Dihydropyridines

Molecular formula:C₁₃H₁₉NO₄

Chemical name:2,6-dimethyl-3,5-diethoxycarbonyl-1,4- Dihydropyridines

Appearance: light yellow crystalline powder , odorless.

Molecular weight:253.30

Structural formula:

·Dosage:g/ton:

·Cautions:
    1, no incompatibility of drugs in a prescription .
     2, stirred evenly before it is added into feed.
    3, Sealed, in dark and dry place.

·Specification :1kg/bag, 25kg/drum.

·Specification : 24 months, avoid light and moisture.

Dihydropyridine (diludin) is a novel antioxidant vitamin stabilizer and animal growth promoter, has a natural antioxidant vitamin E in some role. It was the first animal and vegetable oils used in anti-oxidants, is the medical care for the prevention and treatment of cardiovascular disease drug. 70 years of the 20th century, the former Soviet Union experts Latvia has found that promoting growth of livestock and poultry, from countries around the world have started related research. In addition to promoting growth of livestock and poultry, but also to improve animal dihydropyridine product quality, improve the reproductive performance of animals and disease control and other functions. Our studies on the dihydropyridine of the 20th century began in the early 80s, several companies now have to start mass production, and put to use, to achieve better results. This article discusses the biological function of dihydropyridine, mechanism, and applications in animal production, hope to produce a guide.

1, the biological function of Dihydropyridine

Antioxidant 1.1

Dihydropyridines has antioxidant, can inhibit the oxidation of biofilms in vivo, inhibition of lipid peroxidation compounds to enhance the biofilm glucose 6 - phosphate enzyme activity, stability, cells, natural antioxidants VE and some of the features similar. Xiao-Ting Zou et al (1998) found that dihydropyridines can significantly increase serum superoxide dismutase (SOD) activity, inhibit lipid peroxidation of compounds to protect the cell surface receptors and organelles. Yu-Long Ma et al (1999) reported that laying the body through increased dihydropyridine SOD, ALP activity and the level of T3 and other factors, the effective removal of free radicals [3]. Yu-Rong Li et al (2003) explored the dihydropyridine oxidation resistance of Nile tilapia effect, the results show that: dihydropyridines experimental group significantly reduced liver lipid peroxide (LPO) content and increase the body's antioxidant properties ; experimental group SOD activity is rising, the test dose range, the antioxidant properties increased with the dose increased.

1.2 enhance immune function

Wu is the military, etc. (2000) test showed that the diet supplemented chickens Dihydropyridines can improve the immune function of animals, and added to 150mg per kg of diet most significant effect of the serum antibody levels were significantly increased (P <0.01) , T lymphocyte percentage rise. Val Dmna AR (1990) reported that diets supplemented with dihydropyridine chicken blood can increase the T, B lymphocytes, the spleen and bursa weight gain; new bit Pang et al (1995) Haisaikesi parents on behalf of dihydropyridine female child to add test results show that dihydropyridine Newcastle disease antibody titers in serum can increase 25.61%, so that the percentage of ANAE + lymphocytes increased 25.12%. Li Chenghui et al (2004) in mid-lactation dairy cows diets 150mg/kg dihydropyridine, so the incidence of subclinical mastitis of 59.9% lower than the control group.

1.3 animal endocrine regulation

Dihydropyridine regulate the body's endocrine role. Li Cheng will wait (2001) study found that in chicks diets supplemented Dihydropyridines can increase their levels of serum T3, T4 decreased, both changes were reversed, cortisol levels decreased [8]. Zi-Rong Xu et al (1999) tests to prove: Dihydropyridines can add chicken serum T3, follicle-stimulating EPO (FSH), luteinizing hormone (LH) levels were increased 15.38% (P <0.05), 55.09% ( P <0.01) and 22.54% (P <0.05); serum uric acid decreased 20.72% (P <0.05); and serum T4, estradiol (E2) and progesterone (P) levels were not significantly different (P> 0.05). Hypothalamus, anterior pituitary cyclic adenosine monophosphate (cAMP) levels were increased by 21.30% and 22.22% (P <0.05).

