CN105146139A - Application of powdered milk substitute for raising weaning lambs of Qianbei ma goats - Google Patents

Abstract

The invention discloses the application of a milk substitute powder in raising weaned lambs of Qianbei Ma sheep. The milk substitute powder is supplemented in the basic diet of Qianbei Ma sheep lamb; the basic diet consists of whole plant corn, distiller's grains Composed of fine material mixture. The amount of supplementary feeding of the milk replacer is 4% to 6% of the dry matter weight of the basic diet of Qianbei Ma sheep weaned lambs. Supplementing milk replacer with an appropriate level of diet can improve the average daily gain and nutrient digestibility of Qianbei Ma sheep weaned lambs, reduce the feed-to-weight ratio, and improve the feed conversion rate; it can also effectively enhance the plasma anti-oxidative stress ability and protein utilization and immunity.

Description

Application of Milk Substitute Powder in Feeding Weaned Lambs of Qianbei Ma Sheep

technical field

The invention relates to the technical field of goat feeding, in particular to the application of a milk replacer in feeding weaned lambs of Qianbei Ma goats.

Background technique

Qianbei Ma sheep is one of the three excellent local goat breeds in Guizhou Province. This breed of goat is the product of long-term selection and natural selection by the working people in the producing area. It has good adaptability to the local natural ecological conditions, has the characteristics of roughage resistance, strong disease resistance, wide adaptability, delicious and tender meat, and good quality hide , Excellent production performance and so on. In May 2009, during the review and identification process of new genetic resources organized by the Ministry of Agriculture, the expert group of the Ministry of Agriculture gave a high evaluation to this breed of goat, and believed that "the Qianbei Ma goat has its own characteristics and is quite different from the Chengdu Ma goat. ", thus successfully passed the on-site appraisal by the expert group, and was approved as a new genetic resource by the expert committee of the Ministry of Agriculture in December of the same year. Qianbei Ma sheep are mainly produced in Renhuai and Xishui in the north of Guizhou, and are also distributed in the southwest of Chishui, northwest of Zunyi, south of Tongzi and northeast of Jinsha. Qianbei Ma sheep is a short-haired goat with both skin and meat. It has a strong physique, a wide and deep chest, a straight back and a waist, and a thick neck. Light, adult coat color becomes darker. The slaughter rate of Qianbei Ma sheep is 56.6%. It has good meat production performance, high reproduction rate and strong disease resistance. It is suitable for extensive breeding in mountainous areas and has great development potential. However, in actual breeding, the growth performance and plasma biochemical indicators of Qianbei Ma sheep weaned lambs are often not ideal, and there are problems such as low feeding efficiency.

Contents of the invention

The purpose of the present invention is to provide the application of a milk substitute powder in the breeding of Qianbei Ma sheep weaned lambs, so as to improve the breeding efficiency of Qianbei Ma sheep.

Technical scheme of the present invention is such:

The application of a milk replacer in the feeding of Qianbei Ma sheep weaned lambs, which is to supplement the milk replacer in the basic diet of Qianbei Ma sheep lamb; the basic diet is mixed with whole plant corn, distiller's grains and concentrate material composition. The supplementary feeding period of the milk replacer starts after the weaning of the Qianbei Ma sheep lambs, and the supplementary feeding method is directly added to the diet of the Qianbei Ma sheep lambs, while the method in the prior art is usually to mix the milk replacer with water Feeding with a baby bottle after evening has a large workload, high labor intensity, and low efficiency; lambs in cold weather cannot finish drinking in time, and then drink after cooling, which is likely to cause health problems such as diarrhea. The supplementary feeding amount of milk replacer is 4% to 6% of the dry matter weight of the basic diet of Qianbei Ma sheep lambs. The preferred supplementary feeding amount is 4%.

Wherein, the concentrate mixture is made of the following components by weight percentage: corn 66%, soybean meal 18%, bran 12%, urea 1%, premix 1%, calcium hydrogen phosphate 1.5%, salt 0.5% . The milk substitute powder is made of the following components: vitamin A, vitamin D3, vitamin E, milk protein powder, whey powder, vegetable protein powder, calcium carbonate, calcium bicarbonate, amino acid, salt, ethoxyquinoline.

