Relationships between resistance characteristics of honey bees (Apis mellifera) against Varroa mites (Varroa destructor)

Ectoparasitic mite, Varroa destructor, today is one of the main reasons for colony losses worldwide. This study deals with relationships between measurements of resistance characteristics and measurements of bee infestation. During the trial, 105 Apis mellifera carnica colonies were tested according to AGT (Arbeitsgemeinschaft Toleranzzucht) breeding program. Data of hygienic behavior and mite population growth development were obtained. Further, they were evaluated for the traits SMR (Suppressed Mite Reproduction), recapping behavior (REC) and brood infestation. Significant influences of hygienic behavior, SMR and REC on the mite infestation were considered. SMR and REC show relatively high coefficients of regression on mite infestation values. The results show, that SMR and REC might be suitable selection traits to decrease the mite population growth within the colonies

Developing an optimized breeding goal for Austrian maternal pig breeds using a participatory approach

Due to economic and animal welfare related issues, the Austrian pig breeding organisations revised their breeding programs. Members of breeding organisations, breeders and academic staff were involved in a participatory process from the beginning. In several meetings and workshops, 11 new fitness traits regarding maternal abilities and piglet vitality were gathered. Therefore, breeders were asked to propose important traits regarding the sow maternal ability as well as piglet vitality. Calm behaviour, milk performance and conformation were mentioned as the most important traits for the sow and suckling behaviour, high birth weight and growth rate for the piglet, respectively. Prior to routine trait recording, feasibility of trait recording was tested under practical conditions. Subsequently, breeders were trained to record the fitness traits on their farms. It has to be emphasized that farmers were highly motivated to record traits comprehensively due to their participation during the process of defining the revised breeding goals. This motivation was also reflected in good data quality

Schätzung von Populationsparametern für die Toleranz der Honigbiene (Apis mellifera carnica) gegenüber Varroa jacobsoni Oudemans

Estimation of population parameters for tolerance of the honey bee (Apis mellifera carnica) for Varroa jacobsoni Oudemans. The steady chemical treatment against V. jacobsoni mites shows some essential problems: residuals of the drugs in the bee products and resistance of the mites to the active agents in the drugs. A method to control varrooosis without chemical treatments must be found. The best way to avoid problems created by chemical treatments is through selection for a higher tolerance to V. jacobsoni by the honey bees. A basic requirement to achieve this aim is the knowledge of population parameters for the tolerance to the mite. Considering that the reproductive biology of the honey bee deviates from that of other livestock species, heritabilities were estimated for tolerance to V. jacobsoni and for honey yield. Data were sampled from a total of 1 638 performance-tested colonies reared from 412 queens in the years 1988-1995. The queens belonged to the Institute of Bee Research in Lunz am See, Austria and private beekeepers of the breeding union, Austrian Carnica Association. Traits recorded were honey yield and tolerance to V. jacobsoni. As a general selection criterion for tolerance, the number of mites were counted on a special bottom board during the annual treatment with Apistan at the end of the testing season. Population parameters were estimated by an adapted half-sib analysis based on queens, using the restricted maximum likelihood (REML) methodology. The average relationship between two randomly chosen females (queens) was estimated as 0.38. The estimated heritability for honey yield was 0.20, which is documented by several other studies. The estimated heritability for tolerance to V. jacobsoni was 0.13 (table II). The phenotypic correlation between honey yield and tolerance to V. jacobsoni indicated a positive tendency (+0.17). The genetic correlation (-0.05) showed a very weak favourable direction, but owing to the standard deviation (0.24) it has to be interpreted very carefully. Further studies are necessary to analyse the genetic correlation between honey yield and varroa tolerance precisely. According to the results, selection response for tolerance to V. jacobsoni can be expected if performance testing and selection is carried out in large breeding populations. © Inra/DIB/AGIB/Elsevier, Pari

Open Nucleus Cattle Breeding Programme in the Lake Victoria Crescent Region of Uganda

Abstract The availability and accessibility of livestock products, facilitated by efficient farm production, is highly recognized by Uganda as one of the major ways of alleviating poverty. Although animal genetic improvement offers one of the most powerful and cheapest means of improving the productivity of farm animals, its effective exploitation has been hampered by lack of well planned and executed breeding programmes. With the help of the open nucleus breeding strategy, recommended by many authors for developing countries (Bondoc et el., 1993

Heritabilities and genetic correlations for honey yield, gentleness, calmness and swarming behaviour in Austrian honey bees

