The feeding and health of suckler sows, piglets and fattening pigs are elements crucial to economic success in pork production: they also guarantee a premium quality product - pork meat - for the Swiss consumer. The project therefore focusses on the areas of meat quality (cf. aims 1 & 2), feed (cf. aims 1 & 3) and animal health (cf. aim 4), the object being to formulate the relevant technical production parameters and approaches to problems in pork production, and at the same time update the recommendations in the "Yellow Book".

Feeding of suckler sows during pregnancy
The majority of feeding recommendations for breeding sows in the Yellow Book are based on French studies. It is noticeable that these recommendations have turned out to be substantially higher by comparison with previous recommendations. Today it is generally acknowledged that feeding sows to body condition is the key to optimum reproductive performance, although there is doubt as to whether sows become too heavy under the new recommendations. Their implementation in the sty therefore still needs to be checked.

The prenatal development of embryos/foetuses depends on a great many factors, e.g. specific nutritional requirement in certain phases of pregnancy, uterus capacity, ovulation rate and placental efficiency. At the same time the number of live piglet births per sow per year has risen in recent years, thanks to breeding for increased fertility. On average this has meant a decrease in birth weight, but an increase in the spread of birth weight within a litter. Lower birth weight not only reduces the chance of piglet survival in the first days after birth and up to weaning, but also affects growth rate after weaning and during fattening as well as carcass and meat quality.

Meat quality
The recording of major meat quality parameters is both labour- and time-intensive, so methods like NIRS and e-nose are of interest, also with regard to quality control and the assessment of anticipated end product quality. Major meat quality parameters such as water binding capacity and tenderness are determined during conversion from muscle to meat. A better understanding of the complex proteolytic events in the first 24 h following slaughter is important so that specific measures (during fattening and during and after slaughter) can be formulated to influence them.

As part of the „ProSchwein" project it was shown that boar odour can be determined with great accuracy using the e-nose, but that this laboratory method needs to be adapted for industrial use. Subject to industrial partners showing an interest in the technology, ALP will pass on the know-how gained with regard to problems of boar odour and analytical procedures (HPLC method and sensor technology), and will help with the industrial implementation of this technology.

Feeding
In Switzerland the energy rating of feedstuffs is based on digestible energy. Some Swiss animal feed manufacturers with international parent companies are popularising an energy rating system based on nett energy, arguing that this is a more accurate rating system. However, a change in the energy rating system calls for closer examination, as the nett energy content of a great number of the feedstuffs used in Switzerland is unknown.

It is traditional to utilise by-products from the food industry for pigs. Over the next few years familiar by-products will increasingly be augmented by the market arrival of new ones, occasioned by the strenuous efforts currently being made by many countries to extract energy from renewable raw materials. Little is known about the nutrient levels, usage limits, toxicological safety and suitability for mother sows, piglets and fattening pigs of these by-products, which could be interesting as feed components for economic reasons.

From 2009 onwards the castration of male animals will only be possible if it is guaranteed painless. In addition to castration under anaesthetic, however, the fattening of young boars or immunocastrated pigs is also a possibility: according to informal reports from the EU this will very probably be the method of choice in future. Adjustments to the nutrient levels of fattening rations will be required in order to make full use of the anabolic potential of these animals. Switzerland also places great emphasis on the issue of the fat quality of the adipose tissue of slaughtered carcasses (fat index) and the issue of whether the PMI recommendation hitherto used will meet the requirements of these animals, known for their low fatty layer formation.

For capacity reasons Agroscope has not done any work in the area of farmyard manure for several years now. Under a joint venture agreement an external expert still supports Agroscope pending completion of the current revision of the Basic Principles of Manuring in Arable and Forage Cultivation (GRUDAF 2007/2008). As it will no longer be possible to continue this collaboration after 2007, Agroscope must take over the job from 2008 and has decided that coverage of this area will be divided between ART and ALP.

The concerns of the feedstuff industry (e.g. testing of feed additives) could not be taken into consideration during AP04/07. These resources will now be programmed into AP08/11 so that such short term research requests can be met within a justifiable framework.

Health
The mortality of newborn piglets in the first days of life and the morbidity rate in the first 2 weeks after weaning are high and partially cancel out breeding advances in the area of increased fertility. Especially for low-weight piglets from large litters there is an increased risk of receiving insufficient colostrum shortly after birth, of becoming weak and consequently being crushed by the sow. On working farms the digestive disorders frequently occurring after weaning, caused primarily by the abrupt switch from milk- to cereal-based nutrition, are prevented mostly by using antibiotics in the feed.

Reports from the field increasingly mention spontaneous bone breakage in fattening pigs. As a result doubt was thrown on the Yellow Book recommendations for Ca and P supply, but trials recently carried out by ALP have shown that the recommended Ca and P levels are adequate for optimum bone development. However, these trials have also shown that bone development can be impaired by the use of benzoic acid, and of "eco-feed" with reduced phosphorous content to minimise environmental pollution. The influence of organic acids on Ca and P metabolism and on bone mineralisation, particularly if used at the same time as P-reduced feed, needs to be examined more carefully. In addition, not much is known about the influence of reduced P supply during rearing on the bone stability of female pigs after reaching sexual maturity. This series of trials over several reproductive cycles will demonstrate the influence of reduced P supply during rearing on bone mineralisation and the incidence of lameness in breeding sows.