The technical effect of the present invention: ① Supplementary feeding of milk replacer powder can increase the dry matter intake of lambs ( P <0.05) and the apparent digestibility of dry matter, crude protein, neutral detergent fiber, acid detergent fiber and crude ash and nitrogen balance status and biological value ( P <0.05), but had little effect on the digestibility of crude fat ( P >0.05); ②Adding 4%-6% milk replacer to the feed could increase the average daily gain of lambs ( P <0.05), reducing the trend of feed-to-weight ratio ( P <0.05); ③Looking at the whole period, 4% level of milk replacer can improve the total antioxidant capacity of lamb plasma, superoxide dismutase, catalase, lysozyme Enzyme activity ( P <0.05) reduced the levels of malondialdehyde and urea nitrogen ( P <0.05), but had no significant difference on glutathione peroxidase, glucose, and alkaline phosphatase ( P >0.05). It can be seen that supplementing the appropriate level of milk replacer with dietary supplementation can improve the average daily gain and nutrient digestibility of Qianbei Ma sheep lambs, reduce the feed-to-weight ratio, and improve the feed conversion rate; it can also effectively enhance the plasma anti-oxidative stress ability, Protein utilization and immunity.

Description of drawings

Figure 1 is a schematic diagram of the temperature and humidity index of the sheep pen during the trial period.

Detailed ways

The present invention will be described in further detail below in conjunction with embodiment.

Example 1:

1 Materials and methods

1.1 Experimental design

The experiment was carried out in a large-scale Qianbei Ma sheep breeding sheep farm in Guizhou Province, with nearly 1,500 sheep on hand, which is a large-scale commercial sheep farm. According to the principle of close body weight, 40 4-month-old lambs in good body condition were randomly divided into 4 groups according to the single-factor randomized block test design: control group (15.02±0.59kgBW), treatment group 1 (14.56±0.92kgBW ), treatment 2 groups (15.53±1.60kgBW), treatment 3 groups (14.90±0.89kgBW), 10 rats in each group. There was no significant difference in the initial body weight of the lambs in each group ( P >0.05). Based on the dry matter content of the diet, the levels of milk replacer in each group were 0%, 2%, 4%, and 6%, respectively. The basic dietary formula of Qianbei Ma sheep is composed of whole plant corn, concentrate and a small amount of distiller's grains, and its nutritional components are shown in Table 1.

The lambs were managed uniformly throughout the experiment. The lambs were house-fed in separate pens, fed after cleaning the feeding troughs at 9:00 and 18:00 every day, and fed ad libitum. The sheep house is naturally ventilated, leaving enough space for exercise and free drinking water. The test lasted 40 days in total: including a pre-feeding period of 10 days, the first 7 days were used for the physiological stress and gregarious adaptation caused by the transitional lamb grouping, and the next 3 days were gradually fed with milk replacer at a level of <10% set by each group (that is, treatment 1 Group, group 2, and group 3 milk replacer powder <1.5g, 3g, 4.5g respectively), so that the lambs can adapt to the taste of milk replacer before the main test period; the main test period is 30 days, divided into 3 periods, each period is 10d. Therefore, the whole test cycle includes 4 periods: the pre-feeding period (1~10d), the 1st period of the main test (11~20d), the 2nd period of the main test (21~30d), and the 3rd period of the main test (31~40d).

1.2 Collection of feed samples

In order to accurately grasp the dietary nutrients of the lambs, the dietary samples were collected twice a day during the experiment and stored at -20°C. After the test is completed, the mixed diet samples are dried and crushed for the determination of crude protein (crude protein, CP), crude fat (etherextract, EE), neutral detergent fiber (neutraldetergentfiber, NDF), acid detergent fiber (aciddetergentfiber, ADF) ), crude ash (Ash).

1.3 Detection indicators

1.3.1 Temperature and humidity environment parameters

In order to ensure accurate measurement of temperature and humidity in the sheep house, hang the thermo-hygrometer at the same height as the lamb in the middle of the sheepfold, and ensure that the thermo-hygrometer is normally ventilated and protected from sunlight and rain. After adaptation during the pre-feeding period, the temperature and relative humidity of the sheep house at 8:00, 14:00, and 20:00h were recorded every 1 day from the beginning of the trial period, and the average value was calculated for three times. The temperature and humidity index was carried out with reference to the following formula:

THI=0.8×(AT)+[RH/100]×(AT-14.4)+46.4

In the formula: THI represents the temperature and humidity index, AT represents the ambient temperature, and RH represents the relative humidity. When THI<70, it means that the lamb is in a comfortable (non-heat stress) environment; when 70<THI<75, it means that the lamb is in a mild heat stress environment; when 75<THI<78, it means that the lamb is in In a moderate heat stress environment; when THI>78, it indicates that the lamb is in a severe heat stress environment.

