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Effects of topical and systemic atropine [sulphate] on intraocular pressure and pupil diameter in dog's eye
2008
Kovalcuka, L., Latvia Univ. of Agriculture, Jelgava (Latvia) | Birgele, E., Latvia Univ. of Agriculture, Jelgava (Latvia)
The objective of this study was to determine the effects of topical 1% atropine sulphate and systemic atropine sulphate on intraocular pressure (IOP) and horizontal pupil diameter (HPD) in dog’s eyes. Ten adult dogs for each treatment were used in this study. Dogs of different age, breed and sex were examined clinically and ophthalmologicaly. All animals were clinically and ophthalmologically healthy. One drop of topical 1% atropine sulphate was used in ten dogs unilaterally, with the contralateral eye acting as a control. IOP and HPD were measured every 5 minutes. In ten dogs systemic atropine sulphate were used intramuscularly (IM) with IOP and HPD measured every 5 minutes. In both study phases IOP and HPD were measured over a total duration of 60 minutes. After unilateral application of topical atropine, IOP increased significantly in the treated eye. A maximum average IOP of 20.3 mmHg in the treated eye was observed 20 minutes after treatment. Maximal pupil dilatation in the treated eye was observed 35 min after treatment. Measurements made after systemic atropine showed an IOP increase in both eyes, showing maximum average IOP increase 25 minutes post-treatment. Maximum average values of HPD were obtained 25 minutes after treatment. The HPD started to decrease 30 minutes after treatment but it was still significantly higher than before treatment (P is less than 0.05). Because of atropine sulphate’s ability to cause significant increase in IOP, it should not be used for diagnosis and treatment of glaucomatous eyes.
显示更多 [+] 显示较少 [-]Lactic acid bacteria in rye sourdough from crude and peeled rye flour
2008
Kozlinskis, E., Latvia Univ. of Agriculture, Jelgava (Latvia) | Skudra, L., Latvia Univ. of Agriculture, Jelgava (Latvia) | Klava, D., Latvia Univ. of Agriculture, Jelgava (Latvia) | Kunkulberga, D., Latvia Univ. of Agriculture, Jelgava (Latvia)
In Latvia the spontaneous sourdough is used in traditional rye bread baking whose microflora is determined in flour and in microorganism cultures presented in external environment. Almost all spontaneous sourdough cultures, especially those that have been maintained for a long time, contain both lactic acid bacteria (LAB) and yeasts. The main purpose of the current research was to analyze growth dynamics of LAB in spontaneous rye flour sourdough and to isolate some of its representatives. Experiments were carried out in the Department of Food Technology of the Faculty of Food Technology of Latvia University of Agriculture in January and February 2008. Considering differences in constituents, two types of flour were used in the research - peeled and crude rye flour. There were three stages of spontaneous sourdough preparation in 72 hours totally; the renewal of sourdough was realized each 24 hours. The dynamics of LAB plate count in every stage of fermentation was investigated as well as changes of pH was observed using standard methods. The results of experiments show substantial increase in amount of LAB in both sourdoughs, particularly in sourdough from peeled flour, reaching 6.06 log10 cfu mlE-1. A significant decrease of pH value from pH 6.7 to pH 3.8 during fermentation process was observed. As a result, the sourdough from peeled flour had desirable properties for preparation of sourdough starter. LAB cultures isolated and identified from current sourdoughs using API tests: Lactobacillus brevis and Lactobacillus fermentum are also typical members of sourdoughs found in other countries.