Yu-Rong Li et al (2003) in the feed to add 3 different levels of dihydropyridine male Nile tilapia fed to explore adding the appropriate amount of dihydropyridine and on serum T3, T4 levels. The results showed that, 50mg/kg of serum T3 levels were significantly higher and the level of T4 are in the unpredictable.

YE et al (2004) test results show that dihydropyridine added in the diets increased the amount of 50mg/kg 150mg/kg by the time, AA broilers was also found in serum T3 levels rise; when the addition of the 150mg / kg when added to 200mg/kg, T3 levels but decreased, indicating that diets high Dihydropyridines can inhibit thyroid hormone secretion.

1.4 to promote the absorption of minerals

Gubin Deng (2001), guided by bipolar serosal electrodes implanted surface, while multi-channel electrode recording method, determination of the small intestine of sheep dihydropyridine integrated EMG migrating. The results showed that dihydropyridines can significantly enhance the myoelectric activity of the small intestine, and can slow down the intestinal chyme after the shift, is conducive to small intestinal digestion and absorption of nutrients [11]. Yue Wenbin et al (1997) reported that laying hens diets supplemented with dihydropyridine and iron, zinc preparations can improve feed efficiency, and promote the absorption of minerals [12]. The role and promote the body metabolism of dihydropyridine, but the exact mechanism needs further study.

2 Mechanism of Dihydropyridine

2.1 The resistance mechanism

Sniedze (1977) studied the liver cells of rats Dihydropyridine particles in vivo electron transport chain, NADPH-specific enzymes related to the relationship between the dihydropyridine and the terminal that cytochrome oxidase P-450 to form complexes, which inhibited the NADP-cytochrome C reductase activity, and for taking dihydropyridine no other on the microsomal enzyme induction effects. Odydents (1987) pointed out that the dihydropyridine compound with the oxidation of NADPH, and microsomal esterase related enzyme. Shows the antioxidant effect of dihydropyridine through the partition of microsomal electron transport activity of the enzyme NADPH achieved.

2.2 The mechanism of egg

Zi-Rong Xu et al (1999) study suggests that dihydropyridine SOD by increasing the activity of the body, which can effectively remove free radicals, inhibit lipid peroxidation compounds, maintaining cell membrane structure and function. This not only reduces the damage of the egg, increasing the effective number of egg cells, but also delay the aging body, thus extending the egg production cycle. At the same time, increased Dihydropyridines follicle stimulating hormone (FSH), luteinizing hormone (LH) levels and the hypothalamus, anterior pituitary cAMP content, indicating that dihydropyridine by enhancing the hypothalamus, pituitary endocrine function, and promote the gland pituitary FSH and LH secretion, thus promoting follicle growth and development, inhibit the follicle atrophy, increased egg production rate [9].

Yu-Long Ma et al (1999) that the proportion of dihydropyridine and shell eggs can increase the relative weight. The mechanism there are two possibilities: one is through the influence of vitamin D3 dihydropyridine metabolism or basal side of the membrane of intestinal cells of calcium-dependent ATP activity directly or indirectly, to promote intestinal absorption of calcium; the other is the second pyridine and hydrogen present in the uterus of carbonic anhydrase activity, since the enzyme that catalyzes the metabolism of the eggshell gland mucosa of HCO3-generated CO2 hydration reaction. Both could make more calcium can be deposited on the surface of the shell, thus increasing the relative egg weight and eggshell weight.

