Thomsson Ola, Magnusson Ulf, Bergqvist Ann-Sofi, Eliasson-Selling Lena, Sjunnesson Ylva Cecilia Björnsdotter
Division of Reproduction, Department of Clinical Sciences, Swedish University of Agricultural Sciences, SLU, P.O. Box 7054, 750 07, Uppsala, Sweden.
The Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning, P.O. Box 1206, 111 82, Stockholm, Sweden.
Acta Vet Scand. 2018 Feb 8;60(1):10. doi: 10.1186/s13028-018-0364-x.
Production systems with group housing of sows during a part of the lactation are used in certified organic production and can increase the occurrence of lactational estrus thus making batch-wise breeding difficult. The aim of this study was to investigate the occurrence of lactational estrus and time at return to estrus after weaning by following the performance of the sow (change in body weight, back fat and litter size) in three different management routines. The sows and their litters were moved from individual to multi-suckling pen at one (W1; n = 14), two (W2; n = 13), or 3 weeks (W3; n = 16) post farrowing. All sows had a total lactation of 6 weeks. Ovulation was monitored by analysis of fecal progesterone metabolites. Only one sow (W3) ovulated during lactation. Sows in the W2 and W3 groups had a shorter weaning-to-standing estrus interval than W1-sows (2.6 ± 0.3; 2.7 ± 0.2 and 4.0 ± 0.3 days respectively, P < 0.001). The W1-sows and piglets might have kept their nursing bond more intact all through the group housing since the piglets were completely dependent on the nursing at the time of their move to the group pen, thereby staying in lactational anestrus and retaining standard weaning-estrous interval. There was no difference in litter size at grouping or at weaning between management routines and parities. Third and later parity sows had significantly thicker back fat at farrowing and at weaning than 1st and 2nd parity sows (P < 0.05). In conclusion, the occurrence of lactational estrus can be low in a multi-suckling pen and the interval between farrowing and move to a multi-suckling pen can affect the weaning to estrus interval. The short weaning-to-standing estrus interval seen in W2 and W3 suggests that estrus detection should start immediately post weaning for sows kept in multi-suckling pens.
在认证有机生产中，采用在泌乳期部分时间将母猪群养的生产系统，这可能会增加泌乳期发情的发生率，从而使批次化配种变得困难。本研究的目的是通过跟踪母猪在三种不同管理程序下的表现（体重、背膘和窝仔数的变化），调查泌乳期发情的发生率以及断奶后发情恢复的时间。母猪及其仔猪在分娩后1周（W1组，n = 14）、2周（W2组，n = 13）或3周（W3组，n = 16）从个体哺乳栏转移到多仔猪哺乳栏。所有母猪的总泌乳期为6周。通过分析粪便孕酮代谢物监测排卵情况。只有1头母猪（W3组）在泌乳期排卵。W2组和W3组母猪的断奶至静立发情间隔比W1组母猪短（分别为2.6±0.3天、2.7±0.2天和4.0±0.3天，P<0.001）。W1组母猪和仔猪在整个群养期间可能保持了更完整的哺乳关系，因为仔猪在转移到群养栏时完全依赖哺乳，从而处于泌乳期乏情状态，并保持标准的断奶至发情间隔。不同管理程序和胎次之间，分组时或断奶时的窝仔数没有差异。第三胎及以后胎次的母猪在分娩时和断奶时的背膘显著厚于第一胎和第二胎母猪（P<0.05）。总之，在多仔猪哺乳栏中泌乳期发情的发生率可能较低，分娩至转移到多仔猪哺乳栏的间隔会影响断奶至发情间隔。W2组和W3组观察到的短断奶至静立发情间隔表明，对于群养在多仔猪哺乳栏中的母猪，应在断奶后立即开始发情鉴定。