显示更多 [+] 显示较少 [-]Nutritional changes in several potato varieties during heat treatment processes
2008
Murniece, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Karklina, D., Latvia Univ. of Agriculture, Jelgava (Latvia) | Galoburda, R., Latvia Univ. of Agriculture, Jelgava (Latvia)
Processing and cooking methods can greatly affect the nutritional value of fruits and vegetables including potatoes. In human nutrition potatoes before consumption are always prepared by several cooking methods and are one of the central components of warm meals. During treatment processes considerable changes in nutritional composition and nutritional quality of the product are induced. Hence the aim of the study was to determine the amount of basic nutrients (carbohydrate, fat and protein) as well as essential amino acids in five Latvian potato varieties prepared by the following heat treatment methods: baking in oven, shallow frying and deep fat frying and to compare the obtained results with recommended daily intake (RDI). Achieved results show significant differences in total carbohydrate amount within potato varieties (p=0.007) while within the type of heat treatments were no significance (p=0.065). Changes in fat content between heat treatment processes were considerable (p=0.000) whereas significance were discovered between control – pan fried, control – deep fat fried, baked in oven – pan fried, baked in oven – deep fat fried as well as pan fried – deep fat fried samples while no significance found among potato varieties (p=0.391). In protein amount neither within potato varieties nor between heat treatment processes significance was discovered, but the amount of essential amino acids significantly differs per each potato variety and type of heat treatment processes. Results on RDI per each nutrient group (fat, carbohydrates and protein) show significance on % RDI per each basic nutrient.
显示更多 [+] 显示较少 [-]Evaluation of texture parameters of vacuum and modified atmosphere packed fresh carp (Cyprinus carpio L.)
2008
Kamolina, E., Latvia Univ. of Agriculture, Jelgava (Latvia) | Dukalska, L., Latvia Univ. of Agriculture, Jelgava (Latvia)
Investigations of textural parameters of vacuum, protective gas atmosphere (MAP), and at air ambiance packed fresh carp (Cyprinus carpio L.) farmed in Latvia were carried out. The samples of carp were stored at two different temperatures (0 +- 0.5 and +4 +- 0.5 ºC) applying three different types of packaging – vacuum, MAP, and wrapping at air ambiance. Gas mixture used for MAP consisted of 40% CO2 and 60% N2. Samples were analyzed before packaging (day 0) and after 2, 4, 6, 8, 11 and 14 storage days. Textural parameters – hardness and shear force were evaluated by texture analyzer TA.XT.plus (Stable Micro System Ltd.). Two instrumental methods were applied for evaluation of textural properties. One method was based on compression test, using spherical probe, 25.4 mm in diameter (type P/1S), and measuring the hardness of the fillet and other method was based on cutting the fillet with a blade (type HDP/BSK) and measuring the shear force. The instrumental hardness and shear force of fresh carp fillets decreased during storage time. Texture variables significantly correlate with storage time, respectively, r = -0.723 and r = -0.748, the hardness and shear force. The storage time, temperature and packaging type with probability of 95 % substantially influence the textural parameters of carp fillets (P is less than 0.05).
显示更多 [+] 显示较少 [-]Investigation of polyploidy in the breeding of lilies (Lilium spp.)
2008
Balode, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
Some of best varieties of plants, especially ornamentals and fruits, were polyploid. Polyploids have larger flowers and stems than diploids. In the production of polyploid forms, different types of crosses were made. In present study a cross of diploid (2n = 2x = 24) and tetraploid (4n = 4x = 48) varieties resulted in the production of highly viable seeds 89.3% on average, but a cross of tetraploids and diploids – of 39.5% on average, with fluctuating results between cross combinations. Treating seeds and bulb scales with colchicine solutions can change chromosome number of 9 varieties. These results demonstrated that optimal concentration of colchicine was 1 g kgE-1 for chromosome doubling of seeds. A high concentration (2 g kgE-1) showed phytotoxicity that is detrimental for plant regeneration. The scales of bulbs treated with 1 g kgE-1 colchicine have resulted in the production of lily polyploid forms. The polyploid plants regenerated after pre-treatment by colchicine may be selected in early stage by phenotype of young bulblets. Broad, fleshy bulb scales setting right angle to growth axis were characteristic for regenerated tetraploids. The produced polyploid plants, in comparison with diploids, had a larger diameter of the flower (+2 up to 2.5 cm), more extended plant height (+10 up to 20 cm), increased flower count (+2) and was coming into bloom 4-10 days later than diploids of the same variety.