1.3.2 Growth performance

1.3.2.1 Dry matter intake

Accurately record the amount of feeding and remaining material for each feeding, and calculate dry matter intake (DMI) = feeding amount - remaining amount according to the moisture content.

1.3.2.2 Nutrient digestibility and nitrogen balance

The test adopts the method of total feces collection, and the feces samples are collected on the last day of each stage for a total of 4 days, and they are mixed as the mixed feces samples of this group of lambs. The feces are collected as they are discharged. The collected fresh feces are accurately weighed, mixed, and 20% is taken as a sample, and 10% hydrochloric acid is added to 10% of the weight, and stored at -20°C. After the test, mix, dry, pass through a 1mm sieve and pulverize, measure DM, CP, EE, NDF, ADF, Ash, and use to calculate the apparent digestibility of nutrients.

While collecting feces, use a plastic film to surround the sheepfold along the bottom and cut a small opening at the bottom to collect urine. Each time the collected urine is filtered through 4 layers of gauze, the volume is recorded, and 10% (volume fraction) is taken as a sample , adjust the pH to 2 with 10% hydrochloric acid, record the amount of acid added, and store the N content at -20°C for the calculation of N balance.

Nutrient digestibility (%) = (nutrient intake - nutrient manure content) / nutrient intake × 100%.

The calculation formula for N balance is as follows:

Absorbed nitrogen = ingested nitrogen - manure nitrogen;

Deposited nitrogen = ingested nitrogen - (fecal nitrogen + urine nitrogen);

Nitrogen digestibility = (ingested nitrogen - manure nitrogen) / ingested nitrogen × 100%;

Net protein utilization = deposited nitrogen/ingested nitrogen × 100%;

Biological value of nitrogen (biological value, BV) = deposited nitrogen/absorbed nitrogen × 100% ^[16] .

1.3.2.3 Weight gain and material weight ratio

After the gregarious adaptation in the pre-feeding period, the body weight on the 10th day was taken as the initial weight basis, and the weight was weighed at the end of each stage, and the body weight before the morning feeding on the 20th day, 30d, and 40th day was recorded respectively, and the weight gain was calculated. Body weight is the last weight.

A. Total weight gain = final weight - initial weight;

B. Average daily weight gain = (final weight - initial weight)/30.

C. Feed-to-weight ratio = dry matter intake/average daily gain.

1.3.3 Blood indicators

Taking the entry into the trial period as the initial period of blood collection, 10ml of blood was collected from the jugular vein on the 10th, 20th, 30th, and 40th days before morning feeding with disposable heparin sodium anticoagulant vacuum blood collection tubes, and centrifuged at 3000r/min (1006.20g) for 15min. The upper layer of plasma was collected and stored in a -20°C refrigerator for the determination of plasma anti-oxidative stress indicators: total anti-oxidative stress capacity (T-AOC), superoxide dismutase (SOD), glutathione excess Oxide dismutase (GSH-Px), catalase (CAT), malondialdehyde (MDA), biochemical indicators: glucose (Glu), urea nitrogen (PUN), alkaline phosphatase (AKP), lysozyme ( LZM). The detection kit was provided by Nanjing Jiancheng Institute of Bioengineering.

1.4 Data processing and statistical analysis

Experimental data are expressed as mean ± standard deviation (mean ± SD). After basic sorting of data with Excel2010, SAS9.3 statistical processing software was used for one-way analysis of variance. Duncan's method was used to conduct multiple comparisons of the differences in the indicators of each group, and the significant level of differences among the groups was set at P <0.05.

2 results

2.1 Environmental parameters

It can be seen from Figure 1 that the daily average temperature of the surrounding environment of the test sheep ranged from 23.50 to 29.43°C, with an average of 26.59°C (±2.87); the daily average relative humidity ranged from 53.33 to 80.33%, with an average of 68.42% (±10.43 ). From this, the daily average temperature and humidity index was calculated to be between 75.13 and 79.78, with an average of 77.43 (±2.00), indicating that the test sheep were kept in a breeding environment close to severe heat stress.