Heritabilities and genetic correlations were estimated for honey yield and behavioural traits in Austrian honey bees using data on nearly 15,000 colonies of the bee breeders association Biene Österreich collected between 1995 and 2014. The statistical models used distinguished between the genetic effect of workers and that of the queen of the colony. Heritability estimates for worker effect were larger than those for queen effect. Genetic correlations between both effects were negative. Heritability estimates for the sum of both effects (i.e. selection criterion) were 0.27, 0.37, 0.38 and 0.06 for honey yield, gentleness, calmness and swarming behaviour, respectively, indicating that meaningful genetic improvement is possible. Genetic correlations between these traits were generally small to medium, with large standard errors, with the exception of the high genetic correlation between gentleness and calmness. The models we present here can be used to estimate breeding values in honey bees.</p

Physico-chemical characteristics of Apis dorsata, A. cerana and A. mellifera honey from Chitwan district, central Nepal

Honey samples from Apis dorsata, A. cerana and A. mellifera were collected by cutting a piece of honey comb directly from the colonies on the same day and from the same floristic region of Chitwan district, central Nepal. Physico-chemical analysis of the honey samples was performed. The values obtained for moisture content, electrical conductivity (EC), invertase, and proline content were significantly different between all the honey groups. The analytical values for Apis dorsata ($n=28$), A. cerana ($n=26$), and A. mellifera ($n=27$) respectively were: 21.5, 20.1 and 17.1 moisture content (g/100 g honey); 0.96, 0.65 and 0.31 EC (mS/cm), 373.4, 218.2 and 110.9 invertase (Siegenthaler U/kg), and 875.8, 323.0 and 610.2 proline (mg/kg). There were no significant differences between the honey types in pH, glucose oxidase, and the amount of glucose. However, the amount of fructose was significantly higher in A. dorsata and A. cerana than in A. mellifera honeys. Similarly, the amount of oligosaccharide L$_2$ was significantly higher and sucrose was significantly lower in A. dorsata honeys than in A. cerana and A. mellifera honeys.Caractéristiques physico-chimiques des miels d'Apis dorsata, d'Apis cerana et d'Apis mellifera du district de Chitwan, Népal. Quatre-vingt-un échantillons de miels provenant de 28 colonies d'Apis dorsata, 26 d'Apis cerana et 27 d'Apis mellifera ont été prélevés en découpant un petit morceau de rayon de miel directement dans chaque colonie, le même jour et dans la même région floristique du district de Chitwan dans le centre du Népal. Les échantillons ont été conservés dans les mêmes conditions et leur analyse physico-chimique effectuée (Tabs. II et III). La teneur en eau, le pH et la conductibilité électrique ont été déterminés selon les méthodes harmonisées de la Commission Européenne pour le Miel [CITE]. L'invertase, la proline et la glucose oxydase ont été respectivement mesurées selon les méthodes originales de Siegenthaler [CITE], Ough [CITE] et Shepartz et Subers [CITE]. Les spectres de sucres ont été analysés en chromatographie liquide haute pression d'après la norme DIB 10758 à l'Institut d'apiculture de Celle, Allemagne. Les résultats montrent que la teneur en eau, la conductibilité électrique, l'activité de l'invertase et la teneur en proline sont significativement plus élevées dans les miels provenant d'A. dorsata que dans ceux provenant d'A. cerana ou d'A. mellifera. Dans les miels d'A. cerana, la teneur en eau, la conductibilité électrique et l'activité de l'invertase sont significativement plus élevées que dans les miels d'A. mellifera, mais la teneur en proline est significativement plus faible. Le pH et la glucose oxydase ne présentent pas de différence significative entre les trois types de miel. Le fait que la conductibilité électrique et que l'activité de l'invertase soient plus élevées dans les miels d'A. dorsata et d'A. cerana pourrait être dû à la plus grande teneur en miellat de ces miels. Dans les miels d'A. dorsata il existe une corrélation positive entre la conductibilité électrique, l'invertase et la proline. Il existe aussi une très bonne corrélation entre la conductibilité électrique et l'oligosaccharide L$_2$. Ce sucre a été trouvé dans les échantillons de miel qui avaient une conductibilité électrique $>0,7$ mS/cm. Il pourrait donc être possible de déterminer si le miel est un miel de fleurs ou un miel de miellat en mesurant la conductibilité électrique et le sucre L$_2$. Le nourrissement au sucre n'est pas une pratique répandue dans le région étudiée ; la teneur en saccharose reste donc dans les limites des critères de qualité définis par la Commission Internationale du Miel (IHC) [CITE]

Correction to: Heritabilities and genetic correlations for honey yield, gentleness, calmness and swarming behaviour in Austrian honey bees

In the paper, we computed the phenotypic variances of traits ignoring that the worker effect is in fact the colony mean, which has consequences for the estimates of heritabilities.</p