显示更多 [+] 显示较少 [-]The beef chain in Costa Rica: Identifying critical issues for promoting its modernization, efficiency and competitiveness
2008
Holmann, Federico J. | Rivas Ríos, Libardo | Pérez, E. | Castro, C. | Schuetz, P. | Rodríguez, J.
The objectives of this study were to (1) describe the economic agents of the chain and their commercial and legal relationships; (2) identify the articulations between links, technological levels, indicators of efficiency, installed capacity (scale), and degrees of occupation; (3) characterize and estimate the costing and pricing structures, and the generation of value in different links of the chain; (4) identify those critical costs that can be modified through technological interventions, policy, or other activity; (5) determine the biological and economic risk factors throughout the chain; and (6) develop a methodology to identify and estimate the costs and benefits in each segment and evaluate the generation of value throughout the beef chain. Data at the farm level was obtained from a national livestock survey (CORFOGA 2005b), which provided data on production systems, inventories, productivity, culling, and labor. In addition, surveys were carried out in different segments: (1) auction houses, (2) slaughterhouses, (3) butcher shops, and (4) supermarkets. The aim of these surveys was to describe behavior, determine risks and costs, and identify problems. The weak dynamics of livestock production in Costa Rica are reflected in unsatisfactory productivity indicators. The annual gross income was estimated as US$44/ha for cow-calf operations, $126/ha for dual purpose (including income from milk sales), and $135/ha for fattening activities. Such income rates are considered extremely low, if one uses as reference the commercial value of land allocated to livestock production (ranging between $1000 and $2000/ha). The aforementioned biological inefficiencies, combined with high land costs, impede the recovery of opportunity costs for the capital invested in land, thus making beef production uncompetitive. The cow-calf operation, with its low productivity, remunerates family labor with wages below the legal minimum. On the assumption that the only cash cost is that of labor, cow-calf farms pay family workers at a wage that is equivalent to 60% of the legal minimum. Auctions present relatively good profits per event. However, when these profits are analyzed on a calendar-day basis, they are unattractive because of the low use of installed capacity. One strategy that would usefully improve the efficiency of the auction system in Costa Rica is its integration to reduce the number of fixed operational costs or encourage sharing of these houses so that administrative and operational personnel are rotated among the several existing auctions, taking advantage of the fact that they differ in their days of operation. This scheme would help reduce fixed costs and the commission collected without affecting profits, thus improving efficiency in this link of the chain. However, this option is not easy to implement, as auctions are run by private operators, whose various interests do not always coincide. The industrial sector formed by rural and industrial slaughterhouses shows a low occupation of installed capacity, resulting in high operational costs and low labor efficiency. The total operational costs of slaughtering and dressing are estimated as being between US$32 and $66 per animal. If the estimated unit costs are compared with the rates charged per slaughtered animal (between $15 and $23), then we have to conclude that rural slaughterhouses work at a loss and that industrial slaughterhouses cover their operational costs with processing services and the very small profit margins from sales of byproducts. The best performance in terms of efficiency and profitability is found in the retail sector of butchers and supermarkets. The rate of profits, expressed as the fraction of the final price paid by the consumer that remains in the butcher’s hands as remuneration of his work, ranges widely between 3% and 40%, with an average of 32%. If these profit rates are compared with those of other retail businesses, which are about 8%, then this type of activity presents excellent profit margins with relatively low risk. If, in addition, we take into account that this sector also offers the consumer a broad range of meat cuts from other animals such as pork and chicken, and processed meats, then profit margins are still higher. The value generated throughout the chain, as a percentage of the final value of the young steer at retail price according to activity, is distributed as follows: fattener (34%), retailer (33%), breeder (19%), slaughterhouse (7%), transporter (6%), and auction house (1%). As observed, the distribution of value throughout the beef chain is totally inequitable and incongruent with the level of individual risk confronted by the actors who form it. The inequity observed in the distribution of added value reflects a clear dominant position in the market of some actors of the chain, which enables them to capture a very high fraction of the profits. The value generated in the chain, adjusted for operational time in each link, ranges between US$0.28/animal per day for the breeder and $45.85/animal per day for the butcher. Thus, the