Feeding modern sows

One of the main achievements in pig production over the past thirty years is the improvement in sow productivity, which is expressed in the number of pigs per sow per year, equal to approximately 16-22 piglets (Table 1).

Interestingly, this achievement was achieved not by increasing the number of live-born pigs in the litter, but more as a result of enriching the knowledge of feeding and rations, the care and maintenance of animals, through improved management strategies, and also by a better understanding of the need for protection Animal health.

A contributing factor was the reduction in the age of weaning. A deeper understanding of the physiology of feeding pigs allowed the use of certain strategies in various farming conditions, in which sows and boars are kept.

Table 1. Changes in sow productivity over the past 30 years *

Index	1970	1975	1980	1985	1990	1995	2001
Litter / sow / year (heads)	1,90	2,00	2,18	2,25	2,23	2,25	2,25
Liveborn piglets / litters (heads)	10,3	10,4	10,3	10,4	10,7	10,8	11,0
Grown pigs / sows / year (heads)	16,3	17,5	19,8	20,9	21,1	21,6	22,0
Annual removal of sows fr om production (%)	-	33,9	35,9	38,1	40,0	42,6	42,0
The exponent P2When measuring the thickness of spinal fat per 100 kg (mm)	-	22,0	19,0	14,5	13,0	11,5	11,0
Feed conversion rate for herd feeding (kg / kg)	3,80	3,40	2,90	2,80	2,70	2,58	2,61

* Data of the Commission for Meat and Livestock (MLC), United Kingdom

Compared with sows that were grown 30 years ago, modern sows became leaner, the fatty layer of the body decreased by as much as 50%, in accordance with the reduction in the thickness of spinal fat.

This not only altered the metabolic needs of the sow but also led to the fact that modern genotypes have become more sensitive to feed, Than their predecessors, who had ample reserves of the organism for the beginning of reproduction. These stocks helped the animal to protect against periods of extreme food shortages and periods when the need for nutrients exceeded their intake into the body

This situation has been worsened for the modern pig, since the selection of animals for the purpose of obtaining feed efficiency indicators when measuring feed costs for lean meat may have unintentionally led to animals with lower instinctive food intake.

Thus, the development of feeding strategies should pay attention to a whole cycle of animal productivity throughout life, and not just individual phases of reproduction.

Here are some of the changes in the characteristics of a modern sow:

1. The change in the composition of the body is leaner;
2. Larger body size of mature individuals;
3. Slopes to the early reproduction of the offspring to achieve a certain lean body mass;
4. Higher litter size and faster pig growth;
5. Higher milk yield;
6. The possibility of reducing appetite;
7. More differences in nutrient requirements;
8. Less flexibility in feeding strategies;
9. Animals are more susceptible to feeding, the environment and the means of managing the household.

The objectives and key points of the content of the modern breeding sow

Feeding and management strategies are the key points that ensure that a modern sow will reach its genetic potential for reproduction. In practice, the actual level of productivity is much lower than the ability of the animal, and in many farms, the norm is the business yield of piglets in the amount of 20-22 per sow per year, compared with the often indicated possibility of 30 piglets.

A more appropriate measure of reproductive capacity is also possible - by the number of pigs produced during the pig's entire lifespan, and not by the year. In this case, the target is 50-60 piglets. However, few sows reach this level, and 30-40 pigs in the life of the sow are the norm on many farms.

Production plans for achieving "good" and "excellent" productivity levels are proposed in Table 2. Approximately 10% of producers in many countries achieve "excellent" productivity levels, but why is the number of such farms still too small?

Table 2. Production plans for achieving the productivity of a modern sow

Index	Good	Excellent
Coefficient of repair guinea pigs (%)	40	35
Farrowing Ratio (%)	85	90
Amount of litters / sow / year	2,3	2,4
Blank days * / year	>35	L> 20
Farrowing	11,3	12,5
weaned piglets / litter	10,2	11,3
Grown piglets / sow / year	23,5	27,0
Piglet weanling weight ** (kg)	7,0	7,0
Litter weight of weaned pigs (kg)	71	77
Sows / piglet-wean feed (kg)	50	50
sow deliveries for all life	4	5

* A 7-day period was allowed from maturity to mating
** otluchennыe piglets from sows at age 23 days

An analysis of the results of several herd recording programs, such as the MLC in the UK (MLC, 1995-2002), suggests that the main difference between herds with low indicators and herds with high rates is The number of piglets born and born alive, as well as the number of farrowing pigs per year (Table 3).

