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Influence of intercrop on plant growth and yield
2014
Dane, S., Latvia Univ. of Agriculture, Jelgava (Latvia);Pure Horticultural Research Centre, Pure parish, Tukuma municipality (Latvia) | Laugale, V, Pure Horticultural Research Centre, Pure parish, Tukuma municipality (Latvia)
The demand for healthy and reasonably cheap food is growing and governments are expanding policies to preserve soil fertility and nature. In addition, climatic conditions are changing. Arable lands are decreasing. Due to all of these changes food growers are looking for new growing technologies. A monographic method to tackle these problems has been used in this article. Intercropping is one of growing systems how to reduce negative climatic aspects and meet other demands. Intercrop is convenient for growers who grow plants in rows, and a companion plant can be sown or planted between rows. In this case farmers can get two yields from one plot. Thus, growers do not need two plots for growing different plants. The intercrop diminishes spreading of pests and diseases, suppresses weed growth, and reduces need for pesticides. Legume (Leguminosae) intercrop gives extra nitrogen to companion plants. Those are aspects that we know intercrop can give, but we do not know how significant the influence is, what kind of influence on nature intercrops give in long term, what kind of influence they have on incomes, yield and its quality. This article shows that there are many intercropping systems to reduce some negative aspects and increase beneficial ones. Intercropping can reduce some pests and diseases, but promote other problems. Intercropping suppresses weeds. For some systems it gives bigger yield, for some smaller, but in total it gives bigger protein yield. There are still many unanswered questions and completely unexplained points.
显示更多 [+] 显示较少 [-]Lodging cause height at the centre of gravity changes during vegetation period for oat
2014
Brunava, L., Latvia Univ. of Agriculture, Jelgava (Latvia);State Stende Cereals Breeding Inst., „Dižzemes”, Dižstende, Lībagi parish, Talsi municipality (Latvia) | Alsina, I., Latvia Univ. of Agriculture, Jelgava (Latvia)
Height at the centre of gravity is a part of mathematical model to interpret risk of lodging used for cereal crops. Because of the anatomical changes during vegetation period, several measured parameters in early milk stage (stem and panicle weight) will differ from over-ripe stage results in their values. The aim of this study was to define approximate values of calculated parameters describing oat (Avena sativa L.) height at the centre of gravity in early milk and over-ripe stages as well as determine connection with lodging risk. The trial was carried out at the State Stende Cereals Breeding Institute in 2013. There were 5 oat cultivars studied. At the investigated growing stages plant samples were taken from a field and in laboratory conditions stem/panicle weight and length measured. The height at the centre of gravity and gravity ratio were calculated using mathematical model by Berry (1998). Results showed that the value of the height at the centre of gravity in over-ripe stage was significantly higher (p is less than 0.01) than in early milk stage, but correlation with risk of lodging remained. Such lodging resistance describing mathematical model can be useful for oat as well as wheat cultivars.
显示更多 [+] 显示较少 [-]Potato minitubers technology – its development and diversity: a review
2014
Dimante, I., Latvia Univ. of Agriculture, Jelgava (Latvia);State Priekuli Plant Breeding Inst., Priekuli, Priekuli parish, Priekuli municipality (Latvia) | Gaile, Z., Latvia Univ. of Agriculture, Jelgava (Latvia)
The study consists of literature review on potato (Solanum tuberosum L.) initial seed material – minitubers production. This paper covers aspects of healthy potato microplants production techniques and subsequent greenhouse minitubers production methods. The diversity of conventional minituber growing techniques (on solid medium in greenhouses) is discussed. Review showed that obtained minitubers number depends on growing methods and variety. Physical manipulation during in vitro phase could have positive effects on minitubers yielding capacities.
显示更多 [+] 显示较少 [-]Fertilization value of early red clover, Washington lup and Crimson clover as green manure crops
2014
Bender, A., Estonian Crop Research Inst., Jogeva, Jogeva vad. (Estonia) | Tamm, S., Estonian Crop Research Inst., Jogeva, Jogeva vad. (Estonia)
Field trials were carried out at Jõgeva Plant Breeding Institute in 2008 – 2011 to identify the possibilities of using early red clover (Trifolium pratense L.) ‘Jõgeva 433’ (diploid), Washington lupine (Lupinus polyphyllus Lind.) ‘Lupi’ and crimson clover (Trifolium incarnatum L.) as green manure. Fresh material of the above species was ploughed into the soil in autumn of the sowing year. Fertilizer value was quantified through yield and grain quality of spring wheat ‘Vinjett’ and barley ‘Inari’. The composition and amount of ploughed biomass were recorded. By the time of ploughing, Washington lupine had produced the most abundant biomass. >From studied species crimson clover had the lowest fertilizer value – only by 6–7% extra yield of spring wheat in the following year. Crimson clover had no residual effect of fertilization in the second year. The fertilizer values of red clover and Washington lupine were approximately equal. Their effect on yield increase of spring wheat and barley lasted for three years, on grain quality for two years. Red clover, ploughed into the soil in the year of sowing, resulted in maximum spring wheat yield increase of 23.9%, compared with N 0 treatments; that of Washington lupine was 21.3%. The residual positive effect in the second year quantified as barley production increased by 6.2% in Washington lupine and 7.9% in red clover. The yield increase in the third year was 3.9% and 12.1%, respectively. Green manure increased the contents of crude protein and gluten in spring wheat and crude protein content in barley.
