961 research outputs found
Haptoglobin and serum amyloid A in relation to the somatic cell count in quarter, cow composite and bulk tank milk samples
Milk somatic cell count (SCC) is the gold standard in diagnosis of subclinical mastitis, and is also an important parameter in quality programmes of dairy cooperatives. As routine SCC analysis is usually restricted to central laboratories, much effort has been invested in the search for alternative biomarkers of mastitis and milk quality, including the presence in the milk of the acute phase proteins (APP), haptoglobin (Hp) and serum amyloid A (SAA). The aim of this study was to investigate relationships between Hp, SAA and SCC in quarter, cow composite, and bulk tank milk samples. Cows (n=165), without any clinical signs of disease or abnormalities in the milk or udder, from three different dairy farms, were used. Cow composite milk samples from all cows delivering milk at the sampling occasion were taken once in each herd. In one of the farms, representative quarter milk samples (n=103) from 26 cows were also collected. In addition, bulk tank milk samples from 96 dairy farms were included in the study. Samples were analysed for Hp, SAA and SCC, and relationships between the parameters were evaluated at quarter, cow and tank milk levels using Chi-square analysis. Milk samples were categorized according to their SCC, and the presence, or no presence, of SAA and Hp, based on the detection limits of the screening methods (0.3 mg/l and 1.0 mg/l for SAA and Hp, respectively). Hp and SAA were found in milk at quarter, cow composite and bulk tank levels. A large proportion (53%) of the animals had detectable milk concentrations of APP, and SAA was detected more frequently, and at higher concentrations than Hp, regardless of sample type. SAA was detected in as many as 82% of the bulk tank milk samples. Significant relationships were found between Hp, SAA and SCC at quarter and cow composite milk levels, but only between SAA and SCC at bulk tank milk level. Detectable levels of APP were more common at high SCC
Bovine acute phase proteins in milk
The composition and quality of the raw milk is essential for the dairy industry and since only healthy cows produce milk of high quality, it is important with prospering cows. The most important and common disease among dairy cows is mastitis (inflammation of the udder). Mastitis is not only an animal welfare problem, but also results in impaired milk quality, reduced product yield, higher production costs and consequently a higher price for the consumer. The most common way to detect subclinical mastitis is by measuring the somatic cell count (SCC). The SCC is also an important parameter in milk payment systems, highly affecting the price to the producer. Since SCC is influenced by other factors than mastitis, e.g. lactation number, stage of lactation, stress etc., there is a need for new biomarkers for detection of subclinical mastitis as well as for raw milk quality. The aim of this thesis was to obtain further knowledge about the occurrence of the two major acute phase proteins (APP) in bovine milk, haptoglobin (Hp) and serum amyloid A (SAA), and to evaluate their potential as biomarkers for raw milk quality. For the first time, a method for analysis of Hp using an optical biosensor based on surface plasmon resonance (SPR) technology was developed. The method is fully automated with no need for sample preparation before analysis and each sample requires approximately 8 minutes. The occurrence of Hp and SAA in quarter, cow composite and bulk tank milk samples were investigated and the results showed that APP could be detected in all types of samples. In general, detectable levels of APP in milk were related to high SCC, probably originating from cows with subclinical mastitis. In general, samples containing APP had lower casein content, casein number (casein in relation to total protein) and lactose but also increased whey protein content or increased proteolysis. Hp and SAA were suggested to be useful biomarkers for milk quality, especially the protein quality. To our knowledge, this thesis is the first describing Hp and SAA as potential biomarkers for raw milk quality
An Indirect ELISA for Detection of Encephalitozoon cuniculi Infection in Farmed Blue Foxes (Alopex lagopus)
Infection with the intracellular microsporidium Encephalitozoon cuniculi can cause serious disease, encephalitozoonosis, in the blue fox (Alopex lagopus). The disease diagnosis is based on clinical signs and pathological findings, and detection of E. cuniculi or circulating antibodies directed against the parasite. Indirect immunofluorescence (IFAT) and carbon immunoassay (CIA) are the most commonly used serological methods for diagnosis in this species. In the present study, an indirect ELISA (enzyme linked immunosorbent assay) was established and evaluated against IFAT by testing of 205 field samples from blue foxes. There was high agreement between the results of the ELISA and CIA (κ = 0.99), and the ELISA and IFAT (κ = 0.958). There was no significant statistical difference between the tests (p > 0.05). It was concluded that the ELISA could be used to identify seropositive farmed blue foxes. The advantage of the ELISA lies in the potential of screening large numbers of animals with the goal of eradicating E. cuniculi infection in the farms