Table 3. Size of litter in herds of different productivity

Index	Lowest level 1/3	Normal	Upper 1/3	The top 10%
Piglets
Total number of births	11,4	11,9	12,3	12,7
Born alive	10,5	11,0	11,4	11,8
Piglets-weaned	9,3	9,8	10,2	10,6
Sows
litter / sow / year	2,12	2,25	2,34	2,41
The piglets / sow / year	19,7	22,0	23,9	25,6
Unoccupied days	53	37	26	13

MLC 1995-2002, United Kingdom

It should be noted that the difference between the total number of born pigs and the number of weaned pigs was similar in all flocks, regardless of the level of productivity. On the basis of this, it can be assumed that in order to improve productivity, it is necessary to achieve an increase in ovulation and / or fertilization rates, a decrease in miscarriage, and also to know the factors that affect the above-mentioned indicators.

Similarly, to increase the number of farrowing per pig per year, it is necessary to shorten the period between weaning and mating and to reduce the number of pigs that return to sexual hunting. To improve performance and reduce potential losses, it is important to understand how the various components of the litter size affect reproductive performance and identify the main factors that affect them.

Scheme 1In general, demonstrates the importance of feeding and management strategies. If it is necessary to develop appropriate feeding and management strategies to optimize productivity, it is important to establish the required values for both body weight and the body parameters of young guinea pigs and sows at both the different stages of each parity and in general.

Table 4. Estimated body weight norms for mating

Parity	Body weight at mating time (kg)	Change in live (clean) body weight (kg)		R2For the period of mating (mm)	The change in P2(Mm)
		Durability	Lactation / after weaning		Durability	Lactation / after weaning
1	140	50	-15	20	+4	-2
2	175	10	-15	22	+3	-2
3	200	30	-10	23	+3	-2
4	220	25	-10	24	+2	-2
5	235	20	-10	24	+2	-2
6	245	15	-10	24	+2	-2

Recommended weight norms

The suggested values are shown in Table 4. The overall goal should be to achieve a constant body weight of 230-250 kg and a P2 value of the thickness of the spinal fat of approximately 24 mm for each pairing, starting at 5 parity and further.

Contents of young guinea pigs

The parameters of the young guinea pig's body during the first mating have a significant effect on pig productivity throughout life. Animals that have inadequate body parameters, when they are first selected and introduced into the farm, are usually unable to reach the desired number of parties.

The better the characteristics of the pig, the better the lifetime performance of the animal. Therefore, the mumps should be mature enough, have appropriate body parameters and sufficient reserves of lean meat and fat in the body.

The latter requirements are necessary not only for the reproductive processes to begin to work directly (in themselves), but also to act as a storage of nutrients during periods of nutritional discrepancy when metabolic needs exceed the intake of animal nutrients into the body.

In addition, the body's internal stores are also needed to protect the animal in poor environmental conditions. Thus, the young mumps should be of a certain age, size, maturity and must reach certain characteristics of the body at the first mating:

• 220-230 days - age;
• 130-140 kg - body weight;
• 16-20 mm P₂In measuring the thickness of spinal fat;
• Mating on the 2nd or 3rd day of sexual hunting.

To achieve these standards it is assumed that the breeding pig should be selected with a body weight of 60 kg and a special diet and feeding regime for the growing mumps should be developed, as shown in Table 5.

The best practical strategy for maximizing ovulation and fetal preservation is to provide intensive feeding during the sexual hunt before mating, followed by a period of mild feeding during the first 21 days after mating.

Table 5. The phase mode of feeding of guinea pigs

Phase	Body weight (kg) *	Age (days)	The thickness of the spinal fat (P2, Mm)	Metabolic energy (ME MKal)	Lysine (d)	Feeding strategy (kg / day)
				Per kg of ration
Phase 1	25 - 60	60 - 100	-7	3,25	12,0	at one's discretion
Phase 2	60 - 125	100 - 210	7 - 16	3,10	8,0	2,5 - 3,5
Phase 3	125 - 140	210 - 230	16 - 18	3,10	8,0	at one's discretion
Phase 4	Early pregnancy	230 - 260	-	3,10	8,0	2,0

* These are the expected norms. Body weight and the thickness of spinal fat may vary slightly depending on the genotype and the environment

The diet for the mumps should not only contain the right level of energy and amino acids, but must be enriched with certain minerals and vitamins to stimulate reproductive efficiency and provide strong bones and legs, which is necessary for a long tribal life. Selective rejection due to problems with the legs of the animal is a frequent occurrence in many farms.

