Dispersioonikomponentide ja päritavuskoefitsiendi hindamine loomapopulatsioonides

http://tartu.ester.ee/record=b1019137~S1*es

The yield and quality of milk on the farms using twice a day conventional milking in comparison with the farms using three times a day conventional and automatic milking systems

The objective of this study was to compare milk parameters during lactation months on farms using automatic (ALS) and conventional milking systems (PLS). The highest milk yield per cow (30.1 kg) was obtained on 3x PLS farms, whereas cows on 2x PLS farms produced 7.7 kg less milk. Milk yield of the cows on ALS farms (24.8 to 26.3 kg) was between that of 2x PLS 2 and 3x PLS farms. On Robot 1 ALS farms the milk yield of cows was by 1.5 kg higher compared to Robot 3 ALS farms (24.8 kg). Milk yield increased until the second month of lactation on all the farms, and decreased subsequently. The difference in milk yield between 2x and 3x PLS farms increased until the third month of lactation, whereas it was by 8.8 to 9.9 kg higher in 3x PLS until the ninth month of lactation, and decreased subsequently (8.6 to 9.4 kg). All ALS farms showed more uniform results. Higher milk yield resulted in lower milk fat (r = –0.36) and milk protein (r = –0.42) content. The highest somatic cell score (SRS) (3.81) was found in the milk obtained from 2x PLS, whereas increased milking frequency decreased SRS by 0.48. Milk SRS was the lowest (2.88) on Robot 1 ALS farms, and the highest on Robot 2 (3.66) ALS farms. Irregular milking on ALS farms did not cause higher SRS of milk, compared to PLS. Increase in milking frequency resulted in higher milk yield and lower SRS, milk fat and milk protein content, whereas ALS and PLS farms showed similar trends. Decrease in milk yield was linear during lactation

Additional concentrates do not affect feeding times of cows, but social positions of cows do

ArticleIn robotic milking dairy systems lack of control over intakes can be problematic for balancing the forage and concentrate portions of diets. This can lead to proble ms associated with high concentrate intakes and concomitant low forage intakes. To check this as a problem, the feeding behaviour of cows was observed: the number of daily visits to the feed barrier, the duration of these visits and actual feeding, of high and low yielding cows. The cows were robot - milked and fed a ration comprising, separately, concentrate feed from a robot and a feeder, and a grass/clover silage mix forage at the feed barrier. Individual variation in visiting times and times spent at the feed barrier were greater than the effect of level of production. There was no evidence that cows with higher milk yields are differentially motivated to feed from forage. But more dominant cows spent more time feeding than submissive cows

Low cholesterol levels in children predict impulsivity in young adulthood

Objective: Severe behavioural issues such as impulsive action and suicide have since long been associated with low levels of cholesterol. While it is known that cholesterol plays a role in neural development and hence low levels of serum lipids could have long-term effects on behaviour, there are no longitudinal studies showing association of serum lipids levels with impulsivity. We aimed to examine the prognostic properties of serum lipid levels during childhood and adolescence on measures of impulsivity during early adulthood in a representative birth cohort sample. Methods: We have investigated whether serum lipid levels measured at 9, 15, 18 and 25 years of age have an association with impulsivity in 25 years old young adults. This analysis was based on data of the birth cohort representative samples of the Estonian Children Personality Behaviour and Health Study (original n=1238). Impulsivity was self-reported with the Adaptive and Maladaptive Impulsivity Scale. Results: Total and LDL cholesterol measured in 9, 15 and 18 years old boys predicted Disinhibition and Thoughtlessness in 25 years old young adults. High scores of Disinhibition were associated with low total and LDL cholesterol levels in males but, while less consistently, with high total and LDL cholesterol levels in females. Cross-sectional analysis did not result in systematic outcomes. Conclusions: Serum lipid levels could have an impact on development of maladaptive impulsivity starting from an early age. This effect of cholesterol continues throughout adolescence into young adulthood

Changes in dairy cows' behaviour, health, and production after transition from tied to loose housing

BackgroundTransition of dairy cows from a tied to a loose housing system may affect their behaviour, health and production. Such housing system changes have become more frequent in Estonia but knowledge is lacking on how cows adapt to a new system. The aim of this study was to evaluate how cows' behaviour, milk production and composition, and different aspects of their health changed after transition from tied to loose housing.ResultsA herd of 400 dairy cows was moved to a new system on the same farm, so that effects of transport were not confounding factors. Behavioural observations were made for approximately 4 months following transition. Milk production data were recorded from 12 months before to 12 months after transition. Examination for skin alterations and cleanliness, as well as body condition scoring were carried out before transition, and thereafter monthly throughout the study. Significant effects on behaviour were observed just after the transition, with increases in the behaviour indicative of poor welfare, such as vocalisation and aggression, and decreases in those indicative of a good state of welfare, such as ruminating, resting and grooming. These effects were of short duration, with most returning to a steady state after the first week. Milk production declined already before the transition but fell significantly after transition, and this fall lasted longer in older cows. Likewise, somatic cell counts were higher in all cows following transition, but older cows were affected significantly more than cows in the first lactation. The frequency of lameness and skin alterations increased on average after transition. Body condition scores fell after transition but recovered by the second month. Therefore, there were adverse effects on the behaviour, health and production of the dairy cows transferred, although, apart from older cows, of short duration.ConclusionThe transition from tied to loose housing first had negative impacts on the welfare of the cows, although by the tenth day the behavioural indicators had returned to normal values. Impacts were more severe in higher parity cows, indicating that the change was more of a challenge for older cows.The findings of this study suggest that animals' behaviour and health should be more carefully observed within about 2 weeks after transition. It is quite likely that more and more farmers in Estonia and elsewhere will recognize the benefits of keeping their dairy cattle in loose housing, aimed at improving animal welfare and the value of the production chain