Biosensor assay for determination of haptoglobin in bovine milk
Despite more than 30 years of research into mastitis diagnostics, there are few alternatives to the somatic cell count (SCC) in practical use for identification of cows with subclinical mastitis. Mastitis is not only an animal welfare problem, but also affects the yield, composition and technological properties of milk. Hence, dairy cooperatives give farmers a premium quality payment to encourage low SCC although there is no clear scientific data defining the level of SCC in bulk tank milk that is associated with additional benefits in terms of milk quality. Recent research on alternative markers for inflammatory reactions in the lactating cow, e.g. in mastitis, includes investigations of the acute phase protein, haptoglobin (Hp). So far, the content of Hp in milk has mainly been studied in relation to mastitis diagnostics, with little attention given to its importance for milk composition and technological properties. At present, Hp in milk is measured using ELISA, but this technique is not suitable for routine large-scale analysis. In recent years, optical biosensor technology has been used for automated and rapid quantitative analysis of different components in milk, but so far not for analysis of acute phase proteins. The aim of the present study was to develop a rapid and sensitive biosensor method to determine Hp in milk. An affinity sensor assay based on the interaction between Hp and haemoglobin was developed using surface plasmon resonance (SPR) biosensor technology. The assay was used to analyse Hp in composite milk samples from cows without any clinical signs of mastitis and quarter milk samples with a weak to strong reaction in the California Mastitis Test (CMT). A commercial ELISA for determination of Hp in milk was used for comparison. The limit of detection (LOD) of the biosensor assay was determined as 1.1 mg/l. Within-assay and betweenday variations were determined both with bulk tank milk spiked with human Hp and with composite milk samples containing bovine Hp. Coefficients of variation varied between 3.6 and 8.6% at concentrations between 4.0 and 12 mg/l, respectively. Agreement between the results obtained by the biosensor assay and the ELISA was satisfactory ; however, the results obtained by the biosensor were generally lower than the results obtained by the ELISA. Possible explanations for this observation are discussed
Bacteriological Investigation of Infectious Keratoconjunctivitis in Norwegian Sheep
Contagious keratoconjunctivitis is a rather common disease in Norwegian sheep. Since the knowledge of its aetiology is limited, the present study was performed to determine the microorganisms involved. Local veterinarians throughout the country collected conjunctival swabs from both sick (n = 43) and healthy (n = 42) sheep on 15 farms with outbreaks of ovine keratoconjunctivitis, and further from healthy sheep (n = 50) on 17 farms not showing any signs of conjunctival disease. All samples were cultivated for bacteria and mycoplasma. Listeria monocytogenes was isolated from 3 cases (1%) in one single herd. Staphylococcus aureus (5%), Corynebacterium spp. (2%) and Escherichia coli (4%) were isolated only in herds with keratoconjunctivitis, but from both sick and healthy animals. Moraxella (Branhamella) ovis was isolated from 28% of sampled animals in affected herds and from 10% of sampled animals in healthy herds. The corresponding numbers for Moraxella spp. were 9%/12%, for Pseudomonas spp. 7%/8%, for Staphylococcus spp. 22%/22%, for Bacillus spp. 12%/14%, for Micrococcus spp. 6%/2% and for Streptococcus/Enterococcus spp. 2%/2%. Mycoplasma conjunctivae was isolated from 16 animals with keratoconjunctivitis (37%) and from 3 animals without clinical signs (7%) in farms with keratoconjunctivitis. In farms without clinical signs of keratoconjunctivitis, M. conjunctivae was isolated in 4 animals (8%). To our knowledge, this is the first time M. conjunctivae has been isolated in Norway. Other predisposing agents found were Moraxella (Branhamella) ovis and Listeria monocytogenes. The etiological importance of different microorganisms in ovine keratoconjunctivitis seems to vary; some are probably only present as secondary invaders. Other possible causes of ovine keratoconjunctivitis in Norway, such as Chlamydia psittaci, remain to be investigated
Relationship between haptoglobin and serum amyloid A in milk and milk quality
The objective of this study was to evaluate relationships between the presence in milk of the major bovine acute phase proteins, haptoglobin (Hp) and serum amyloid A (SAA), and milk quality parameters. Composite milk samples were collected from 89 clinically healthy dairy cows and analysed for Hp and SAA, total protein, casein, and whey protein levels, casein number, proteolysis, total fat and lactose levels, and somatic cell count (SCC). Milk samples with detectable levels of Hp showed lower total protein and casein levels, whereas milk samples with detectable levels of SAA had lower casein number and lactose level. Samples with detectable levels of acute phase proteins also showed an elevated SCC. The results suggest that the presence of Hp and SAA in milk might indicate unfavourable changes in milk composition, especially in relation to protein quality
Förändras mjölkens proteinsammansättning i separata juverdelar i samband med höga celltal (SCC)?