Feeding during pregnancy and lactation

To develop a strategy for feeding and management, it is necessary to actively apply knowledge of the nutritional needs of animals at all stages of the reproductive cycle actively. Tables 6 and 7 show the requirements for energy and lysine content for the sow during gestation and lactation.

Table 6. Energy and lysine demand for sows during gestation

Body weight at mating time (kg)	Increase in net weight * (kg)	Energy (Meal ME per day)	Lysine (g / day)	Feed (kg / day)
120	45	6,8	15,8	2,25
150	35	7,2	13,8	2,40
200	25	7,6	12,0	2,55
250	15	8,0	10,5	2,70
300	10	8,7	10,0	2,90

* Except for the increase in the pregnant uterus and mammary glands. The feed contains 3.0 megacalorie ME / kg

Table 7. Energy and lysine demand for sows during lactation

Body weight after farrowing (kg)	Energy (MKal ME per day)		Lysine (g / day)		Feed (kg / day)
	10 piglets	12 piglets	10 piglets	12 piglets	10 piglets	12 piglets
150	18,8	21,6	49,0	58,0	5,8	6,6
200	20,0	22,8	50,0	59,0	6,2	7,0
250	21,0	23,8	51,0	60,0	6,5	7,3
300	22,1	25,0	52,0	61,5	6,8	7,7

The feed contains 3.25 megacalories ME / kg

Based on this knowledge, it is possible to develop feeding diets and introduce those feeding strategies that take into account the individual needs of the animal at each stage of its reproductive cycle and in each type of productive system.

This is especially important for a modern prolific sow, when the goal should be to achieve the required characteristics of the body throughout the entire reproductive life of the animal. During gestation, the main goal should be to feed the sows with high-quality diets for pregnant sows to achieve certain body weight and increase the thickness of the spinal fat (Table 4), and to achieve body parameters of 3.5 at birth (scale 1-5).

These values change with parity, and consequently the nutritional needs also change, as shown in Table 6. Requirements increase with the course of pregnancy, especially in the last trimester, when the nutrient requirements of a fast growing fetus are high. It is demonstrated in Figure 1 relative to the guinea pigs during their first pregnancy.

Consequently, it is important to increase feed intake during this period to ensure high fetal growth rates to maintain good sow body parameters and to promote the proper development of the mammary glands that are integral to the formation of colostrum and milk.

Scheme 1. The need for feed during gestation (parity 1)

During lactation, the goal is to get at least 10 piglets with a good body weight with minimal weight loss and sow body characteristics.

Perhaps the suckling period is the most critical period in the life of a pig. The feeding strategies used during this period affect both the growth and development of the pigs up to the bottom, as well as the subsequent reproductive potential of the sow and the overall productivity.

During lactation it is important to meet the requirements for the production of milk by a sow, which increases from about 3-4 liters / day immediately after farrowing to 10-12 liters / day in the lactation peak. Indeed, the values presented in Table 7 are average values for the entire lactation period, and they do not reflect the growing needs of the sow in nutrients as piglets grow and milk yields increase.

Feed intake should increase gradually during the first 4-5 days of lactation until the sow begins to consume 4-5 kg per day, after which it must be fed as needed (instinctive food intake) (Scheme 2).

A good idea is to compile a feeding ration scale for lactating sows of different parties and litter sizes and have such a scale at hand for each sow in the farrowing room.

Scheme 2. The need for feed during lactation

To achieve the necessary indexes of food intake during lactation, it is important to use high-quality diets and fully informed feeding strategies. It may be necessary to feed several times a day, since a sow that receives food only twice a day may not be able to consume the necessary nutrients to meet metabolic requirements, especially during late lactation.

Practical tips for increasing the appetite of an animal:

1. Feed a mouth-watering, nutritious food;
2. Feed a well-balanced diet of the appropriate nutritional specification (characteristics);
3. Gradually increase the daily intake rate during the first week, then at your discretion;
4. Food should be fresh, uninhabited or uncontaminated. Feed several times a day or depending on your appetite (as required) Granulated food is better than loose;
5. Ensure free access to fresh water at any time (consider raw food);
6. If there is a drip feeder, the flow rate should be> 2 liters per minute;
7. 7. Avoid the sows’ high-temperature exposure (<20°C) and reduce the environmental influence stress;
8. Maintain good climate control in farrowing areas;
9. Do not overfeed during the period of gestation;
10. Feed well-soluble fibers in diets for pregnant sows;
11. Diets in the period of pregnancy and lactation should be different;
12. Provide enough room for feeding;
13. Improve digestibility of nutritional elements of the diet of feeding;
14. Provide extra food for piglets;
15. Ensure good health and sow conditions.