2.3 The impact of the mechanism of animal semen quality

Male animal reproductive organs and reproductive function depends on the hypothalamus and pituitary regulation between, the hypothalamus - pituitary - gonadal axis. Hormones FSH, LH and T is the spermatogenesis and mature most major hormones. And Yu et al (2005) found that dihydropyridines in significantly increased serum FSH, LH and T levels, involved in the mouse hypothalamus - pituitary - gonadal axis regulation, which affects the reproductive function in mice to improve the quality of semen in mice.

2.4 promote the growth mechanism

Thyroid hormone in the body's growth and development is widely involved in regulating metabolism, growth is very important factor in poultry. T3 levels in vivo was positively correlated with growth rate. T3 levels increased to a certain extent, can promote cell differentiation, tissue and organ development, in the nerves, muscles, bones and play a role in gonadal development. Zhang Hong Chai et al (2005) reported that appropriate amount of Dihydropyridines can promote the growth of Yucheng Ji, improve egg production performance. The mechanism: on the one hand may be related to increased blood concentrations of T3; the other hand, dihydropyridine may also inhibit the secretion of glucocorticoids.

2.5 Mechanism to improve the carcass

Decreased serum urea nitrogen, indicating that the decomposition of protein was inhibited, prolonged retention of nitrogen. T3 is greater than the decomposition of fat synthesis, serum T3 levels, and promote the decomposition of fat, inhibit fat deposition. YE et al (2004) reported that abdominal fat percentage and serum T3 were negatively correlated, abdominal fat percentage and serum triglycerides were positively related to leg muscle ratio and serum urea nitrogen were negatively correlated. Dihydropyridine is to improve the performance of broiler slaughter of promoting assimilation of protein and inhibit fat synthesis in vivo interaction of these two results.

3 Dihydropyridines in Animal Production

3.1 improve the reproductive performance of animals
Guang et al (2004) study showed that feeding alone can significantly improve the dihydropyridine ram ejaculate volume and sperm motility, sperm deformity rate was significantly lower (P <0.01). Yue Wenbin et al (2000) Dietary bull dihydropyridine, the results showed that bull sperm motility test group, respiratory, 32Pi intake, rate of intact acrosome was significantly higher (P <0.01); The percentage of abnormal sperm was significantly lower than the control group (P <0.01). That dihydropyridines can improve the integrity of sperm plasma membrane, and promote sperm metabolism and energy transformation process, thereby improving the quality of bull semen. Tian Shujun et al (2000) per kg body weight in the concentrated feed 5mg / d once diludin added, the results show that the experimental group purebred Charolais per head than in the control group of fresh bull sperm viability, the amount of each semen and the effective monthly semen volume and sperm production increased by 12.75%, 0.7ml, 0.8ml and 304 (P <0.05).

Shi Jianguo et al (2003) study found that in fish feed, fed by 1g/kg diludin added carp broodstock 25d, female fecundity can increase 32.7%, male sperm production volume increased 28.1%. Yan-Ping Zhang et al (2005) per kg eel diets fed 150mg dihydropyridine pro-female eel 40d, the experimental group sexual maturity coefficient, absolute fecundity, hatching rate was significantly higher in the absolute fecundity of female eel 13.24% of eggs increased the hatching rate increased 20.64%.

Zhulian Ying et al (2004) reported that in the raccoon dog diets supplemented with 300mg/kg dihydropyridine, the breeding rate, both litter size, litter birth weight and Tsai raccoon survival rates were respectively 22.2% increase compared to the control group, 9.33% , 8.82% (P <0.05) and 16%. That dihydropyridine reproductive performance of the raccoon dog has a significant improvement.

3.2 to promote animal growth and improve performance

Zhang Hong Chai et al (1998) that the dihydropyridine on the growth performance of growing pigs promote, 25mg/kg add levels to promote the growth trend of pigs, average daily gain increased 4.42%. Wu Huadong et al (2003) reported that dihydropyridines can significantly improve the daily gain of pigs (P <0.01), and pig slaughter rates tend to increase, decrease fat thickness, eye muscle area improved; while pointed out that the best adding amount per ton of dihydropyridine feed 50 ~ 150g.

