CN103202392B - Application of NCG (N-CarbamylGlutamate) and VC (Vitamin C) in preparing heat stress-resisting feed additives or feeds - Google Patents

Abstract

The invention provides application of NCG (N-CarbamylGlutamate) and VC (Vitamin C) in preparing heat stress-resisting feed additives or feeds. According to the invention, when the NCG and the VC are combined, the heat stress resisting ability of livestock (particularly sows) can be remarkably increased, so that the NCG and the VC produce a synergistic effect, can be widely popularized and applied in the field of animal husbandry and have good market effect and social effect.

Description

Application of NCG and VC in the preparation of anti-heat stress feed additive or feed

technical field

The invention relates to the field of livestock breeding, in particular to the application of NCG and VC in the preparation of anti-heat stress feed additive or feed.

Background technique

Feed additives refer to small or trace substances added during feed production, processing and use, which are used in small amounts but have significant effects in feed. Feed additives include nutritional additives, pharmaceutical additives, and some additives that promote digestion or metabolism, which have obvious effects on strengthening the nutritional value of basic feed, improving animal production performance, ensuring animal health, saving feed costs, and improving animal product quality. .

N-carbamylglutamate (N-Carbamylglutamate, NCG), the Chinese name is N-carbamylglutamate. In the past, NCG was mainly used in humans. On the one hand, as a nutritional enhancer, it can significantly increase muscle production (content), and it is added to products for bodybuilding to promote muscle growth; on the other hand, it is used as a drug to treat some rare human diseases : Such as neonatal hyperammonia caused by congenital N-acetylglutamate (NAG) synthetase deficiency and neonatal rare genetic disease - maple syrup urine disease (Kalkan et al., 2009).

Recent studies have shown that NCG can promote the endogenous synthesis of arginine. Arginine is a free radical scavenger in the body (Jiang Zhen et al., 2000). Arginine and molecular oxygen are catalyzed by nitric oxide synthase (NOS) to generate nitric oxide (NO). NO is a new type of cell information molecule, which has the functions of dilating blood vessels, inhibiting platelet aggregation, inhibiting cell proliferation, inhibiting lipid peroxidation and formation of glycation end products (Assumpcao et al., 2008). An appropriate amount of NO in animals can scavenge oxygen free radicals and play a role in anti-oxidative stress ((Beligni et al., 2002; Huang et al., 2009). Therefore, NCG can improve the litter production rate of multiple litter animals by promoting the endogenous synthesis of arginine. Number and birth weight, promote growth and development of juvenile animals.

Heat stress refers to the sum of non-specific physiological responses made by the body in high ambient temperature to any demands placed on the body by the thermal environment. Non-specific physiological reactions are mainly manifested as: accelerated respiratory movement, increased carbon dioxide excretion, respiratory alkalosis; heart failure, cerebral congestion, pulmonary edema, hypoxia, etc.; increased oxidative metabolism in the body, increased peroxides, and membrane system damage; substances Accelerated metabolism, decreased immunity; increased urination, increased ion loss. With global warming, heat stress has become one of the important factors that endanger livestock production. Animals, including pigs, often experience heat stress, which can easily cause the above reactions, leading to loss of appetite or even illness, which in turn affects growth. According to different research results, the addition of NCG to sow diets can indeed improve production performance, and it has been determined by research that the optimum amount of NCG added to sow diets should be 0.5kg/ton, and the optimum time to add NCG should be 0.5kg/ton. First month - weaning. However, as a commonly used feed additive, NCG has no literature reports on its ability to resist heat stress after being added to sow feed, and the effect of using it in conjunction with vitamin C.

Contents of the invention

The purpose of the invention is to overcome the defect of insufficient heat stress resistance ability of conventional feed, and provide the application of NCG and vitamin C in the preparation of heat stress resistance feed additive and feed.

The research of the present invention finds that although NCG and vitamin C alone have the effect of resisting heat stress to a certain extent, the degree of effect is limited and it is difficult to further improve it. increase, showing that the two have a synergistic effect. Based on this, the present invention provides the application of NCG and vitamin C in the preparation of anti-heat stress feed additive and feed.

For the above application, the preferred weight ratio of NCG and vitamin C is 1-2:1-2, more preferably 1:1. The content in the feed is preferably 0.05-0.15% (w/w), preferably 0.1% (w/w).

The above-mentioned feeds and feed additives are used to improve the heat stress resistance of domestic animals, including but not limited to pigs, especially sows.

The above-mentioned feed additives can be directly added to the diet of livestock, or can be added simultaneously with other feed additives, but attention should be paid to the combination ratio of various components when adding.

The above-mentioned feed additives should be added during the period from before production to weaning of young animals, so as to maximize the benefit and input ratio. For example, sows should be supplemented with the feed additive of the present invention from one month before delivery to weaning.

The N-carbamoylglutamic acid in the present invention is an analog of N-acetylglutamic acid (NAG), which can function like NAG in animals and participate in the urea cycle of the body, has a long half-life, stable metabolism, and has a wide range of biological learning function. Studies have shown that NCG can act as a metabolic activator to participate in the activation of dihydropyrrole-5-carboxylate synthase (P5CS) and carbamoyl phosphate synthase I (CPS-I), and promote the synthesis of citrulline from glutamine or proline acid, which in turn promotes the synthesis of arginine (Arg) (Wu et al., 2004), so it is called arginine endogenous activator. As a NAG analogue, NCG maintains the body's arginine at a relatively high physiological level, and after a series of metabolic processes, it can be converted into substances with important biological activities, mainly nitric oxide (NO) and polyamines (including putrefaction amines, spermidine and spermine). It can be seen from the above that the anti-oxidative stress effect of arginine in vivo is mainly realized through the NO pathway.