On the other hand, it is important not to overfeed during early lactation, as this can limit the instinctive intake of feed to animals during late lactation when the requirements are greater;  In addition, it can cause the MMA syndrome.

The main limitation to achieving a good appetite during lactation is a lack of water, and water should always be provided in appropriate quantities. If there are drip drinkers, then the flow rate should be at least 2 liters per minute.

Large sows that feed large litters may need 40-50 liters/day, especially under high-temperature conditions. Lack of water limits the intake of food by the sow, and the milk yield. Sows after weaning piglets should consume more food for a quick return to sexual hunting and get the largest possible litter size for the next survey. Reducing the number of expensive "empty", or unproductive, days will mean a greater number of farrowings per pig per year.

The nutrition strategy with 3, 5 rations is best suited to the changing nutritional and metabolic needs of the modern hyper-proliferated pig and this helps to guarantee the optimal performance of the pig and its offspring.

In this way, The following characteristics of rations:

• Young pig: 3.1 megacalories ME (metabolic energy) and 8.0 g lysine/kg;
• Stability: 3.0 megacalories ME and 5.56.0 g lysine / kg;
• Lactation (total period): 3.25 megacalories ME and 10 g lysine/kg;
• Lactation (mumps: low intake): 3.35 megacalories ME and 11 g lysine/kg;
• Lactation (mumps: high intake): 3.10 megacalories ME and 9 g lysine/kg.

Since the content of lysine in the diet is known, it is possible to calculate the content of other essential amino acids in accordance with the term "ideal protein". A simple practical feeding strategy that meets the requirements of the sow at all stages of pregnancy and lactation is shown in Scheme 3.

Scheme 3. Anticipated strategy for feeding a modern sow (par 1)

These feeding rates are applied to sows in parity 1; For more mature sows, feed intake in each subsequent pregnancy should be increased by 0.2 kg/day, depending on body parameters.

The role of feeding in preventing the deaths of piglets

The mortality of piglets during periods of pregnancy and lactation is too high on many farms. From a practical point of view, it is difficult to guess other ways to reduce fetal deaths than through feeding and management strategies.

Some cases of mortality of piglets before weaning are associated with the fact that sows choke piglets during sleep with their weight in the early lactation period and, thus, it is important to consider the design of the box for farrowing.

The diet of feeding during gestation should be of good quality. In addition, feeding levels should be established to ensure the parameters of the sow body to 3.5 (on a scale of 1 to 5). It also helps to ensure the corresponding average weight of newborn piglets over 1.35 kg.

Such pigs have significant body stocks and viability, which helps them avoid the probability of being squashed by the sow and thus piglets have a high chance of survival.

Nevertheless, in many farms, there are too many stillborn piglets or piglets dying during lactation on many farms. Their number increases with the age of the sow and, of course, affects the number of weaned pigs and, consequently, the overall productivity of the sows.

There is the evidence that vitamins and trace elements, especially organic microelements, can help reduce these losses. For example, supplying the diet with selenium yeast (yeast) instead of inorganic sodium selenite helps to increase sow muscle tone, thereby facilitating childbirth and decreasing the number of stillbirths. The content of selenium in milk also increases; This has a beneficial effect on the pig's immune system, as a result of which the mortality rate decreases before weaning, as does the weight of the piglet at the time of weaning.

Iron is another important microelement since piglets are born anemic and should receive additional iron after birth, usually in the form of injections. On the other hand, the addition of organic iron to the sow feeding diet during pregnancy and lactation increases the iron reserves of piglets, improving their sucking reflex. This leads to high consumption of colostrum and milk, and also stimulates the sow to produce milk. The mortality rate in the period before weaning of piglets from the sow is reduced, and the weight of weaners is increased.

Thus, providing the proper level and source of trace elements can help reduce losses.

Low milk yields of sows lead to an inadequate feeding of pigs and to an unsatisfactory state of the immune system: piglets become more susceptible to stress and diseases. It was found that the worse the health of the sow, the lower the feed intake and the milk yield and the worse the piglets' performance.

Thus, the dosage of the feed, which improves the appetite and health of the sow and contributes to the development of the immune system of the sow and its piglets, is very important. At a low appetite in a sow, especially at a high ambient temperature, it is important to provide additional feeding of pigs to ensure that during lactation they grow in accordance with the norms and reach the appropriate body weight at the time of weaning.

A source:biomedia.rf