Today the milk production per cow is increasing but the milk delivered by the Swedish farmer contains less amounts of fat and protein than earlier. The contents have decreased since 1993. In average the milk contain 4,2 percent fat and 3,4 percent protein. Earlier the fat content in milk was important. Nowadays the dairy's attention has turned to the milk's valuable proteins, principally the caseins, which have a considerable nutritional value and are important for several dairy products like cheese and yoghurt.
An inflammation in the udder which injuries the udder tissue is called mastitis. Mastitis is a big problem among dairy cows. The immune system become activated when the cow gets mastitis which cause an increased somatic cell count in the milk and also changes in the milk composition. Mastits cause economical losses for the farmer, health problem for the cow and also problem for the dairy industry.
Knowledge about different factors affecting the composition of the milk is therefore very important. The purpose of this study was mainly to investigate how the protein composition in milk was affected in connection with an increased somatic cell count (SCC). Except the protein composition even parameters like fat, lactose and milk yield have been studied. Compared to many other investigations this study was based on milk samples from each separate udder quarter. During a subclinical mastitis, when milk is not visually affected, is it especially important to collect samples from each quarter to avoid the dilution from the other healthy quarters.
The study was conducted on Kungsängen research station at the Department of Animal Nutrition and Management, Swedish University of Agricultural Sciences, Uppsala. The cows participating in the study were from the ordinary research stock. 24 cows participated in the study, 12 of these participated twice. 18 of the 24 cows were milked in an AMS (automatic milking system) while the rest of the cows were in conventional stables. 140 quarter milk samples were collected at seven occasions.
To get a rough estimation about the cell count in the milk CMT (California Mastitis Test) was used, but all samples have also been analysed with electronic fluorescensbased cellcounting to get a more precise value of the cell count in the milk. This information was then used to decide which quarter that had an increased somatic cell count compared to the opposite quarter. To precipitate the casein the rennet method was used. Both the milk and the serum protein have then been analysed on the FTIR (Fourier Transform Infrared Spectroscopy) to get values for the fat- lactose- and protein content. To decide the casein content an indirect method has been used. The difference between the protein content in whole milk and in the protein content in the serum protein fraction have been calculated to get a value for the casein content in the milk.
Most of the cows participating in this study had a very good udder health. Despite a low somatic cell count it was possible to detect several changes in the composition when a quarter had an increased SCC. The results from this study revealed that casein, casein number (casein: total protein), milk yield and lactose decrease significant with an increase in SCC. The whey protein increased significant. The fat content and the total protein content had some tendency to increase with an increased SCC, but these results were not significant. The amount of milk decreased with 23-24 %, lactose decreased with 4-5 % while the serum protein increased with 7-8 %. The casein number decreased with 2,5 % in a quarter with an increased SCC. Maybe 2.5 % sound negligble but because the casein number is a quotient between the casein content / total protein content such a decrease can have a considerable effect for the cheese making industry.Dagens kor mjölkar allt mer men mjölken som Sveriges bönder levererar till mejerierna innehåller allt lägre halter av fett och protein. I genomsnitt innehåller mjölken 4,2 procent fett och 3,4 procent protein. Information om innehållet av mjölkens proteiner, främst kaseinerna, har i dag fått större uppmärksamhet än tidigare då fetthalten var av stort intresse. Kaseinerna är viktiga på grund av deras näringsvärde samt deras betydelse vid framställning av mejeriprodukter såsom ost och yoghurt.