highest proportion of the total added value concentrates on the final link of the chain. The butcher or supermarket obtains, on the basis of one animal in the same unit of time, 164 times more value that the breeder located in the first link of the chain. The latter has to confront biological and economic risks not covered by insurance policies, whereas retailers may mitigate risks through insurance policies for their raw materials, equipment, and infrastructure. The competitiveness of the beef chain is the aggregate of the efficiency and productivity of all the links that form it. In a situation where, in the final segment, the demand for beef is low and weakly dynamic, then economic signs of modernization and the technological change it promotes, are not being generated in other components of the chain, particularly in the first link of production. This, in turn, results in a vicious cycle, generating low productivity and lack of competitiveness. To promote technological change, efficiency, and competitiveness in the value chain for beef in Costa Rica, we propose the following six recommendations: 1. That successful experiences of other chains such as that of poultry be analyzed and learned from to identify strategies that would increase the efficiency of the beef chain as a whole. 2. That strategies for promoting the milk production of breeding cows be developed to increase family income, as remuneration of labor is currently below the minimum wage. This option would be viable only in localities where a milk market exists. That livestock producer funds [a livestock producer fund consists of granting livestock in company to produce meat, provided that the producer concerned has adequate pastures for this purpose on his farm] be created as mechanisms to develop social capital, reduce transaction costs, and help improve the chain’s productivity and profitability. These organizations would bring together the different classes of the chain and favor synergies in the interaction of public and private actors. 3. That incentives be created to promote the large-scale adoption of already available improved forage species, as most of the problem of low livestock productivity originates in poor and deficient feed. This strategy would emphasize feeding during dry seasons, thereby minimizing seasonal weight losses in the national herd and improving the profitability of farms. 4. That a carcass classification system be established, based on quality and price that would permit differentiating supplies for different segments of the market. 5. That consumer education be promoted on the health benefits of beef, forms of preparation, and differentiating between cuts, uses, and qualities of beef products.
显示更多 [+] 显示较少 [-]Simulation of costs and benefits of supplementing milking cows with legumes during the dry season in two hillside regions of Nicaragua
2008
Holmann, Federico J. | Tiemann, Tassilo T.
Objectives of this study were to compare costs and expected benefits of feed supplementation in cattle with alternative shrub legumes during the dry season using as a case study the hillsides of Central Nicaragua. The information used was gathered in a survey of 32 farms in the states of Boaco and Chontales in Central Nicaragua. The survey was designed to determine herd structure, land use patterns, milk and beef production, and use of inputs for animal nutrition, in order to estimate production, reproductive parameters and employment of family/contracted labor, as well as indicators of profitability of the alternatives under study. To calculate the economic return to the investment in alternative forages, a simulation model that applies optimization techniques through linear programming, implemented as a spreadsheet, was used to perform an ex ante evaluation of the costs and benefits of different land use alternatives and of interactions between technological components and biological productivity. The model compares the costs and benefits of the traditional feeding system versus an improved feeding system. The traditional system consists of grazing naturalized pastures (Hyparrhenia rufa) during the rainy season. In the dry season producers supplement the herd with small areas of king grass (Pennisetum spp.). The improved feeding system consists of establishing forage legumes for dry season feeding as a supplement to replace king grass during the dry season. Supplements to evaluate are the shrub legume Calliandra calothyrsus as partial replacement of the herbaceous high quality legume Vigna unguiculata, commonly known as Cowpea. Under the new feeding system, herd size can be increased by 60% due in part to the increase in stocking rate as well as to the increase in the quality of the diet offered with higher protein content. This increase in herd size raises both milk and beef output that generates an increase in farm income by 1.8 times more (i.e., from $1,314/farm/yr to $2,386). The economic return to family labor is increased by 20% to $ 5.26/day equivalent to 2.3 times higher than the local wage rate. The adoption of Vigna (Cowpea) after the harvest of maize/beans and a shrub legume as Calliandra to replace king grass seem to have the potential to significantly improve the productivity in smallholder farms. with the resulting increase in the economic return to family labor.