Reliability of the entomovector technology using Prestop-Mix and Bombus terrestris L. as a fungal disease biocontrol method in open field

Botrytis cinerea Pers.: Fr. is a major plant pathogen, and a new approach is needed for its control in strawberry to minimise the increasing use of synthetic fungicides. The biofungicide Prestop-Mix, which contains Gliocladium catenulatum, is effective against Botrytis infections; however, the need for frequent applications increases the costs for farmers. Here, we demonstrate that bumble bees, Bombus terrestris L., effectively disseminate the preparation onto flowers in open field conditions. Over the course of three years, we found a highly significant decrease in the rate of Botrytis infection. Pathogen control was achieved with relatively low numbers of G. catenulatum spores per flower, even using flowers that are not highly attractive to bumble bees. An even distribution of spores was detected up to 100 m from the hives, either due to primary inoculation by bumble bees or secondary distribution by other flower visitors such as honey bees and solitary bees. We showed that the application of a biocontrol agent by bumble bees is reliable for the use of environmentally friendly pest control strategies in northern climatic conditions. This low cost technology is especially relevant for organic farming. This study provides valuable information for introducing this method into practice in open strawberry fields

Antimicrobial Selection for the Treatment of Clinical Mastitis and the Efficacy of Penicillin Treatment Protocols in Large Estonian Dairy Herds

Clinical mastitis (CM) is the most common microbial disease treated in dairy cows. We analyzed the antimicrobial usage in cows with CM (n = 11,420) in large dairy herds (n = 43) in Estonia. CM treatment data were collected during a 12-month study period. The antimicrobial usage was observed during the 21 days from the initiation of treatment, and the incidence of antimicrobial-treated CM was calculated for each study herd. The effect of intramammary (IMM), systemic, and combined (systemic and IMM) penicillin treatment of CM on the post-treatment somatic cell count (SCC) was analyzed using the treatment records of 2222 cows from 24 herds with a mixed multivariable linear regression model. The median incidence of antimicrobial-treated CM was 35.8 per 100 cow-years. Procaine benzylpenicillin and marbofloxacin were used in 6103 (35.5%, 95% CI 34.8–36.2) and 2839 (16.5%, 95% CI 16.0–17.1) CM treatments, respectively. Post-treatment SCC was higher after IMM penicillin therapy compared to systemic or combination therapy. Treatment of CM usually included first-choice antimicrobials, but different antimicrobial combinations were also widely used. The effect of procaine benzylpenicillin to post-treatment SCC was dependent on the administration route, cow parity, and days in milk. Further studies should evaluate the factors affecting veterinarians’ choice of antimicrobial used in the treatment of CM

Resistance developments in Estonia’s population of pollen beetles (Brassicogethes aeneus)

A total of 111 local pollen beetle populations were collected from both winter and spring oilseed rape fields, in the main oilseed growing regions of Estonia between 2015−2019. The objective was to analyse the insecticide-susceptibility of the pollen beetle population (in the form of Brassicogethes aeneus). The pollen beetle samples were tested for sensitivity to lambda-cyhalothrin, thiacloprid, and chlorpyrifos. The efficacy of the tested insecticides varied considerably by region. We observed a clear decrease in susceptibility to lambda-cyhalothrin and thiacloprid, but sensitivity to chlorpyrifos remained stable throughout the period between 2015 and 2019. Amongst the tested samples in that period, a total of 3% were classified as susceptible to lambda-cyhalothrin, 18% as moderately resistant, 70% as resistant, and 7% as highly resistant. In the case of thiacloprid, 21% of the samples were highly susceptible to the insecticide, 39% were susceptible, and 41% had reduced levels of susceptibility to the insecticide. The information which was presented tended to confirm the ongoing evolution of insecticide resistance in the B. aeneus population in Estonia, while also highlighting the importance of data-based decisions when optimising insecticide resistance management in the field

The effect of ageing on chosen quality characteristics of skeletal muscles of Aberdeen Angus bulls

ArticleThe objective of the trial was to study the qualitative parameters of two muscles of Aberdeen Angus bulls with 250–300 kg carcass weight. After slaughter, longissimus thoracis et lumborum (LD) muscle and unseparated semimembranosus and adductor femoris(SMA) muscles were removed from the chilled carcasses. Muscles were vacuum-packed and wet aged at +2 °C for 10, 14, 18 and 20 days. Meat pH, electrical conductivity, shear force and colour were measured in all ageing times. Two thermal treatment methods (sous-vide (SV) and grilling) were used to determine cooking losses. The effects of muscles, ageing times and muscles by ageing times interaction was found with two-factorial analysis of variance. The effects of muscles, ageing times and muscle groups by ageing time interaction for raw and SV treated meat shear force was significant. Ageing decreased SV treated meat shear force from day 10 (40.8 N) to 18 (29.7 N). Fresh and SV treated LD muscle was tougher compared to the SMA muscle group, but SM showed a better response to the tenderness within 20 days of ageing. Redness and yellowness value was higher in the SM group in comparison to LD. Muscles showed good colour (lightness, redness and yellowness) stability within ageing for 20 days. No interactions were found between muscle groups and ageing times for SV treated and grilled beef cooking losses. However, SV treated meat lost more weight than grilled meat slices. The present study suggests that the optimal ageing time for meat is 18 days when the grilled meat cooking loss is the lowest