显示更多 [+] 显示较少 [-]Relationship between body condition score, milk productivity and live weight of dairy cows
2014
Petrovska, S., Latvia Univ. of Agriculture, Jelgava (Latvia) | Jonkus, D., Latvia Univ. of Agriculture, Jelgava (Latvia)
Live weight and body condition are indicators for dairy cow’s (Bos taurus) health, milk productivity and reproduction. Live weight and body condition are defined by genetic and non-genetic factors. These factors are dependent on dairy cows growing and welfare. The aim of research was to analyze body condition relationship with milk productivity and live weight. Data were collected from 49 different breed and lactation dairy cows. Research location was Latvia University of Agriculture Research and Study farm ‘Vecauce’. Data were collected from October 2013 to January 2014. Body condition score of all cows decreased from 2.8 ± 0.05 to 2.5 ± 0.04 points in research period. Milk yield increased from 35.6 ± 0.79 kg in the 1st recording to 40.9 ± 1.12 kg in the 2nd recording. Milk yield decreased in the 3rd recording (p is less than 0.05). Fat content was the lowest in the 2nd recording (35.5 ± 0.09 g kgE-1). Protein content was significantly different in the 1st and 2nd recordings (p is less than 0.05). Somatic cell changes were not significant. Body condition decreased of older lactation cows, but milk yield increased at the same time. Milk yield was significantly the greatest in red breed group, compared with Holstein black and white cows (51.1 ± 3.21 kg vs. 41.4 ± 0.78 kg; p is less than 0.05). Body condition score significantly affected live weight in such body condition score groups: less than 2.5 points, 2.75 to 3.0 points. Effect was not significant on live weight in body condition score 3.25 less than group. Milk productivity and quality traits were not affected by the body condition score (p is less than 0.05).
显示更多 [+] 显示较少 [-]Dairy cow behaviour at individual feeding bins, can we estimate intakes from behavioural observations?
2014
Soonberg, M., Estonian Univ. of Life Sciences, Tartu (Estonia) | Arney, D.R., Estonian Univ. of Life Sciences, Tartu (Estonia)
Estimating feed intakes of individual cows in a loose-housed system is difficult and unreliable. It is known that estimating intakes from the number of bites taken at grazing is unreliable. Feeding from a total mixed ration (TMR) is likely to have fewer confounding variables. All cows were over 30 months old, of three breeds: Holstein Friesian, Estonian Red and Estonian Native. There were 30 feeding bins and 66 cows. Cows were observed over the whole 24 hour period, from 1st July to October 22nd 2011, in Märja experimental farm, of the Estonian University of Life Sciences, and data from 37 cows were collected. Measures taken included: time spent at the feed bin, number of bites taken at each visit, weight lost from the bin, and evidence of stealing. Mean time spent at each visit to the feed bin with standard error was 4.4 + 0.68 minutes. The mean number of bites per visit was 7.1 + 1.01. There was a significant correlation between the number of bites and total time cows spent feeding (p is less than 0.001), with a regression R2 value of 79.8%. No correlation was found between the number of bites and feed removed at each visit (p=0.851) nor between the time per visit and amount of feed removed (p=0.681). Therefore, there is no evidence that either the number of bites taken per visit or the time spent at bin per visit is related to intakes. There was no effect of age. Stealing was evident and widespread.
