The daily nutrients required by pigs for maintenance, growth and reproduction depend on the size and physiological state of the pig.
During this stage the pig requires nutrients for maintenance and the growing fetus. Requirements during pregnancy are above the maintenance because nutrients are necessary for increased size and vascularity of the uterus as well as the mammary glands in preparation for lactation. Fat addition to pregnancy diets of pigs increases the blood glucose content of the piglets to be furrowed.
In addition to energy required by the sow for maintenance, energy is also required for milk production. The DE for maintenance for lactating sows is about 110 Kcal/kg live weight. Energy requirements for milk production are about 2000 Kcal per kg milk produced.
This is the period between birth and weaning of the piglet. Given that the new pig is immature in terms of digestive development it is hardly worthwhile to offer the new born a diet comprising cereals and other common ingredients until the period between 21 and 28 days.
Growers and finishers
This is the period between weaning and marketing of pigs. Finishing stage begins after 60kg live weight. During the growing phase pigs are fed a diet slightly higher in protein. Finishing stage requires less protein. In both stages diets can be offered based on cereals and plant proteins.
A diet for young piglets should include at leas 5% milk protein.
In Kenya there three types of feeds in the market.
Creep feed – usually in pellets. Should not be less than 18% protein content (CP). The feed is introduced to the sow 10 days before and after furrowing. Creep feed is also fed to piglets until weaning or until they are 20 kg live weight.
Sow and weaner – usually in mash form. This is normally for the breeding stock. Feeding depend on the finishing type of pig and can be fed either
- Adlib – fed up to 50 – 60 kg live weight for growers
- Restricted – fed at 1.2 to 1.5 kg feed 20 to 30 kg live weight
The advantage of feeding adlib is in low feed: gain ratio and therefore economical as compared to restricted feeding.
Finisher ration – fed to pigs of over 60 kg live weight. The ration is above 14% CP and is fed on a restricted basis. This is good because the pig will not put on too much fat.
If the feeding program is followed then the pigs will be marketed at 95 to 110 kg live weight usually within 200 days. This gives an average daily gain of 0.5 kg per day.Castrated boars are fed the same way.
Breeding gilts are fed on sow and weaner at 3kg per day until the time they about to be serviced. Then 14 days prior to service feed is increased by 0.5 kg per day. 14 days to the next estrus they are given 3.5 kg per day and after serving feeding revert back to 3.0 kg per day.
A common practice around furrowing time is to temporarily restrict feed intake in order to avoid overconsumption and problems related to constipation. Wheat bran is fed ¼ to ½ in the sow and weaner meal to increase the rate of passage. In the absence of wheat bran, maize bran, sawdust or any suitable filler material can be used. Sows appetite is depressed following parturition therefore feed restriction is warranted to avoid feed wastage.
Underfeeding of sows with substantial appetite shortly after furrowing should however be avoided. As a compromise feed the newly furrowed sow at least 2 times a day and offer an amount of feed that can be cleared within 20 minutes. Feed more frequently. Underfeeding shortly after furrowing will result in a decrease of milk production and consequently piglet losses.
Feeding during lactation
A sow’s performance during lactation is affected by her feeding program during the gestation period. Hence maximum yield during lactation is ensured by proper feeding.
Sows can adjust to inadequate energy and protein intake during lactation in the short term by utilizing body fat stores resulting in loss of body weight. A good feeding program during lactation should not result in sows in good condition during furrowing losing more than 10 kg. In practice lactating sows are given feed at 3kg + additional 0.25kg per piglet. In some places it is recommended at 2.5 + 0.4kg per piglet – this is a situation where feeds are of high quality.
Should problems be encountered with sows losing body condition because of poor appetite the following factors should be considered to improve feed intake.
- Feed intake during pregnancy – sows overfed during pregnancy usually have low feed intake during lactation
- Environmental temperature of furrow house – feed intake can be lowered by high temperatures. The ideal temperatures is 18 – 20oC
- Energy level of feed – if there is low intake then increase energy density of diet. This can be done by addition of tallow or sunflower oil at 6% of diet. Increase frequency of feeding to increase feed intake. Also instead of dry feeding, wet feeding will increase feed intake.
- Form of feed – pelleted diet increase feed intake.
Weaning to breeding
There is a relationship between body fat and reproductive fitness of sows. Slightly give the sow some additional feed according its condition after weaning. Weaning to breeding time is about 5 to 7 days.
Guidelines to evaluate sow feeding program
- Gilts weigh between 120 to 130 kg at first furrowing
- Gilts should not lose more than 10 kg in the first lactation
- Sows should have a net gain of 10 to 15 kg for each successive reproductive cycle. This happens up to 4th to 5th lactation.
- Live weight should stabilize at 160 to 170 kg
- Total feed requirements per sow per year should be about 1000kg
This follows the same scheme as for growing pigs until the boars are 60kg. After 60kg boars are fed on sow and weaner continuously – not pig finisher – until they are ready for service. Mature boars are given 2.5 kg feed per day. However depending on the condition of boar, ½ kg more or less feed is given.