Zhang Hong Chai et al (2005) study showed that the addition of dietary levels of dihydropyridine 50 ~ 150mg/kg, with the addition of the increase in dihydropyridine, Yucheng Ji weight upward trend, adding dihydropyridine 37d, its body weight was significantly higher (P <0.01). YE et al (2004) reported varying degrees of dihydropyridine slaughter broilers improved performance, half of which eviscerated percentage, eviscerated rate added to the diet dihydropyridine best when the level of 50mg/kg, was significantly higher (P <0.05); leg muscle percentage level added to 150mg/kg best, with the control group there were significant differences (P <0.05); 150,200 mg / kg treatment group, rates of abdominal fat than the control group decreased by 0.29% and 0.30%.

Zheng Medium (1998) Dihydropyridines and VE test the application effect of cow study found that feeding can significantly improve Dihydropyridines milk yield (P <0.05) [26]. Yu-Rong Li et al (2003) study found that diets supplemented with dihydropyridine (50,100 mg / kg) daily weight gain of Nile tilapia can be increased 11.9% (P <0.05), 6.8%, weight specific growth rate 12.6% (P <0.05), 8.7%.

3.3 Prevention of fatty liver

Xiao-Ting Zou et al (2003) found that addition of 150mg/kg and 300mg/kg dihydropyridine layers can decrease abdominal fat were 35.4% (P> 0.05) and 46.9% (P <0.05), liver fat percentage decreased 32.4% (P <0.05) and 10.5% (P> 0.05), that dihydropyridine good lipid-lowering effects. Xiao-Ting Zou et al (2005) that dihydropyridines can promote the laying hens in the latter part of the migration of fat in the liver and the decomposition of body fat, reduce body fat deposition in chickens, and reduce free radical damage to liver function, to anti- the effects of fatty liver. Yu-Rong Li et al (2003) found that the experimental group can reduce Dihydropyridines tilapia liver fat (dry) content, but the serum activity of GOT and GPT had no effect.

3.4 to improve daily gain and feed efficiency of animals, improve product quality

Dvinskaya-LM et al (1997) in broiler diets dihydropyridine (20 ~ 50mg/kg), can increase daily gain and feed efficiency; Sprugh Ya Ya et al (1975) in pig feed added per head per day 25,50,100 mg dihydropyridine, increased average daily gain than the control group were 6.08%, 6.57% and 9.52%, feed consumption decreased 5.77%, 6.24% and 8.78%; Levin N (1982) in finishing pig diets dihydropyridine, average daily gain increased by 5.2%, feed conversion decreased by 3.4%; Rick donkeys, etc. (1992) to the calves, bred cows and beef cattle feeding dihydropyridine hybrids, average daily gain increased by 32.9%, 14.9% and 12.5%, but on the forage to concentrate had no effect on feed intake; diet containing 0.01% dihydropyridine, ewes, rams and young sheep weight gain were increased by 19.07%, 13.44% and 18.25%; broilers at Add 100 ~ 150mg/kg food dihydropyridine, significantly improved daily gain and increase the flavor substances in the muscle; finishing pigs (60 ~ 100kg weight stage) feed Feeding 50mg/kg dihydropyridine, can significantly promote the growth of fattening pigs, dressing percentage and lean meat percentage increased, and significantly increased IMP content, improve the quality of meat.

4 Conclusion

Dihydropyridine as a new type of green feed additive, has been widely used in foreign animal production. Practice has proved that dihydropyridines can promote animal growth and development not only to improve production performance, reproductive performance, and enhance immune function; and feed safety, has a broad development prospects. At present, China has synthesized dihydropyridine market. However, the optimal addition stage of the animals and the best dosage, and other antioxidants Dihydropyridine the relationship between issues remain to be studied further. Through these studies, the application can provide a more dihydropyridine broad scientific basis