显示更多 [+] 显示较少 [-]Wool characteristics of Libyan Barbary sheep in north-eastern Libya: I. Fiber diameter and staple length
2008
Akraim, F. | Milad, I.S. | Abdulkarim, A.A. | Ganem, M.
In this study wool characteristics of Libyan sheep in north-eastern Libya were investigated in a coastal region extended from El-Marj (32 25 N and 20 30 E) to Emsaad at the north-eastern border of the country (31 33N, 25 6 E). Twelve locations, one flock per flock were studied. Three sites have been sampled from each animal (Shoulder, mid-side and breech). Mean staple length and fiber diameter were 12.16cm and 38.43 µm respectively. In this study, staple length and fiber diameter didn’t significantly vary between locations studied. Sample site on the body of the animal significantly affect both staple length and fiber diameter, with breech position samples showed the shortest staple length and the thickest fiber diameter (P< 0.05). There was no difference between samples taken from mid-side or shoulder in all measured traits. Results of this study showed that Barbary sheep raised in the eastern part of the country characterized by a long staple and a large fiber diameter, and then confirmed the previous studies studies stated that this breed could be classed as a long carpet wool breed. Samples taken from mid-side position could be representative of Barbary sheep fleece
显示更多 [+] 显示较少 [-]Effect of live weight at slaughter on the carcass characteristics of intensively fattened Martinik sheep fed sugar cane supplemented with pea flour.
2008
Alexandre, Gisèle | Coppry, Ode | Bocage, Bruno | Fleury, Jérôme | Archimède, Harry | Unité de Recherches Zootechniques (URZ) ; Institut National de la Recherche Agronomique (INRA) | Plateforme Tropicale d'Expérimentation sur l'Animal (PTEA) ; Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)
International audience
显示更多 [+] 显示较少 [-]Comparaison des caractéristiques de production de la pintade locale (Meleagris numida) en station et dans le milieu villageois en zone soudano-guinéenne du Bénin | Comparison of local Guinea fowl (Meleagris numida) production characteristics in experimental station and rural area in soudano-guinean zone of Bénin
2008
Dahouda, Mahamadou | Sènou, Marcel | Toleba, Soumanou Seibou | Boko, Cyrille Kadoito | Adandédjan, Jean-Claude | Hornick, Jean-Luc
peer reviewed | A survey on the production characteristics of guinea fowl (Meleagris numida) was carried out in the Borgou department located in the soudano-guinean zone North-Est of Benin. Chicks and reproductive groups were kept either on station under improved management conditions or in rural environment. In rural environment, the birds were divided in two groups. The birds pertaining to the first group were treated against parasitic diseases, whereas those in the second one (control group) received no treatment. Under station conditions, the feed conversion ratio and the daily weight gain were 8.8 and 5.7 g/day respectively. Mean body weight at six months of age were 1151g and 1085g for males and females, respectively. Sexual maturity was reached at 36 weeks of age. For mature hens kept on station, laying rate and the mean egg weight were 37.2% (65% at the peak) and 41.1g respectively. Smothering, stress and pricking were the major constraints to the cloistering of guinea fowl. In rural environment, the mean hatchability rate was 70%. Mortality rate and adult body weight were not significantly different between groups. Mortality rate observed in the rural environment was 50% for both treated or untreated birds. Apart from the parasitic affections, the main causes of mortality were the rain, the predators, the cold and the fragility of chicks. The mean body weight at six months of age is higher for the birds raised under village conditions in comparison to the birds kept on station.
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