Effects of magnesium on the performance of sows and their piglets

The objective of this study was to evaluate the effects of supplemental magnesium （Mg） on the performance of gilts and parity 3 sows and their piglets. Fifty-six grits （Trial 1） and 56 sows （Trial 2） were assigned to one of 4 treatments according to their mating weight, respectively. The treatments comprised corn-soybean meal based gestation and lactation diets （0.21% magnesium） supplemented with 0, 0.015, 0.03, or 0.045% Mg from mating until weaning. The results showed that magnesium supplementation significantly （P 〈 0.05） reduced the weaning to estrus interval in both gilts and sows. There were significant effects （P 〈 0.05） of supplemental magnesium on the total number of piglets born, born alive and weaned in sows. In late gestation and lactation, the digestibility of crude fiber （quadratic effects, P 〈 0.05）, and crude protein （P 〈 0.05）, were significantly influenced by magnesium in gilts and sows, respectively. There were differences among the 4 groups in terms of the apparent digestibility of dry matter and crude fiber in sows （P 〈 0.0S） during both early and late gestation. The apparent digestibility of gross energy was increased for sows in late gestation （P 〈 0.05）, and lactation （quadratic effects, P 〈 0.0S）. At farrowing and weaning, serum prolactin levels and alkaline phosphate activities linearly increased in sows as the Mg supplementation increased （P 〈 0.0.5）. Serum Mg of sows at farrowing and serum urea nitrogen of sows at weaning was significantly influenced by Mg supplementation （P 〈 0.05）. The Mg concentration in sow colostrum and the serum of their piglets were increased by supplemental magnesium （P 〈 0.05）. In addition, growth hormone levels were linearly elevated （P 〈 0.05） in the serum of piglets suckling sows. Our data demonstrated that supplemental magnesium has the potential to improve the reproduction performance of sows, and the suitable supplemental dose ranged from 0.015% to 0.03%.

Prisoners' Dilemma Supergame on Rectangle Lattice

In this paper a class of large supergames, i.e., infinitely repeated games played by many players are studied. The players located on the vertex set of planar rectangle lattice play several basic games with his neighbors. The basic game is two-person prisoners’ dilemma game with asymmetric payoffs. Under the conditions of the pre-specified updating rules and the transition probabilities, the relevant stochastic process of strategy evolution forms a Markovian process. The simulation results about the long-run behavior are provided.

Management of re‐established artificial grasslands via grazing or fencing: Effects on plant and soil properties

Background:Revegetation is widely used in degraded grassland restoration.However,the responses of grassland plant and soil properties to fencing(FC)and grazing(GZ)remain poorly understood,especially the vegetation–soil coupling coordination(C_(d))mechanism.This study explored single and interactive responses of vegetation and soil properties under FC and GZ after revegetation.Methods:A field experiment with FC and GZ treatments was conducted in Loess Plateau reconstructed grassland,with degraded grassland as the control(CK).Plant and soil properties and C_(d) were analyzed using the analytic hierarchy process(AHP)and principal component analysis(PCA).Results:The order of soil comprehensive evaluation(SCE)was GZ>FC>CK,while that of vegetation comprehensive evaluation(VCE)was FC>GZ>CK.The C_(d) of CK was 0.39(mild imbalance),while the values of FC and GZ were 0.57 and 0.54,respectively(little coordination).The VCE/SCE of FC was 1.48(soil lag type),and the values of GZ and CK were 0.69 and 0.35,respectively(vegetation lag and vegetation loss type,respectively).Conclusions:Both GZ and FC improved C_(d) and facilitated recovery.However,degraded grasslands should be restored via moderate grazing for sustainable ecological and economic development.