159 The effect of sire FEC EBV on parasitism and survivability in grazing Katahdin lambs

Selection for reduced fecal egg count (FEC) is an important management tool to combat anthelmintic resistance in worm populations. To understand consequences of selection for parasite resistance, a divergent mating scheme was established whereby Katahdin rams with high (HiFEC; n = 4) or low fecal egg count (LoFEC; n = 4) estimated breeding values (EBV) were randomly mated to ewes at the Southwest Virginia AREC. Mid-March born lambs (n = 199) were managed as one group until approximately 120 days of age (Weaning: June 4). Beginning at 45 days of age, BW and FAMACHA scores were collected weekly. Deworming occurred as necessary (FAMACHA ≥ 3) and fecal egg counts were taken biweekly. Statistical analysis was performed using SAS with fixed effects of sire EBV type. Fecal egg count was significantly higher in HiFEC-sired lambs one week prior to weaning (665 vs. 427 eggs/g, P < 0.05) and again at three (3398 vs. 2175 eggs/g, P < 0.01) and five (3596 vs. 2209 eggs/g, P < 0.01) weeks post-weaning. These FEC differences corresponded to differences in lamb weaning and post-weaning FEC EBV (43% vs. -43%, P < 0.05 and 82% vs. -66%, P < 0.01; respectively). Lambs sired by HiFEC-rams required more anthelmintic treatment than LoFEC-selected lambs (76% vs. 61%, P < 0.05). The weaning and post-weaning FEC EBV of HiFEC-sired lambs was greater in lambs that died than those that survived to 120 d (37% vs. 83%, P < 0.01 and 73% vs. 138%, P < 0.01; respectively); however, this phenomenon did not occur in LoFEC-sired lambs. Taken together, these data indicate that LoFEC-sired lambs have reduced parasite burden and are more likely to survive to weaning. Thus, sire selection for low FEC EBV can have indirect effects on lamb survival and general immunity.

Growth and scale improvement of Israeli carp (Cyprinus carpio) based on genetic breeding

Background: There is a need to recover the genetic diversity of Israeli carp by continuous inbreeding and develop genetics-based breeding for rapid growth, better body shape, and improved scales. However, there are no breeding studies on developing domestic Israeli carp since 1973. To develop an Israeli carp breed that grows fast and has improved body shape and scale using genetic breeding methods. Results: Four breeding groups were set. A mating scheme was developed considering the morphological analysis and genetic distance of broodstock. F1 was produced according to the mating scheme. The Korea × China group grew faster in 17 months. Total length in the China × Korea group was small, but body height was similar to that of the other groups, and the condition factor was the highest. Common Israeli carp in Korea reached 1.7 kg in 17 months, and improved Israeli carp reached to 2.2 kg. The scale scores of the F1 group were 1.98 (China × China), 2.68 (China × Korea), 2.36 (Korea × China) and 3.18 (Korea × Korea). The average number of scales crossing between China and Korea was 2.52 and broodstock group was 3.15. F1 showed lower scale score (0.63) than broodstock. Conclusions: The improved carp has better scales than parent group, which improved in weight and scales compared to common Israeli carp. The Israeli carp developed by the genetics-based breeding grew quicker and had improved fewer scales, which will be of great value for domestic Israeli aquaculture industry due to good marketability.

EFFECT OF GROUP MATING SCHEMES ON LAMB GROWTH PERFORMANCE

The study was aimed to determinate the effect of group mating scheme on lamb growth performance. Rams, representing different group mating scheme, were assigned to mate 60-80 ewes per a ram for a 45-day breeding period. In group mating scheme, each ram is placed in a separate pasture with a group of ewes gathered from participating herders involved in group breeding during mating season. The average birth, weaning and post weaning weight for lambs from the group mating of selected rams to selected ewes involved in the study were 4.4, 33.8 and 40 kg for male lambs and, 4.3, 29.8 and 35.7 kg for ewe lambs respectively. These figures indicate that progeny of that group mating scheme were 0.5 to 6.3 kg for male lambs and 0.6-5.5 kg for ewe lambs heavier than progeny of group mating of selected rams to randomly allocated ewes at different age of growth (P <0.05). Mean values of birth, weaning and post weaning weight of progeny for control group mating were lower (P < 0.05) than those of the progeny for all other groups of mating.

Crossability Studies among Twenty Accessions of Roselle (Hibiscus sabdariffa L.)

Increasing exploitation of roselle (Hibiscus sabdariffa L.) and its products require that commercial varieties with superior attributes are developed to replace landrace varieties and to meet the growing demand for commercial-scale cultivation of the crop. In this study, twenty landrace varieties of roselle collected from three geographical regions of Ghana were artificially crossed in a pairwise mating scheme. The aim was to obtain relevant information pertaining to fertility status and extent of crossability among the accessions to facilitate breeding of improved varieties. Attempts at hybridisation were made both between and among 6 accessions of Hibiscus sabdariffa var Altissima and 14 accessions of Hibiscus sabdariffa var Sabdariffa. Crosses between accessions of Hibiscus sabdariffa var Altissima and Hibiscus sabdariffa var Sabdariffa yielded no hybrids, suggestive of a crossability barrier between the two mating groups. All intra-varietal crosses involving accessions of Hibiscus sabdariffa var Altissima were successful regardless of direction of cross while only few of the crosses among those of Hibiscus sabdariffa var Sabdariffa produced successful hybrids. Also fertility estimates of members of Hibiscus sabdariffa var Altissima were significantly higher (30.00%-80.00%) compared to those of var Sabdariffa (0.00%-43.00%). This implies that complete pairwise design could be used for intra-varietal crosses involving accessions of Hibiscus sabdariffa var Altissima, whereas only a partial pairwise design is feasible for members of Hibiscus sabdariffa var Sabdariffa.

A New Adaptive Hungarian Mating Scheme in Genetic Algorithms

In genetic algorithms, selection or mating scheme is one of the important operations. In this paper, we suggest an adaptive mating scheme using previously suggested Hungarian mating schemes. Hungarian mating schemes consist of maximizing the sum of mating distances, minimizing the sum, and random matching. We propose an algorithm to elect one of these Hungarian mating schemes. Every mated pair of solutions has to vote for the next generation mating scheme. The distance between parents and the distance between parent and offspring are considered when they vote. Well-known combinatorial optimization problems, the traveling salesperson problem, and the graph bisection problem are used for the test bed of our method. Our adaptive strategy showed better results than not only pure and previous hybrid schemes but also existing distance-based mating schemes.