In 6 dogs, the iliac osteotomy was repaired with 45 degrees of internal rotation, reducing coverage of the femoral head by the acetabulum. In the other 6 dogs, the fragments were repaired in anatomic alignment. Radiography, force plate evaluations, and subjective lameness evaluations were performed before and after surgery. Dogs were euthanatized 7 months after surgery, and samples of cartilage and joint capsule were examined histologically. RESULTS: Subjective lameness scores, radiographic appearance of the hip joints, and Norberg angles were not significantly different between groups; however, force plate evaluations did reveal significant differences in vertical ground reaction forces. Femoral head coverage was significantly decreased with rotation of the acetabulum. Mild inflammatory changes were discernible in the joint capsule and articular cartilage of some dogs in both groups. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that 45 degrees internal rotation of the acetabulum does not consistently induce biologically important osteoarthritic changes in the hip joints of dogs. 相似文献
4.
Márcia Regina Fagundes-Klen Márcia Teresinha Veit Carlos Eduardo Borba Rosangela Bergamasco Luiz Gustavo de Lima Vaz Edson Antonio da Silva 《Water, air, and soil pollution》2010,213(1-4):15-26
Copper biosorption onto chemically modified biomass of marine alga Sargassum filipendula was investigated in a batch reactor and a fixed bed column. Experiments were carried out in the batch reactor to obtain kinetic and equilibrium data and to assess the copper desorption efficiency of different eluent solutions. The pseudo-first-order, pseudo-second-order, and Langmuir kinetic models were used to correlate kinetic data. The experimental data fitted well to the pseudo first order and Langmuir kinetic models. Langmuir and Freundlich models were applied to describe the equilibrium data obtained at a fixed temperature of 30°C and at pH values of 3.0, 4.0, 5.0, and 6.0. The maximum capacities of copper biosorption onto the algal biomass were 1.43, 1.59, 2.40, and 2.36 mequiv./g at pH 3.0, 4.0, 5.0, and 6.0, respectively. The efficiencies of two eluent solutions (calcium chloride and hydrochloric acid) for copper removal from the biomass were evaluated at different concentrations (0.1, 0.2, 0.5, and 1.0 mol/L). The efficiencies of the calcium chloride solutions varied from 1% to 14%, while efficiencies varying from 95% to 99% were obtained when hydrochloric acid solutions were applied. Three adsorption/desorption cycles were carried out in a fixed bed column using 0.1 mol/L hydrochloric acid as eluent solution. The results showed that an increase in the number of cycles led to a reduction in the adsorption capacity of the alga. The desorbed copper fraction presented no significant variation, remaining around 63% in the three adsorption/desorption cycles. 相似文献
5.
6.
"Tubules-Within-a-Tubule" Hierarchical Order of Mesoporous Molecular Sieves in MCM-41 总被引:1,自引:0,他引:1
The recently discovered mesoporous aluminosilicate MCM-41 consists of hexagonal arrays of nanometer-sized cylindrical pores. It is shown that this material can be synthesized by cooperative condensation of silicate and cylindrical cationic micelles. Careful control of the surfactant-water content and the rate of condensation of silica at high alkalinity resulted in hollow tubules 0.3 to 3 micrometers in diameter. The wall of the tubules consisted of coaxial cylindrical pores, nanometers in size, that are characteristic of those of MCM-41. The formation of this higher order structure may take place through a liquid crystal phase transformation mechanism involving an anisotropic membrane-to-tubule phase change. The hierarchical organization of this "tubules-within-a-tubule" particle texture is similar to that of the frustules of marine diatoms. 相似文献
7.
Within this paper we summarize the results of the Thaumetopoea processionea monitoring at two observation sites and try to interpret population dynamics from 2006 to 2010 considering meteorological data. Furthermore, observations on the behaviour of neonates associated with oak budburst are presented and discussed. In 2007 large larval colonies occurred and population densities peaked. Massive defoliation and larval migration due to food shortage were observed regularly leading to reduced female moth fecundity. Unfavourable weather conditions probably abetted OPM population decline in spring 2008. Additionally oak budburst was delayed remarkably. More detailed observations on the hatching process and the behaviour of single colonies revealed increasing mortality after two and a half weeks of starvation. The 2009 results indicated another increase of population densities, but exceeded cool and humid weather conditions in May 2010 presumably prevented a new OPM outbreak. In accordance with previous studies egg parasitisation seems to play a minor role in OPM population dynamics. 相似文献
8.
S R Arthur E T Kornegay H R Thomas H P Veit D R Notter K E Webb J L Baker 《Journal of animal science》1983,57(5):1200-1214
The effect of early nutrition on subsequent bone development was studied using gilts that had previously been fed ad libitum or 75% ad libitum intake and 100 or 150% National Research Council-recommended daily Ca and P from weaning to 100 kg. During the three-parity reproductive study, sows were fed a 14% protein diet. Metacarpals and metatarsals were taken from sows culled due to lameness or failure to breed and from sows after completing three parities. Femur and humerus articular cartilage and turbinates were described at necropsy. Metacarpals and metatarsals were heavier and tended to have thicker walls when sows were previously fed ad libitum or fed 150% Ca and P. Energy intake produced the greater response. Metacarpal breaking strength was greatest for sows previously fed ad libitum. Metatarsals were not affected by energy intake. Stiffness, Young's modulus of elasticity (YME) and flexural modulus for metacarpals and metatarsals were not affected by energy intake. Previously fed Ca and P intakes did not affect any of the mechanical bone characteristics. Metacarpals were heavier, had a greater breaking strength, were more elastic and exhibited slightly less resistance to bending than the metatarsals. The ether extract, ash, Ca and P content and the Ca:P ratio of metacarpals and metatarsals were not affected by previously fed energy or Ca and P intakes. The ether extract content tended to decrease and the ash, Ca and P content tended to increase with age. Articular cartilage and turbinate scores were not influenced by previously fed energy or Ca and P intakes. The YME and flexural modulus were the only bone characteristics that were even poorly correlated (average r = .25) with soundness scores, suggesting that high values result in poorer soundness scores. Energy and Ca and P intakes during growth and development had only minimal effects on bone characteristics and no apparent effect on structural soundness and longevity of sows kept for three parities. 相似文献
9.
Chickens were infected with an avian adenovirus group II isolate previously obtained from chickens exhibiting splenomegaly in commercial broiler flocks. The isolate was inoculated orally in 6-week-old experimental chickens, which were euthanatized and necropsied 6 days postinoculation. The primary gross lesions found were splenomegaly and splenic mottling. Numerous tissues from 12 chickens were taken for histologic evaluation. Histologic lesions included splenic reticuloendothelial cell hyperplasia with intranuclear inclusions. Lymphocytic degeneration was seen in the lungs of most chickens examined. Lung hemorrhage and edema with endothelial disruption and congestion of pulmonary arterioles were found less frequently. The splenic lesions in the chickens were similar to those seen in turkeys naturally infected with hemorrhagic enteritis, and the lung lesions resembled those seen in pheasants naturally infected with marble spleen disease. 相似文献