Incidence of boar taint in Swedish Landrace and Yorkshire boars     

Birgitta Malmfors  Ingemar Hansson 《Livestock Production Science》1974,1(4):411-420

Boar taint in 500 Swedish Landrace and Yorkshire boar carcasses was tested by smelling fat samples heated on the tip of a soldering iron at 150°C. About 40% of the boars were scored as non-tainted; in another 40%, the judges were unsure whether taint was present or not. Boar taint was judged present in only 20% of the boars.The effects of weight and sex on boar taint were studied in approx. 275 boars, barrows and gilts slaughtered at 70, 90, 110 and 130 kg live weight. The number of boars scored as tainted increased with weight, but weight did not affect the level of taint in all boars. When the taste of boar meat and fat was compared to castrates, no differences were found in 80% of comparisons at 70 or 90 kg.The effect of weight on boar taint was studied in 69 boars reared on ad libitum or restricted feed. Biopsies were taken, by a needle biopsy technique, at 70, 90 and 100 kg live weight. The incidence of boar taint did not increase from 70 to 100 kg when boars were on restricted feed, but the weight effect was significant and linear at the ad libitum feeding level. The cause was probably an interaction between physiological development, age and weight of the boars.  相似文献   

The influence of the PRKAG3 mutation on glycogen,enzyme activities and fibre types in different skeletal muscles of exercise trained pigs     

Anna Granlund  Marianne Jensen-Waern  Birgitta Essén-Gustavsson 《Acta veterinaria Scandinavica》2011,53(1):20

Background

AMP-activated protein kinase (AMPK) plays an important role in the regulation of glucose and lipid metabolism in skeletal muscle. Many pigs of Hampshire origin have a naturally occurring dominant mutation in the AMPK γ3 subunit. Pigs carrying this PRKAG3 (R225Q) mutation have, compared to non-carriers, higher muscle glycogen levels and increased oxidative capacity in m. longissimus dorsi, containing mainly type II glycolytic fibres. These metabolic changes resemble those seen when muscles adapt to an increased physical activity level. The aim was to stimulate AMPK by exercise training and study the influence of the PRKAG3 mutation on metabolic and fibre characteristics not only in m. longissimus dorsi, but also in other muscles with different functions.

Methods

Eight pigs, with the PRKAG3 mutation, and eight pigs without the mutation were exercise trained on a treadmill. One week after the training period muscle samples were obtained after euthanisation from m. biceps femoris, m. longissimus dorsi, m. masseter and m. semitendinosus. Glycogen content was analysed in all these muscles. Enzyme activities were analysed on m. biceps femoris, m. longissimus dorsi, and m. semitendinosus to evaluate the capacity for phosphorylation of glucose and the oxidative and glycolytic capacity. Fibre types were identified with the myosin ATPase method and in m. biceps femoris and m. longissimus dorsi, immunohistochemical methods were also used.

Results

The carriers of the PRKAG3 mutation had compared to the non-carriers higher muscle glycogen content, increased capacity for phosphorylation of glucose, increased oxidative and decreased glycolytic capacity in m. longissimus dorsi and increased phosphorylase activity in m. biceps femoris and m. longissimus dorsi. No differences between genotypes were seen when fibre type composition was evaluated with the myosin ATPase method. Immunohistochemical methods showed that the carriers compared to the non-carriers had a higher percentage of type II fibres stained with the antibody identifying type IIA and IIX fibres in m. longissimus dorsi and a lower percentage of type IIB fibres in both m. biceps femoris and m. longissimus dorsi. In these muscles the relative area of type IIB fibres was lower in carriers than in non-carriers.

Conclusions

In exercise-trained pigs, the PRKAG3 mutation influences muscle characteristics and promotes an oxidative phenotype to a varying degree among muscles with different functions.  相似文献   

Birth weight,reproduction traits and effects of inbreeding in Nicaraguan Reyna Creole cattle     

Corrales R  Näsholm A  Malmfors B  Philipsson J 《Tropical animal health and production》2011,43(6):1137-1143

Reyna Creole cattle in Nicaragua comprise about 650 purebred animals, and the breed has been shown to have a high level of inbreeding. To characterize the breed, as basis for a conservation program, information from two herds on birth weight (BW, n = 1097), age at first calving (AFC, n = 449) and calving interval (CI, n = 1,347) was analysed. Overall averages were 27.8 kg for BW, 37.4 months for AFC and 424 days for CI. Large differences between the herds were observed for all traits. Thus, there would be opportunities for management interventions to improve reproduction results. The heritability for BW was 0.34. For CI, the heritability of 0.20 and the additive genetic standard deviation of 36 days were comparatively high values. No genetic variation was found in AFC. Estimated inbreeding effects were associated with large standard errors due to the small size of the data and incompleteness of pedigrees. Nevertheless, significant effects were shown of dam inbreeding level on all traits. For each percentage of increased inbreeding, BW decreased by 0.06 kg, AFC increased by 3.5 days and CI increased by 1.4 days. The effects of the inbreeding level of the individual itself were not significant. The relatively good reproduction traits of Reyna Creole cattle shown in this study, despite high inbreeding levels, will be supplemented with a characterization of milk production traits.  相似文献   

