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1162 Uppsatser om Litter size - Sida 1 av 78

Fortplantning och fortplantningsproblem hos tikar av svensk och finsk lapphund : en jämförande studie

The Swedish Lapphund is one of our eleven Swedish domestic breeds of dogs and one of Sweden?s oldest dogbreeds. The Finnish Lapphund?s origin and physical conformation is similar to that of the Swedish Lapphund. One aim of this study was to examine whether the average Litter size differs between these two closely related breeds, and if so, try to find causes for this.

Variation i fruktsamhet hos semingaltar

Artificial insemination (AI) has had a great influence on the development of pig production and is today widely practiced (Gerrit et al., 2005). With AI, genetic progress can at a short period of time be spread worldwide compared with using natural service and the best boars can be intensively used. This is also one of the biggest risks with AI; the impact of semen containing a genetic disease or contamination of pathogens can be enormous. Fortunately, it is a small risk of disease transmission due to many tests of the boars and the semen before use (Maes et al, 2008). It is important that the boars used for insemination have good breeding values along with good reproduction features and have good fertility results (Robinson et al., 2005).

Reproduktion och reproduktionsproblem hos taxtikar

Artificial insemination (AI) has had a great influence on the development of pig production and is today widely practiced (Gerrit et al., 2005). With AI, genetic progress can at a short period of time be spread worldwide compared with using natural service and the best boars can be intensively used. This is also one of the biggest risks with AI; the impact of semen containing a genetic disease or contamination of pathogens can be enormous. Fortunately, it is a small risk of disease transmission due to many tests of the boars and the semen before use (Maes et al, 2008). It is important that the boars used for insemination have good breeding values along with good reproduction features and have good fertility results (Robinson et al., 2005).

Genetisk studie av inavel och fertilitet hos hund :

Inbreeding, the mating of related individuals, has been the one dominating breeding strategy for dog breeders during the last 200 years. However, its negative effects on fer-tility and other fitness traits, a phenomenon called inbreeding depression, have been ignored in the quest of perfect unity in conformation or performance. The purpose of this study was to test the hypotheses that Litter size is reduced as a consequence of in-breeding, affected by both the inbreeding coefficient of the dam and the litter and that a rapid increase in the inbreeding coefficient affects Litter size more than a slower rate. Data were collected from the Swedish Kennel Club registry of origin. Breeds included in the study were the Bernese Mountain Dog, the Cocker Spaniel, the Golden Retriever, the Rottweiler and the West Highland White Terrier.

Djupströbädd -bra för miljö och djur?

Deep litter is a system for animals kept in separate stalls, loafing and bedding in wind shelters. The litter can consist of different bedding, like straw and peat. The system is allowed to build over and to ensure optimal proportions it is necessary to add new straw regularly and to have good conditions. Important conditions are aerobic state, humidity, amount of organic substance and acceptable temperatures in the litter. The micro organisms are depending on temperature for their living conditions and to get the bottom layer in the litter to start burning.

Unga grisars sociala beteende : hur uppfattar de varandra

Studies on wild boars have shown that piglets at 10 to 12 days of age can be introduced to pigs outside the litter without fighting. In today's production systems, the litters are kept in separate pens until weaning. At that point, the litter is divided and the piglets are placed together with piglets from other litters. This usually leads to aggressions among the piglets and may cause stress. This literature review aims to find out how piglets perceive other pigs in their surroundings.

Skördesystem i vall, skördens storlek ochfoderkvalitet

The choice of harvest date for leys is one of the most important factors affecting the size and quality of the harvest. An early harvest gives a high nutritive value while a late harvest gives larger quantity. Today?s aim to produce high nutritive leys gives early harvest dates both in primary growth and regrowth in northern part of Sweden. The consequence is a growth in the autumn, a "third harvest".The aim of this master thesis was to study the effects of different harvesting systems and their effect on size, feed quality, wintering and economy for conditions in the northern part of Sweden.

Blodglukosmätarens betydelse vid mätning i hemmet på katter med diabetes mellitus

The choice of harvest date for leys is one of the most important factors affecting the size and quality of the harvest. An early harvest gives a high nutritive value while a late harvest gives larger quantity. Today?s aim to produce high nutritive leys gives early harvest dates both in primary growth and regrowth in northern part of Sweden. The consequence is a growth in the autumn, a "third harvest".The aim of this master thesis was to study the effects of different harvesting systems and their effect on size, feed quality, wintering and economy for conditions in the northern part of Sweden.

