Damm BI, Vestergaard KS, Schrøder-Petersen DL, Ladewig J
The Royal Veterinary and Agricultural University, Division of Ethology and Health, Groennegaardsvej 8, 1870 C, Frederiksberg, Denmark
Appl Anim Behav Sci. 2000 Sep 1;69(2):113-124. doi: 10.1016/s0168-1591(00)00122-2.
Sows farrowing in a semi-natural environment terminate nest building 1-7 h prior to parturition after having built a nest for which a variety of materials are used. No nest-building behaviour occurs during parturition and the sows remain lying in the nest throughout most of the farrowing. In contrast, many intensively housed sows are restless during farrowing. To investigate whether gilts housed indoors would use branches for nest building and whether access to branches would affect the termination of nest building and parturient behaviour, we studied gilts housed individually in pens designed to stimulate natural nest building. The control group (n=21) had unlimited access to straw and the experimental group (n=21) had unlimited access to straw and branches. During nest building all the gilts used straw and all the experimental gilts also used branches. In the experimental group the interval from termination of nest building to birth of the first piglet (BFP) was significantly longer than in the control group (132 versus 58 min, P=0.04). In the experimental group, nest-building behaviour was also performed by fewer individuals during the interval from BFP until 2 h after than in the control group (38% versus 71% of the gilts, P=0.03). Gilts that performed nest building during this interval carried out more postural changes (P<0.001) and spent less time in lateral recumbency (P=0.001) than gilts which did not perform nest building. On average, gilts that performed nest building behaviour after BFP (n=26) spent 54% of the first 2 h of parturition in lateral recumbency and carried out 16 postural changes. Gilts that did not perform nest building behaviour during this interval (n=16) spent 85% of the time in lateral recumbency and carried out five postural changes. In 10 gilts that were selected randomly from the experimental group nest building was studied in more detail. In these gilts nest building peaked between 17 and 6 h prepartum. There was no difference in amount of behaviour directed towards straw and amount of behaviour directed towards branches.The results indicate that the termination of nest building in sows is under environmental feedback control. When only straw was provided the nests did not have much of a lasting structure. However, when gilts had access to straw and branches more structured and functional nests could be built. These nests may have been more effective in reducing the motivation for nest building prior to the onset of parturition.
在半自然环境中产仔的母猪，在分娩前1 - 7小时会停止筑巢行为，此前它们已经用各种材料筑好了巢。分娩期间不会出现筑巢行为，母猪在大部分产仔过程中都一直躺在巢中。相比之下，许多集约化饲养的母猪在分娩时会躁动不安。为了研究室内饲养的后备母猪是否会使用树枝筑巢，以及获取树枝是否会影响筑巢行为的终止和分娩行为，我们对单独饲养在旨在刺激自然筑巢的围栏中的后备母猪进行了研究。对照组（n = 21）可以无限制地获取稻草，实验组（n = 21）可以无限制地获取稻草和树枝。在筑巢过程中，所有后备母猪都使用了稻草，所有实验组的后备母猪也使用了树枝。在实验组中，从筑巢行为终止到第一头仔猪出生（BFP）的间隔时间显著长于对照组（132分钟对58分钟，P = 0.04）。在实验组中，从BFP到产后2小时期间进行筑巢行为的个体数量也少于对照组（分别为38%和71%的后备母猪，P = 0.03）。在此期间进行筑巢行为的后备母猪比未进行筑巢行为的后备母猪有更多的姿势变化（P < 0.001），侧卧时间更少（P = 0.001）。平均而言，在BFP后进行筑巢行为的后备母猪（n = 26）在分娩的前2小时中有54%的时间侧卧，有16次姿势变化。在此期间未进行筑巢行为的后备母猪（n = 16）有85%的时间侧卧，有5次姿势变化。从实验组中随机选择10头后备母猪对其筑巢行为进行了更详细的研究。在这些后备母猪中，筑巢行为在产前17至6小时达到高峰。针对稻草的行为量和针对树枝的行为量没有差异。结果表明，母猪筑巢行为的终止受环境反馈控制。当只提供稻草时，巢穴没有太多持久的结构。然而，当后备母猪可以获取稻草和树枝时，可以建造更有结构且功能更强的巢穴。这些巢穴可能在分娩开始前更有效地降低了筑巢的动机。