Characteristics of oestrous cycles in Holstein cross-bred dairy heifers: An evidence of delayed post-ovulatory progesterone rise     

Kornmatitsuk S  Kornmatitsuk B  Chantaraprateep P  Larsson B 《Tropical animal health and production》2009,41(3):337-344

The aims of the current study were to illustrate figures for the characteristics of oestrous cycles especially on follicular dynamics, corpus luteum and changes in progesterone and prostaglandin F2alpha, in the Holstein cross-bred dairy heifers. Twenty six healthy and sexual-mature virgin heifers were monitored for signs of oestrus. Their ovaries were sonically examined and the numbers and the sizes of the follicles as well as of the corpus luteum were documented. In our study, no difference in ratio of the 2-wave and 3-wave patterned cycle was evident. Seasons' change did not affect on characteristics oestrous cycles as well as on dynamics of follicles and corpus luteum. The heifers showed high variation in manifesting oestrus especially on a number of hours. The ‘bodily’ oestrous signs lasted longer than did ‘behavioural’ signs and connection of lowering of the back to standing oestrus was established. Certain diversities comparing to of existed dairy breeds were drawn for follicular dynamics, corpus luteum and its progesterone: 1) the 1st an-ovulatory dominant follicles showed higher growth rate and earlier exceeded dominant diameter; 2) the follicle tended to quicker ovulate but with a smaller diameter at ovulation; 3) the corpus luteum exhibited 4−16.5 mm in diameter of central cavity. Connecting to the levels of progesterone, 4) the corpus luteum turned into active, as well as mid-luteal, period quite late, and 5) the duration of the active period of the corpus luteum was shorter, but 6) at the end of the cycle –around the day of oestrus, progesterone remained certain low but significant levels. In conclusion, the Holstein cross-bred dairy heifers in our study faced a problem of delayed post-ovulatory progesterone rise of which underlying causes are needed to be further scrutinised either at endocrine or at cell levels.  相似文献   

Host plant suitability,population dynamics and parasitoids of the horse chestnut leafminer Cameraria ohridella (Lepidoptera: Gracillariidae) in southern Sweden     

Birgitta Rämert  Marc Kenis  Elisabeth Kärnestam  Monica Nyström  Linda-Marie Rännbäck 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(5):480-486

Abstract

The spread of Cameraria ohridella in Sweden and population dynamics were monitored with pheromone traps during 2007–2009. The most northerly location where the moth was trapped and mines were observed was Uppsala (59°52′N, 17°38′E). The host plant range of C. ohridella and infestation levels of Aesculus spp. were assessed in southern Sweden. Aesculus hippocastanum and its varieties, A. turbinata and A.×hemiacantha were the most susceptible. No damage was observed on A.×carnea, A. parviflora and A. chinensis.

Studies of the parasitoid complex of C. ohridella revealed that the dominant parasite species was the braconid Colastes braconius, followed by the eulophids Minotetrastichus frontalis and Pnigalio agraules.  相似文献   

Growth patterns and plasma levels of testoterone, 11-ketotestosterone, and IGF-1 in male Atlantic halibut (Hippoglossus hippoglossus) from juvenile stages throughout sexual development     

Finn-Arne Weltzien  Ørjan Karlsen  Birgitta Norberg 《Fish physiology and biochemistry》2003,28(1-4):227-228

This study was initiated to establish basal data on growth patterns, as well as hormonal regulation of growth and maturation in male Atlantic halibut. Weight increase was approximately linear until one year before first sexual maturation, when growth rates decreased. In spawning fish, somatic growth was arrested or slightly negative. Plasma androgen levels reflected sexual maturation. A slight elevation of androgen levels was apparent one year before first maturation. Plasma IGF-1 levels fluctuated throughout the study and were correlated with body weight during the winter/spring of 1995, 1996, and 1997.  相似文献   

Growth, feed conversion efficiency and growth heterogeneity in Atlantic halibut (Hippoglossus hippoglossus) reared at three different photoperiods     

Albert K Imsland  Atle Foss  Sigurd O Stefansson  Ian Mayer  Birgitta Norberg  Bjørn Roth  & Mads D Jenssen 《Aquaculture Research》2006,37(11):1099-1106

