Adding lysine to a typical corn-soybean-type pig diet or to a diet that replaces part of the soybean meal with other meals can significantly increase livestock performance. Recently, many researchers have discovered that lysine, in addition to improving the performance of livestock and poultry, produces low-hazard animal feed, reduces livestock and poultry excrement pollution, reduces high-temperature stress, early weaned piglet stress, and improves livestock product quality. The aspect has a positive effect. This article discusses the role of lysine. The pig's requirement for lysine and the factors that affect the demand are elaborated.
1 The role of lysine
Lysine plays an important role in essential amino acids. In common feeds, lysine is the most deficient amino acid except soybean and its cake. The addition of lysine in the diet of corn-soybean meal or the replacement of part of soybean meal with other meals can significantly increase production performance and feed conversion. Xu Xiliang (1991) added 0.1% to 0.3% lysine and 0.5% lysine to the basic feed formulated with cotton kernel cake and bean cake as the main protein source. L% to 0.2% methionine, hog weight gains up to 734-755 grams, meat ratio 2.95-2.85:1, lean meat ratio 57.21% to 58.05%, respectively than those who did not increase 6.5%, 7.6% and l. 2%.
GOihl (1993) summarized a number of experimental data and concluded that increasing lysine in swine diets can reduce backfat thickness, increase eye area, and lean meat yield. This response is more pronounced in young sows and shows a linear response. Coffey (1996) concluded that reports from nine experimental stations in the United States pointed out that when lysine in pig diets was increased from 0.58% to 0.8% by adding lysine, the dormitories of gilts decreased by 9%, and lean meat Growth rate increased by 12%. Coffey believes that when adding high amounts of lysine, care should be taken to increase the level of metabolisable energy. It is best to add fat at the same time. Usually, the ratio of lysine to metabolizable energy is 10.46g/MJ for growing pigs. 8.379/MJ is appropriate.
The fattening pig trial conducted by Coma et al. (1990) added lysine from 0.15% to 0.45% in a diet with a protein content of 14%, and the average daily gain increased by 14.49% to 42.34%. At the same time, the nitrogen output was reduced by 31.78% to 38.46%. Kerr (1995) reported that adding 0.35% lysine, 0.16% threonine, and 0.07% tryptophan to the pig diet can reduce the dietary protein by 4 percent without affecting the growth rate. Nitrogen emissions and energy emissions decreased by 29.3% and 4.4%, respectively. In conclusion, the addition of lysine and other limiting amino acids to low protein diets can not only reduce environmental pollution, but also save protein resources and reduce feed costs.
Gatel (1992) reduced protein levels in wheat-barley-soybean meal diets. Simultaneous addition of lysine had no effect on the performance of growing-finishing pigs, and total nitrogen output was reduced. The total nitrogen output decreased by 13.85% in the growth period and 19.32% in the fattening period. The piglet trial conducted by Han et al. (1995) showed that the daily gain, feed conversion, and digestibility of the experimental and control groups were similar, but the nitrogen and phosphorus emissions were reduced (reduced by 17.7% and 20.9%, respectively). , while saving feed protein 2%.
Easter believes that reducing protein and supplementing lysine and other limiting amino acids can improve production performance under heat stress conditions. Kerr (1987) also reported that pigs fed diets supplemented with lysine with low protein diets have lower caloric output than normal protein levels under heat stress conditions because of the low liver protein feed levels of pig livers. The weight drops (about 8%), and the liver plays a major role in heat production (Koong et al., 1982). In addition, the addition of lysine balances the amino acids of the diet, improves the utilization of the entire amino acid, and reduces nitrogen excretion in the form of urea, thus alleviating the effects of high temperature stress. Excessive use of plant protein in the early weaned piglets causes diarrhea in the piglets. Lowering the protein of the early weaned pig diet (from 20% to 18% or 16%), adding lysine and other limiting amino acids, reduced the frequency of diarrhea in piglets from 9.9% to 5.2% and 4. 9% (Ding Fayuan et al., 1995). In addition, mouse or rat experiments have shown that lysine deficiency causes atrophy of the thymus and spleen in rats. Addition of lysine and threonine to the diet can increase thymus weight, and skin rejection to allogeneic transplants increases (Sidranshs) , 1972). Klasing et al. (1988) demonstrated that chickens fed diets with sufficient or insufficient lysine respond differently to immunostimulation. However, Cook (1991) found that in the absence of lysine, the resistance of chickens to Pasteurella multocida was not weakened, and the lack of lysine in the diet did not discriminate the ability of mice to infect Salmonella (Pretro, 1981). ).
2 The lysine requirement of pigs
2.1 The Needs of Weaned Piglets
Owen et al. (1995) reported that isolated early weaned piglets require lysine to account for 1.65% to 1.5% of the diet. 80%, in order to achieve maximum production performance, other amino acids must maintain a proper ratio with lysine. Pettigrew (1993) calculated from published studies that 26 grams of lysine are required to produce 1 kg per litter per day. It accounts for 5.8% and 5.3% of dietary protein; NRC (1998) recommended lysine requirement for piglets 1.35% (5 to 10kg) and 1. 15% (10 to 20 kg), which accounted for 5.7% and 5.5% of the total dietary protein, respectively; China's lean-type pig raising standard (1987) recommended that the lysine requirement for piglets is 1.0% (5 to 10 kg). And 0.75% (10 ~ 20kg), respectively, accounted for 4.5% and 4.1% of total dietary protein. Current domestic research shows that the requirement for lysine in 8 to 20kg piglets is 0.84% ​​to 1.2%, and the ratio to protein is 5.2% to 6.0% (Xu Zhenying, 1994).
