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[Objective] The present experiment aimed to investigate the difference of the reproductive performances of Saba and its hybrid sows with different dietary crude fiber levels. [Method] Pregnant sows of parity 2 to 6 of 180 Saba (SB), 90 Duroc x Saba (DS) and 90 Landrace x Saba (LS) were selected for experiment. The sows of the same breed or hybridized combination were randomly divided into 3 groups according to the initial conditions of the sow's family, parity and historical reproductive performance. During the pregnancy and lactation periods, the 3 groups sows were fed different diets with 3.5%, 6.5% and 9.5% crude fiber (CF) levels, respectively. The differences of 11 reproductive performance indexes among 3 groups were analyzed by least square model. [Result] When the dietary crude fiber levels increased from 3.5% to 6.5% and 9.5%, the farrowing progress (FP) of SB sows were significantly shortened by 15.97 min (P<0.05) and 26.64 min (P<0.05), the FP of DS sows were significantly shortened by 10.94 min (P<0.05) and 9.60 min (P<0.05), and the FP of LS sows were significantly shortened by 59. 36 min (P<0.05) and 24. 82 min (P<0.05), respectively. However, there was no significant difference between the sow FP with the dietary crude fiber levels of 6.5% and 9.5% (P>0.05). The litter weight at 21 days (LW21D) of piglets of SB sows significantly increased by 3.75 kg (P<0.05) and 4.49 kg (P<0.01); The number of piglets at 21 days of the DS sows significantly increased by 1. 16 (P<0.05) and 2.06 (P<0.05), LW21D increased by 6. 28 kg (P<0.05) and 15.30 kg (P<0.01), number weaned increased by 1. 12 and 1.88 (P<0.05), and litter weight at weaning (LWW) increased by 11.55 and 19.57 kg (P<0.05); The LW21D of LS sows significantly increased by 8.78 kg (P<0.05) and 10.64 kg (P<0.01), and LWW increased by 8.78 and 14.87 kg (P<0.05), respectively. [Conclusion] The results of the study indicated that the sows of SB, DS and LS had good resistances to crude feed. For different pig breeds (hybridized combinations), the high level of crude fiber diet could improve the nursing performance of DS and LS sows more than that of DS sows. The reproductive performance of SB, DS and LS sows was not reduced but improved when fed with a moderate high crude fiber diet. [ABSTRACT FROM AUTHOR]

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Southwest China Journal of Agricultural Sciences is the property of Editorial Department of Southwest China Journal of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Jiangsu University (Natural Science Edition) / Jiangsu Daxue Xuebao (Ziran Kexue Ban) is the property of Editorial Department of Journal of Jiangsu University (Natural Science Edition) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective]In order to optimize parity structure and mating time of pig population, the effects of parity and mating season on gestation length and litter performance were studied. [Method]A reproductive record of total 3278 parities in 2016-2017 years for American Large White Sows from breeding pig faom of Yunnan Huijia Breeding Company Limited was analyzed. [Result] The breeding season had significant effect on the total litter size, the number of live litters（P <0.05）. The total number born and number born alive of sows in spring were significantly higher than those in summer and autumn（P <0.05）. It had significant difference under different parities for the total number born number born alive number of stillbirths, gestation period and so on（P<0.05）. The litter performance of the 3rd-5th parities and the 7th parity was better than that of other parities. [Conclusion] The best reproductive performance of the American White Sows is the 3rd, 4th, 5th and 7th parities, and the mating performance of sows in spring is better than that in other seasons. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aiming at the thrust computation of half-rotating wing as a new power wing to be applied in bionic flying, a model of the half-rotating wing was proposed and the formulas to calculate the model parameter were derived. The two CFD models, wings with fixed wall and no wall, were established based on XFLOW with reasonable computed area and boundary condition of the flow field, turbulent flow model and complex motion of rigid wings. The numerical simulation was made using the same parameters and inputs in a experimental model of the half-rotating wing to obtain the flow field characteristic of the two CFD models and the wing's propulsion affected by Weis-Fogh effect. The computed thrust was compared with experimented thrust in same conditions in all of motion period of the wing. The results indicate that the wing lap and fling always act on the velocity distribution in the flow field around the wing with fixed wall so as to greatly increase the wing thrust. The computed thrust from the models presented above can demonstrate real change of the wing thrust. These provide important reference for the thrust estimation of different parameter models with fixed wall. [ABSTRACT FROM AUTHOR]