Juvenile Atlantic halibut, Hippoglossus hippoglossus (initial weight (SD) 191.3 (±44.7)) g, were reared for 99 days at a constant temperature of 11°C and subjected to three different light regimes from 13 September to 21 December: continuous light (LD24:0), simulated natural photoperiod of Bergen (60°25′N, LDN) and constant 20 h light:4 h dark (LD20:4). The fish reared on the different photoperiod regimes differed in their growth patterns as juveniles exposed to long days, i.e. LD20:4 and LD24:0, exhibited faster growth than those experiencing a natural photoperiod. The LD20:4 group showed the highest average specific growth rate (0.72% body weight day^?1), whereas fish on LDN displayed the lowest average specific growth rate (0.60% body weight day^?1). The final mean weights of the LD20:4 and the LD24:0 groups were 15% and 12% higher than those of the LDN group. Dividing the duration of the experiment into three time periods shows that the LD20:4 and LD24:0 had a higher feed conversion efficiency (FCE) as compared with the LDN group during the first and the last period, while a reversed situation was observed in the second period. Our data indicate a larger variation in growth rates among individuals in the best‐performing groups (here LD20:4 and LD24:0). This may indicate that formation of size hierarchies is more pronounced in groups with more homogenous growth (here LDN). Overall, our findings indicate that extended light regimes result in faster growth and better feed conversion in juvenile Atlantic halibut. In line with findings on other flatfish species, this supports the concept that constant long day:short night or continuous light regimes should be used by the farmer in order to maximize growth and improve feed conversion in Atlantic halibut.  相似文献   

Performance of dairy cows fed an entirely organic diet containing cold-pressed rapeseed cake     

Birgitta Johansson  Elisabet Nadeau 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(3-4):128-136

Abstract

Organic dairy production will be based entirely on organically grown feeds as of 2008, and thereby a demand is created to find suitable feeds that are possible to grow locally. The aim of this experiment was to investigate whether milk yield and milk composition were maintained when cows were fed a 100% organic diet, with around 15% of dietary DM from cold-pressed organic rapeseed cake, compared to a 95% organic diet, in which a conventional protein source was used. Two experimental groups included 20 cows each and the study was carried out during two indoor periods. For cows fed the rapeseed cake diet, milk yield increased by 3.0 kg/day, but contents of milk fat and milk protein of multiparous cows decreased, resulting in similar yields of energy-corrected milk in early lactation. Milk from cows fed rapeseed cake had increased content of unsaturated fatty acids, including conjugated linoleic acid. In conclusion, it is possible to maintain milk production of dairy cows fed 100% organic feedstuffs using cold-pressed rapeseed cake as the main protein source compared to a 95% organic ration.  相似文献   

Genetic parameters for birth weight,growth, and litter size in Nordic sheep breeds     

Elise Norberg  Peer Berg  Jørn Pedersen 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(4):123-127

Abstract

In this study, genetic parameters were estimated for the Danish populations of Danish Marsk, Finnish Landrace, Gotland Pelt and Spel for birth weight (BW), average daily gain until two months (DG2) and litter size (LS). A multivariate animal model was used for estimation of genetic parameters, including fixed effects, both direct and maternal additive genetic effects, common litter effects and permanent environmental effects. Mean birth weight and DG2 ranged from, respectively, 3.39 kg and 262 g to 4.61kg and 286 g. Litter size ranged from 1.60 to 2.07. Direct heritability for BW ranged from 0.12 to 0.24, and maternal heritability for BW was about 0.23 for all breeds. Direct heritability of DG2 ranged from 0.19 to 0.33. The heritability for LS was between 0.08 and 0.13. The significant genetic correlations between the direct and maternal effect on both BW and DG2 were negative. The genetic correlations between the growth traits and LS were not uniform.  相似文献   

Time-series models on somatic cell score improve detection of mastitis     

E. Norberg  I. R. Korsgaard  K. H. M. N. Sloth  P. L⊘vendahl 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(4):165-169

Abstract

In-line detection of mastitis using frequent milk sampling was studied in 241 cows in a Danish research herd. Somatic cell scores obtained at a daily basis were analyzed using a mixture of four time-series models. Probabilities were assigned to each model for the observations to belong to a normal “steady-state” development, change in “level”, change of “slope” or “outlier”. Mastitis was indicated from the sum of probabilities for the “level” and “slope” models. Time-series models were based on the Kalman filter. Reference data was obtained from veterinary assessment of health status combined with bacteriological findings. At a sensitivity of 90% the corresponding specificity was 68%, which increased to 83% using a one-step back smoothing. It is concluded that mixture models based on Kalman filters are efficient in handling in-line sensor data for detection of mastitis and may be useful for similar applications to decision support systems.  相似文献