2.2 Growing and Finishing Pigs
In addition to the higher standards in the United Kingdom, the recommended values ​​for lysine requirements for growing and finishing pigs are similar in other countries, with a growth period of approximately 0.7% and a finishing period of 0.6%. Peters (1995) studied the effect of adding lysine and tryptophan to the diet of growing pigs (20-35 kg). The results showed that lysine was 0.6% and tryptophan was 0.15%. Li Defa (1995) reported that the growth rate was best when the dietary lysine level of 65 kg finishing pigs was 0.6%. Lin Yingcai (1996) measured the requirement for digestible lysine in growing pigs (36-60 kg) and finishing pigs (60-90 kg) using a rectal anastomosis, which were 0.656% to 0.453%, respectively.
2.3 Breeding pigs
Reports of lysine requirement for sows vary widely, from 20g to 50g per day (Johnston, 1993). The main factors affecting change are lactation, sow weight, and litter size. Pettigrew (1995) believes that The lysine requirement of pigs should be predicted based on the weight gain of the pigs. The weight gain is 1kg. The sows will need 26g lysine and the weight gain will be 2kg, which will need more than 45.24g. If the daily gain is 2.5kg, the sow should be at least daily. 58.2 g of lysine are needed. Stahy (1995) reported that if the average weight gain of piglets is 2kg, sows should consume 51g of lysine per day to maintain homeostasis. NRC (1998) states that the level of dietary lysine in pregnant sows is 0.44% to 0.50%, that of nursing sows is 0.71% to 0.90%, and that of male sows is 0.60%.
2.4 Damage caused by lysine overdose
The study found that pigs fed a high-lysine diet had a greater likelihood of rectal prolapse than those (P=0.0006) fed a standard diet, which was 6.73 times higher. In addition, high lysine diets can lead to reduced feed intake.
3 Factors Affecting Lysine Requirements
3.1 Diet energy level
O'Grady (1978) believes that the concentration of energy in the diet affects the requirement of lysine. In low energy (13.6 MJ/kg DE) diets, lysine is added to increase the intake and weight gain. High-energy (1.6MJ/kg DE) diet supplemented with lysine reduced feed intake, but the daily gain did not change. Lawrence (1994) found that digestible diets containing 3 g of lysine per megacalorie had higher digestibility and more nitrogen retention. He believes that lysine needs to be increased under high energy conditions. Sun Suling (1994) reported that as the ratio of lysine to digestible energy in diets increases, the production performance of young sows increases linearly, and the ratio is 1.65 g/MJ DE.
3.2 Dietary Protein Levels
Lin et al. (1985) studied the effect of different crude protein levels on the lysine requirement. When the protein level was between 17.5% and 21.5%, the requirement for lysine was gradually increased and there was a correlation between the two. That is, for each 1% increase in crude protein, the requirement for lysine increased by 0. 04%. Yang Luliang (1994) reported that the ratio of lysine to protein should reach 4.5% to 5.0% in the actual production, and the ideal protein target is 6.5% to 6.8%.
3.3 Dietary Cellulose Level
Cellulose can be combined with amino acids to inhibit the digestion of amino acids, so diets with high dietary cellulose content should have higher amino acid levels. The results of Sauer (1980) showed that adding cellulose to finishing pig diets reduced lysine digestibility.
3.4 Other amino acid levels in the diet
The addition of threonine to the diet can eliminate the weight loss caused by lysine excess, and threonine overdose can increase the activity of lysine-ketoglutarate reductase, Williams et al. (1993) reported that threonine and Lai The benefits of growing pigs and finishing pigs are best when the proportion of amino acids is 0.64 and 0.65. According to Peter (199), 0.15% tryptophan and 0.6% lysine in diets containing growing pigs (20 to 35kg) can meet the low level of 11% protein. The daily gain of piglets was the best when the ratio of methionine to lysine was 27.5%. WIlliams (1995) found that the ratio of lysine to sulfur-containing amino acids has a significant effect on the immune system of pigs. The recommended ratio is 0.57:1.2.
It is generally believed that there is a clear antagonism between lysine and arginine, and Zhang Jinhui summed up a large number of reports and found that whether the lysine excess or the arginine excess in the diet, the piglets are not between the amino acids Balance phenomenon, not antagonism between lysine and arginine. The ratio of proline to lysine in high-producing sow diets can significantly affect piglet weight gain. In general, the levels of proline and lysine are 0.75% and 0.9%, respectively. It is lysine 83%, but Richert (1996) found that the ratio of proline to lysine in high-producing sow diets can be as high as 128%, so it is recommended that the optimal ratio of valine to lysine is 120%.
In summary, the demand for lysine in pigs is affected by many factors, and the standard recommended amount is the minimum requirement under suitable conditions. In actual production, the nutrient variation in feed ingredients and the biological potency of nutrients should be combined. The optimal addition of lysine was determined in the case of feed toxins and anti-nutritional factors, loss of nutrients during feed formulation and processing.
Torx Key Set,Torx Hex Key,Torx Hex Key Set,Torx Allen Key Set
henan horn tools co.,ltd. , https://www.nbhorntoolsltd.com