En inflammation i juvret, som leder till att juvervävnaden skadas, kallas mastit. Mastit är ett stort problem hos mjölkkor i dag. Vid mastit aktiveras immunförsvaret, vilket leder till ett ökat celltal i mjölken och förändringar i mjölkens sammansättning. Detta innebär ekonomiska förluster för lantbrukaren, i vissa fall lidande för djuret, samt problem för mejeriindustrin.
Kunskap om olika faktorer och hur dessa påverkar mjölkens sammansättning är därför mycket viktig. Syftet med denna studie var framförallt att undersöka hur mjölkens proteinsammansättning påverkas av ett förhöjt celltal. Förutom proteinsammansättningen har även parametrar såsom fett, laktos och mjölkmängd studerats. Till skillnad mot många andra studier har denna utförts på juverfjärdedelsnivå. Vid subkliniska mastiter, då mjölken visuellt inte är förändrad, är det speciellt viktigt att ta prover från varje juverdel för att undvika utspädning från de friska juverdelarna.
Studien genomfördes vid Kungsängens forskningsstation, Institutionen för husdjurens utfodring och vård, Sveriges Lantbruksuniversitet, Uppsala. Korna som ingick i studien valdes ut från den ordinarie försöksbesättningen. 24 kor ingick i studien, 12 av dessa var med i två provtagningsomgångar. 18 av de 24 korna som ingick i studien var inhysta i stallet med automatiskt mjölkningssystem (AMS) medan de övriga var inhysta i konventionellt stall. Vid sju provtagningstillfällen har 140 juverdelsprover insamlats, vid fyra tillfällen ingick trespenta kor.
För att få en grov uppskattning av celltalet i mjölken har CMT (California Mastitis Test) använts, men alla prover har även blivit analyserade med hjälp av elektronisk fluorescensbaserad cellräkning för att få ett noggrannare värde på mjölkens innehåll av celler. Detta för att kunna bestämma vilka juverdelar som hade ett förhöjt celltal. För att fälla ut kaseinet i mjölken har löpemetoden använts. Både mjölken och vasslen har därefter analyserats på FTIR (Fourier Transform Infrared Spectroscopy) för att erhålla värden på dess innehåll av fett, laktos och protein. För att bestämma kaseininnehållet i mjölken har en indirekt metod använts. Differensen mellan proteininnehållet i helmjölken och i vasslefraktionen har beräknats och på så sätt har man kunnat erhålla mjölkens innehåll av kasein.
De flesta korna som ingick i denna studie hade en mycket god juverhälsa, men trots detta kunde man vid relativt låga celltal även upptäcka förändringar i mjölken. Resultaten från denna studie visar att kasein, kaseintalet, mjölkmängd och laktos minskar signifikant vid ett förhöjt celltal. Vassleinnehållet ökar däremot signifikant. Fett och totala proteininnehållet tenderar till att öka vid ett förhöjt celltal, men dessa resultat var dock ej signifikanta. Mjölkmängden minskade med 23-24 %, laktos minskade med 4-5 % medan vassle ökade med
8-9 %. Kaseintalet minskade med ca 2,5 % på juverdel som hade ett förhöjt celltal, vilket kan verka obetydligt, men i och med att kaseintalet är en kvot mellan kaseininnehåll / totala proteininnehållet kan en sådan minskning ha en betydande effekt för bl.a. ysterierna
Implementering av markfuktighetskartor
Ett nytt verktyg som tagits fram för att förenkla drivning och drivningsplanering är markfuktighetskartor. Med hjälp av dessa kan blöta eller fuktiga partier i terrängen identifieras och därmed förenkla placering av exempelvis basvägar eller naturhänsyn. När ett nytt verktyg eller arbetssätt implementeras finns risk att möta motstånd eller missnöje.
I den här studien undersöks implementeringsprocessen av markfuktighetskartor hos företaget Sydved AB för att förstå hur information, utbildning och användning av kartorna upplevs av berörda maskinförare. I studien har 13 maskinlag, om totalt 23 maskinförare, intervjuats liksom Sydveds projektledare för implementeringsprocessen.