显示更多 [+] 显示较少 [-]Consumer attitudes towards the introduction of ready-to-eat meals in the Latvian market
2014
Ruzaike, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Muizniece-Brasava, S., Latvia Univ. of Agriculture, Jelgava (Latvia) | Janmere, K., Latvia Univ. of Agriculture, Jelgava (Latvia)
Nowadays the demand for fast and easy-to-make meals is ever increasing. This type of food is an essential dietary component of a large section of people in developed countries. Given the economic importance of ready-to-eat meals there is a need for a better understanding of the factors that determine their consumption. The aim of this research was to determine consumer attitudes towards the introduction of ready-to-eat meal (MRE) sets in the Latvian market. A survey was performed to determine the Latvian citizens’ attitudes towards the introduction of this type of quick-tomake, ready-to-eat products into the market of Latvia. The survey included a total of 800 respondents who answered 14 questions which were related to the interest in MRE sets that can be prepared (warmed up etc.) in less than 10 minutes and taste like home-cooked food, and the types of MRE sets these consumers would like to purchase. The demand forecast for MRE sets in the Latvian market is rather high as 67% of the respondents expressed a desire to purchase these products; the development and implementation of MRE sets is topical. The results show that the highest rated MRE set the respondents, a total of 77.1%, expressed a desire to purchase, was chicken fillet with vegetables. No significant differences in terms of liking were observed between chicken fillet with vegetables and chicken fillet with rice, the second highest rated MRE set by 73.9% of the respondents (p is greater than 0.05).
显示更多 [+] 显示较少 [-]Investigation of total protein content and amino acid composition of whole grain flour blend for pasta production
2014
Kalnina, S., Latvia Univ. of Agriculture, Jelgava (Latvia) | Rakcejeva, T., Latvia Univ. of Agriculture, Jelgava (Latvia)
The purpose of the current research was to investigate the total protein content and amino acid composition of flour blend made from several types of whole grain flour for pasta production. Conventional rye, hull-less barley, triticale and wheat grain was used in the experiments. For the flour blend obtaining white wheat flour type 550 was used. Using standard methods the following quality parameters were analysed: protein content in grain and flour samples by using InfratecTM model 1241 Grain Analyzer, in flour blend – by AACC 46–20, amino acid content by LVS ISO 13903:2005. In the present research it was determined that it is possible to increase the total protein content in wheat flour type 550 by 11% if adding whole wheat or whole triticale flour, and by 7% if adding whole grain flour of hull-less barley. Higher total amino acid content was obtained for whole wheat flour sample; lower – for whole rye flour sample. Significantly lower total amino acid content was obtained in whole rye, hull-less barley and triticale flour comparing with whole grain wheat flour. No significant differences (p=0.779) were found in the analysed essential amino acid content made of different flour blend – the content of essential amino acids in the analysed flour blend samples was very similar.
显示更多 [+] 显示较少 [-]Staphylococcus species in different age groups of pigs in Latvia
2014
Ivbule, M., Latvia Univ. of Agriculture, Jelgava (Latvia) | Valdovska, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
Antibiotic resistance of Staphylococcus is increasing worldwide. New antibiotics are used in big amounts in the meat production more and more. As a zoonosis, Staphylococcus aureus (S. aureus) is found in various species of animals and people, especially in those, who are working on commercial swine farms and slaughterhouses. The aim of the study was to find out the occurrence of S. aureus in different age groups of pigs on commercial swine farms in Latvia. Microbiological samples (n=702) including nasal, rectal, milk and air samples were collected during October 2013 from three closed farms of different sizes and several age groups of pigs and investigated with microbiological standard methods. S. aureus was found in all swine farms. The occurrence of S. aureus in Latvian pig farms was 41% and the highest occurrence of S. aureus was among 3-3.5 month old piglets. S. aureus was 1.8 times more frequently found in nasal than in rectal samples, and only in 28.38% of pigs S. aureus was in both - nasal and rectal samples. S. aureus was found also in sow milk in 13% of samples and in 3 samples of air (n=23).
显示更多 [+] 显示较少 [-]Goat kids stomach morphological development depending on the milk type
2014
Otzule, L., Latvia Univ. of Agriculture, Jelgava (Latvia) | Ilgaza, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
In goats (Capra) the growth and functional development of certain parts of the multi-chambered stomach continue during the first few months after birth. The aim of this research was to clarify morphofunctional changes in the kids abomasa and rumina and live weight gain during the first 8 weeks of life. Research was performed in two parts. In the first part (P1) we used Saanen breed kids which were all kept in the same conditions and in the second part (P2) we used Saanen breed kids which were separated in two groups with different feeding diets. In P1 the stomach contents of the goat kids were collected after slaughter (on day 1, 17, 25 and 30), weighed full and empty. The gastrohromoscopical method proved that in the newborn kids the area where the abomasal pH is 3.0 and lower is about 10% of the surface of the abomasum, but in age of three weeks it is composing 80% of the mucosal surface of the abomasum. In P2 were two groups – in the first group (MMG) kids which were fed with dairy (mother) milk and lived with mothers, the second group (MRG) kids were fed with milk replacer and lived separate from mothers. The stomach contents were collected after slaughter(at day 45 and 60).We confirm that the most important age of stomach development and kids growth in postnatal period are the first 45 days. During this period the most significant differences can be observed. On day 60 there are no significant differences (p is greater than 0.05) between MMG and MRG stomach development.
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