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J. Stefanowska D. Swierstra A. C. Smits J. V. Van Den Berg J. H. M. Metz 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(2):57-64
Now that group housing is replacing individual crates, so that calves can lie, stand and walk on the pen floor, the quality of the floor for group-housed calves has become the focus of attention. The reaction of two groups of four calves to a double area of floor made from two materials (wooden slats and synthetic slats with a rubber coating) was examined round the clock for 5 days. The calves were switched between pens twice, and in each case the 5 day observation period was repeated. In all three phases all calves spent significantly more time ( P <0.01) lying on the wooden floor: on average 656 min day -1 compared with 294 min day -1 on the synthetic floor. The time spent in the standing/walking position on both floors, occurrence of slip incidents and self-maintenance behaviour did not differ significantly between floors. The observations on use of the pen floor for lying and for standing/walking in combination with feeding, plus observations on fouling of the floors with excreta suggest that future pen design could be functionally divided into lying and walking/eating areas. 相似文献
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Fan Liu Casie J Braden Robert J Smits Jessica R Craig David J Henman Chris J Brewster Rebecca S Morrison Rebecca Z Athorn Brian J Leury Weicheng Zhao Jeremy J Cottrell Frank R Dunshea Alan W Bell 《Journal of animal science》2021,99(9)
Sows mated in summer produce a greater proportion of born-light piglets (<1.1 kg) which contributes to increased carcass fatness in the progeny population. The reasons for the low birth weight of these piglets remain unclear, and there have been few successful mitigation strategies identified. We hypothesized that: 1) the low birth weight of progeny born to sows mated in summer may be associated with weight loss during the previous summer lactation; and 2) increasing early gestation feed allowance for the sows with high lactational weight loss in summer can help weight recovery and improve progeny birth weight. Sows were classified as having either low (av. 1%) or high (av. 7%) lactational weight loss in their summer lactation. All the sows with low lactational weight loss (LLStd) and half of the sows with high lactational weight loss received a standard gestation feeding regime (HLStd) (2.6 kg/d; day 0–30 gestation), whereas the rest of the sows with high lactational weight loss received a compensatory feed allowance (HLComp) (3.5 kg/d; day 0–30 gestation). A comparison of LLStd (n = 75) versus HLStd sows (n = 78) showed that this magnitude of weight loss over summer lactation did not affect the average piglet or litter birth weight, but such results may be influenced by the higher litter size (P = 0.030) observed in LLStd sows. A comparison of HLStd versus HLComp (n = 81) sows showed that the compensatory feeding increased (P = 0.021) weight gain of gestating sows by 6 kg, increased (P = 0.009) average piglet birth weight by 0.12 kg, tended to reduce (P = 0.054) the percentage of born-light piglets from 23.5% to 17.1% but reduced the litter size by 1.4 (P = 0.014). A subgroup of progeny stratified as born-light (0.8–1.1 kg) or -normal (1.3–1.7 kg) from each sow treatment were monitored for growth performance from weaning until 100 kg weight. The growth performance and carcass backfat of progeny were not affected by sow treatments. Born-light progeny had lower feed intake, lower growth rate, higher G:F, and higher carcass backfat than born-normal progeny (all P < 0.05). In summary, compensatory feeding from day 0 to 30 gestation in the sows with high weight loss during summer lactation reduced the percentage of born-light progeny at the cost of a lower litter size, which should improve growth rate and carcass leanness in the progeny population born to sows with high lactational weight loss. 相似文献
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