Resultatet visar att majoriteten av maskinförarna är nöjda med den information och utbildning som tillhandahållits. De få anledningarna till missnöje kring processen är upplevelser av låg insyn i processen och svag känsla av delaktighet. Majoriteten av maskinförarna använder markfuktighetskartan. De vanligaste anledningarna att inte använda markfuktighetskartan är att det tar tid att lära sig tolka den samt att den är svår att orientera sig i. Majoriteten ser dock nytta i att använda kartan samt ser denna som ett verktyg de kommer använda i framtiden. I första hand anses markfuktighetskartan kunna underlätta drivningsplaneringen.One of the new technical tools within the forestry sector is the soil moisture map. The soil moisture maps in Sweden is based on a 3D model developed from airborne laser scanning. The 3D model, a digital elevation map (DEM) can be used to calculate water flows within a landscape. Wet or moist areas are then visualized as blue areas in the map.
When a new tool or a new way of working is implemented there is a risk of encounter resistance or disaffection. There could be a lot of courses to disaffection, for example uncertainty of requirement, fear of changing or fear of not be able to change. Two important factors when changing are learning processes and motivation. Learning is important on both individual and organizational level. Learning requires feedback and room for mistakes. Organizations often want to increase motivation among the workers. With higher motivation, the chances to individual progress increases as well as the quality of performed work.
This study investigates the implementation of soil moisturemaps at the Swedish forest company Sydved AB. The process includes information, education and utilization and how these parts are experienced by machine operators. The study is based on 13 interviews of machine operator groups and the project leader at Sydved AB, in total 24 persons.
The results show most of the machine operators are pleased with the information and education about the soil moisture maps. Further, most of them use the soil moisture map when planning a logging operation. But there is some disaffection as well. For example, a few machine operators experience low level of insight in the implementation process and a low feeling of participation. One reason not to use the map is that it takes time to learn how to interpret the map. On the other hand, all machine operators see the soil moisture map as a helpful tool they will use in the future. There are demands on further education and follow-ups to further implementation of the map.
The main conclusions are:
The implementation process of soil moisture map that is used by Sydved get generally positive criticism from machine operators. Important factors are to present satisfying information and education. It is important to make the change make sense for those who are supposed to change. This process requires motivation and room for learning and feedback.
The soil moisture map is an advanced tool that can simplify the machine operators work, especially when planning logging operations. The soil moisture map can also be used to explain risks for ground damages to land owners, or help to warrant longer strip roads or use of adjacent land owned by someone else.
A well-planned implementation process is important when introducing a new way of working or a new working tool. Information and education are important factors as well as monitoring the process. To meet disaffection are a challenge but should be kept in mind. The disaffection could tell a lot of the organisation and its way of working
Acute toxoplasmosis in three wild arctic foxes (Alopex lagopus) from Svalbard; one with co-infections of Salmonella Enteritidis PT1 and Yersinia pseudotuberculosis serotype 2b
Prospective study of job stress and risk of infections in Swedish adults
ObjectivesPsychological stress may influence both susceptibility and severity of infections. Although work-related stress is a widespread concern among many employees, few studies have been conducted with the focus on work stressors and infections. We therefore aimed to investigate this association in a prospective cohort study.MethodsOur study included 25 029 employed individuals who filled-out a questionnaire in September 1997 and were followed through record linkages until retirement or December 2016. Work stress was assessed at baseline using a Swedish version of the Demand-Control Questionnaire, whereas hospital contacts related to infections were identified from the National Patient Register. We fitted extensions of the standard Cox model to account for recurrent infections.ResultsIn total, we observed 8257 infections. Individuals in the third tertile of job demand had a 13% higher hazard of infections (HR=1.13; 95% CI=1.03 to 1.24) compared with individuals in the first tertile, specifically an increased incidence of upper respiratory tract infections (HR=1.15; 95% CI=1.00 to 1.33) and urinary tract infections (HR=1.31; 95% CI=1.09 to 1.57) was found. Employees with the highest job control (third tertile) had no lower risk of infections than individuals in the lowest tertile (HR=1.02; 95% CI=0.92 to 1.13). When combining the demand and control dimensions into job strain scale, no association between high job strain and infections was observed (HR=1.08; 95% CI=0.97 to 1.21).ConclusionHigh job demand, but not low job control, is associated with an increased occurrence of infections. No difference was observed in workers with high strain jobs compared with those with low strain jobs
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