As a water-soluble free radical scavenger, vitamin C in the present invention participates in more reactions than vitamin E, a fat-soluble free radical scavenger. It can be seen that the mechanism of vitamin C to scavenge free radicals is also richer than vitamin E, and vitamin C, in addition to directly exerting In addition to the function of scavenging free radicals, it can also assist vitamin E and glutathione to scavenge free radicals. In the Pig Feeding Standard (NY/T65-2004), there is no clear requirement on the content of vitamin C in sow feed. In recent years, vitamin C has been widely used in improving pig fecundity, heat stress resistance, and preventing infectious diseases, poisoning and metabolic diseases, and has achieved remarkable results (Xing Dianquan, 2012).

In the present invention, adding NCG and vitamin C to the sow feed can reduce the respiratory rate and body temperature of the sow under high temperature conditions, reduce the content of malondialdehyde and cortisol in the blood, and increase the immunoglobulin G and heat shock protein 70 in the blood content, especially in significantly reducing the content of malondialdehyde and cortisol in the blood, reducing the generation of free radicals in the body, and reducing the heat stress caused by high temperature to sows. And the research of the present invention shows that only using NCG or vitamin C alone to improve the heat stress resistance ability of domestic animals is very limited, but after the two are combined, its heat stress resistance ability is significantly improved, indicating that both NCG and vitamin C have produced synergy.

Detailed ways

The following examples are used to further illustrate the present invention, but should not be construed as limiting the present invention. On the premise of not departing from the spirit and essence of the present invention, any modifications or replacements made to the present invention belong to the scope of the present invention.

Example 1

1. Materials

1.1 Additives N-carbamoylglutamic acid (purity ≥ 97%), vitamin C (purity ≥ 99%)

1.2 Large white sows of animal law system (a large breeding pig farm in Beijing)

2. Methods and Results

2.1 Experimental design

The sow experiment was carried out from July to August 2012. During the experiment, the average temperature was 25.8 degrees, and the average daily maximum temperature was 30.2 degrees. The number of days with the daily maximum temperature higher than 30 degrees Celsius was 47 days; the average humidity was 58.5%.

In the sow feeding experiment, 120 French Large White sows of the same age and parity were selected and randomly divided into 6 groups, 20 in each group. Each group randomly received one of the treatments in Table 1 during the prenatal January-weaning period, and the amount of additives used in each group is shown in Table 1. After 3 days of using the additive, start to record the daily feed intake, measure the respiratory rate and body temperature of the participating pigs at 14:00 every day, and record the litter size, live piglet number, and newborn litter weight of each group after delivery. Record the number of weaned live piglets and weaned litter weight, calculate the average respiratory rate, body temperature, average newborn individual body weight and average individual body weight after weaning, collect anterior vena cava blood on the morning of the sow's farrowing day, and measure malondialdehyde (MDA) after separating the serum , immunoglobulin G (IgG), cortisol (Cor), heat shock protein 70 (HSP70) content.

Table 1 Experimental design

2.2 Test results

Addition of different additives from 1 month before farrowing to weaning had an effect on respiratory rate, body temperature and feed intake of sows (Table 2). It can be seen from Table 2 that the addition of NCG, vitamin C or a combination of NCG and vitamin C to the feed of sows from January to weaning before delivery can reduce the respiratory rate and body temperature of sows, and improve the feed intake of sows under heat stress weather conditions amount, especially in group C.

Table 2 Effects of different additives on respiratory rate, body temperature and feed intake of sows

Note: Different lowercase letters in the same column indicate significant differences (p<0.05).

Addition of different additives from 1 month before farrowing to weaning had an effect on sow performance (Table 3). It can be seen from Table 3 that the production performance of sows supplemented with NCG, vitamin C, or the composition of NCG and vitamin C in the feed during the prepartum 1 month to weaning period is better than that of the control group, and the effect of the C group is the most obvious, mainly in the weaning period. The maximum number of weaned live piglets and average individual weight can be obtained at this time.

Table 3 Effects of different additives on sow performance

Note: Different lowercase letters in the same column indicate significant differences (p<0.05), and different uppercase letters in the same column indicate extremely significant differences (p<0.01).

Adding different additives during prepartum 1 month to weaning had an impact on the stress resistance of sows (Table 4). It can be seen from Table 4 that the anti-stress ability of sows supplemented with NCG, vitamin C or the composition of NCG and vitamin C in the diet from January before delivery to weaning period was improved compared with the control group, and the effect was most obvious in group C, mainly It is manifested in reducing the content of malondialdehyde and cortisol in the blood, increasing the content of immunoglobulin G and heat shock protein 70 in the blood, especially in significantly reducing the content of malondialdehyde and cortisol in the blood, reducing The generation of free radicals in the body reduces the heat stress of high temperature on sows.

Table 4 Effects of different additives on sows' anti-stress ability

Note: Different lowercase letters in the same column indicate significant differences (p<0.05), and different uppercase letters in the same column indicate extremely significant differences (p<0.01).

Claims (3)

1.NCG and vitamin C are in the application of preparing in anti-heat stress feed additive or feed, and described NCG and ascorbic weight ratio are 1:1.

2. application according to claim 1, is characterized in that, described NCG and the vitamin C content in feed is 0.05～0.15% (w/w).

3. application according to claim 2, is characterized in that, described NCG and the vitamin C content in feed is 0.1% (w/w).