Genes involved in ovulation rate and litter size in sheep

Fertilitetsegenskaper har ofta låga arvbarheter och selektion baserat på fenotyp är ofta ineffektiv och långsam. För att förbättra fertilitetsegenskaper som ovulationsmängd och kullstorlek hos får är det effektivast att selektera avelsdjur utefter deras genotyp. Olika mutationer i gener tillhörande transforming growth factor-? (TGF?) superfamiljen har visat sig påverka ovulationsmängd och kullstorlek hos får. Dessa gener är BMPR-1B, BMP15 och GDF9.

Torvströ till svenska mjölkkor :

Peat litter is a soft material with high absorbency. About hundred years ago many farmers in Sweden used peat litter to their dairy cows. After the World War II the use of peat litter decreased and the farmers used more straw. Nowadays (year 2007), when it is harder to find straw and sawdust to buy, peat litter is advancing again. The purpose with this study is to investigate peat as a litter to dairy cows.

Aktivitet, läggnings- och resningsbeteenden, tillväxt samt renlighet hos kvigor i liggbås respektive djupströbäddsbox :

The aim of this study was to compare activity, lying down and getting up behaviour, weight gain and cleanliness in heifers in cubicles versus on deep-litter. The study was conducted from autumn of 2005 until autumn of 2006 in a commercial organic dairy herd with 340 cows. In 2005 the farm rebuilt half of the young stock accommodation from deep-litter pens to cubicles. The experiment used 150 heifers of the breeds Swedish Red, Swedish Holstein and crossbreeds between these, all born on the farm. The animals were divided into three blocks based on breed and within each block they were sorted after increasing age. The youngest heifer in each block was randomly allocated to one of two groups, cubicle or deep-litter pen.

Management factors influencing sow productivity in successful Swedish and Danish herds

The number of weaned piglets per sow and year is a good measurement of sow productivity since it is affected by the number of piglets born alive, the pre weaning mortality (i.e. mortality of live born piglets between birth and weaning) and the number of litters per sow and year. This measure is also closely connected to the number of piglets produced per year, which partly determines the profitability of the piglet producer. During this study, eleven successful piglet-producing herds were visited. Eight of the producers were Swedish and three of the producers were Danish.

Strötorvsanvändning i djurstallar : en litteraturgenomgång

Peat litter has been used in animal houses for a long time. Because of its good ability to absorb liquid and nutrients from the manure it can create a dry surface for animals and a valuable manure product. Through changes in agricultural practises the use of peat litter has diminished and is to a great extent replaced by straw, sawdust and cutter shavings although Sweden is rich in peat-findings. The aim of this work was to summarize the presented knowledge about the used of peat litter, techniques, advantages and disadvantages and to compare with other commonly used litter materials. Articles on peat litter have been searched for in magazines, databases and books at SLU library. Visits to peat industries, interviews with peat producers and with peat researchers contributed to the material. Peat is not a uniformly material.

Honlig reproduktionsfysiologi hos lodjur (Lynx lynx)

Knowledge in reproduction in the Swedish lynx (Lynx lynx) is important forseveral reasons. Situated on top of the food chain, lynxes may be at risk of beingexposed to environmental toxins that could have adverse effect on reproduction.The population of lynxes is today managed by restricted hunting which demandsknowledge about both the lynxes numbers and their reproduction. In addition,lynxes may function as indicators of climate change for instance if their season ofheat would be earlier or prolonged due to a warmer climate. Today?s knowledgein reproduction in Swedish lynx is mainly based on information gathered fromradio collared animals.

Beror KRAV-grisars ledanmärkningar på miljöfaktorer?

This project investigated how elevation and vegetation type influences variation in plant litter phenolic content and protein precipitation capacity among and within common plant species for two different vegetation types, heath and meadow, in a subarctic ecosystem in the Abisko region of northern Sweden. As nutrient availability generally decreases with increasing elevation as a result of decreasing temperature, I hypothesised that phenolic content would increase with elevation and be higher on the heath than the meadow. To test this, the total phenolic content and protein precipitation capacity was estimated in leaf litter from 13 species in both heath and meadow vegetation across an elevational gradient ranging from 500 to 1000 meters above sea level (m.a.s.l.) in the study region. The results showed that elevation and vegetation type both had a strong impact on both variables. Total phenolic concentrations decreased with elevation for the meadow, and were greater for the heath than the meadow.

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