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Electrolytic balance:
normally this is measured as mEq/kg of feed. The formula most often used is (Na/23+K/39-Cl/35,5)*1000. The bibliography on pigs is not very abundant, but on milk cows there exists a large amount of publications due to their connection with post partum hypocalcaemia. The level that is normally recommended is 250-300 mEq/kg, although some authors have suggested higher values because of the positive effect on feed consumption, a highly important factor in post partum sows that will affect the rest of their reproductive life. However, recently, DeRouchey and cols. in 2000 and 2003, Roux ML in 2008 and Marco E 2009 show a possible interest in recommending lower levels because of the effect it would have on reducing the piglet mortality rate and on urinary pH, reducing the bacteria count in urine and therefore, the number of infections, as well as improving the number of live piglet births in future farrowings.Micotoxins
should be of special concern in peripartum. The use of mainly white cereals and wheat by-products especially predisposes problems related to the micotoxins. It isn’t uncommon to face problems such as a lack of uniformity in the litter, weight loss, increased still births, etc Therefore the productive parameters of the litter are reduced and pre-weaning mortality increases. Feed supplementation with micotoxin absorbents on many occasions can improve the litter situation and even the sow herself. It goes without saying that a systematic supplementation of feed is recommended, a detail that one should never lose sight of.Ante partum feed levels
have been linked to problems like constipation, MMA syndrome, lactating piglet mortality, etc… and later on low post partum feed consumption. Based on the evolution of porcine genetics over the last years, as well as practical observations on farms, and works such as that of Quiniou N and cols. in 2001 and Shelton NW in 2009, one can deduce that a lower, prolonged feed rate produces more problems than relatively higher rates, and that, in the case of high rates, they should be decreased before farrowing in order to avoid excessive fat at that time. A high feed rate doesn’t seem to have an effect on the average birth weight of newborn piglets, indicating, according to Quiniou, a much easier farrowing, although with no other advantages. Shelton NW found an increase in litter size among gilts, after their second farrowing, as an advantage. Practical advice would be to maintain an adequate body condition and lower the amount of feed dramatically only in the 2 or 3 days before farrowing. Post partum, the recommendation is to increase the daily feed rate as fast as possible until reaching the maximum quantity (at this point, management is very important).Nowadays no one will refute that the concept of crude fiber isn’t just as important as the materials from which it is derived, and therefore, the level of neutral fiber is commonly mentioned, and it goes without saying that the daily recommended consumption is from 350-400 g per sow, per day (Reese E and Douane 1997). With these formulations one has to assure that feed rejection doesn’t occur due to the content of some anti-nutritive factor in the fibrous raw materials. Therefore, the careful selection of these materials will be very important in tailoring these diets. In the Catalan raw materials market, the use of wheat bran, soybean husks, and beet pulp (which Fedna 2003 gave values of 35, 57 and 45 % neutral fiber) are frequently used. Either way it is very important to have available the appropriate analytics of these materials given that there exists a large variety of results for the values indicated.