2.2 Growth performance

2.2.1 Dry matter intake

It can be seen from Table 2 that in the first stage of the experiment (pre-feeding period), the DMI of each group did not change significantly, and the difference was not significant ( P >0.05). However, as time went on, in the second and third stages, the DMI of each treatment group was significantly higher than that of the control group, and the difference reached a significant level ( P <0.05), and the treatment group 2 was the highest. At the fourth stage, although the DMI of the control group was not significantly different from that of the treatment group ( P >0.05), it was still at the lowest level. From the perspective of the whole test period, the DMI of each treatment group was significantly higher than that of the control group ( P <0.05), and the treatment group 2 was the highest, which was 16.50% higher than that of the control group.

2.2.2 Nutrient use efficiency

2.2.2.1 Apparent digestibility

From the perspective of the whole test period, supplementary feeding of milk replacer powder can improve the apparent digestibility of DM, CP, EE, NDF, ADF and Ash (Table 3). For DM, treatment group 1, group 2, and group 3 were 5.47%, 11.61%, and 5.88% higher than the control group, respectively, and treatment group 2 was significantly higher than the control group ( P <0.05). For CP, the treatment group 2 was the highest, which was significantly higher than the control group by 19.21% ( P <0.05), and the other groups had no significant difference ( P >0.05). For EE, there was no significant difference among the four groups ( P >0.05), and the treatment group 1 and 2 were slightly higher than the control group. For NDF and ADF, each treatment group was significantly higher than the control group ( P <0.05), and the treatment group 2 was the highest; treatment group 2 was significantly higher than treatment group 1 and group 3 at the same time ( P <0.05). For Ash, the treatment group 2 was the highest, which was significantly higher than the other 3 groups ( P <0.05).

2.2.2.2 Nitrogen balance

It can be seen from Table 4 that there was no significant difference among the treatment groups ( P >0.05), but they were all significantly higher than the control group ( P <0.05), which were 10.88%, 16.51%, and 12.32% higher, respectively. For fecal nitrogen, there was no significant difference among the groups ( P >0.05), and the treatment group 2 was the lowest. For urinary nitrogen, treatment group 1 and treatment group 3 were higher, significantly higher than control group and treatment group 2 ( P <0.05). For nitrogen absorption, the control group was the lowest, significantly lower than the treatment groups ( P <0.05), 14.13%, 28.05%, and 17.36% lower than treatment group 1, 2, and 3, respectively. For deposited nitrogen, treatment group 2 was significantly higher than control group (44.48%), treatment group 1 (35.52%) and group 3 (31.94%; P <0.05). The apparent digestibility of nitrogen was not significantly different among the treatment groups ( P >0.05), and the treatment group 2 was the highest, which was significantly higher than the control group at 19.21% ( P <0.05). The total utilization rate of nitrogen was the highest in treatment group 2, which was 54.15% higher than that in the control group ( P <0.05), 47.34% in treatment group 1 ( P <0.05), and 41.85% in treatment group 3 ( P <0.05). The biological value of nitrogen was highest in treatment group 2, which was higher than that in the control group by 21.63% ( P <0.05), treatment group 1 by 21.93% ( P <0.05), and treatment group 3 by 21.50% ( P <0.05).

2.2.3 Weight gain and material weight ratio

It can be seen from Table 5 that during the 30-day trial period, although the initial weight and final weight of lambs in the four groups did not change significantly ( P >0.05), the total weight gain of each treatment group increased significantly. Group 1, Group 2, and Group 3 were 15.48%, 50.32%, and 67.10% higher than the control group, respectively, and treatment groups 2 and 3 were also significantly different from the control group ( P <0.05). Correspondingly, the average daily gain showed the same effect, and the treatment groups 2 and 3 were significantly higher than the control group ( P <0.05). From the perspective of feed-to-weight ratio, as the level of milk replacer powder increases, the feed-to-weight ratio gradually decreases. Throughout the test period, the conversion rate of treatment group 3 was the highest, followed by treatment group 2, which were all lower than those of treatment group 1 and the control group, and the difference reached a significant level ( P <0.05).

Note: The initial weight is the value of the 10th day of the lamb.

2.3 Plasma anti-oxidative stress capacity

It can be seen from Table 6 that milk replacer can improve the ability of lambs to resist oxidative stress. There was no significant difference in the plasma T-AOC levels of sheep in each group at the 10th, 30th, and 40th time points ( P >0.05); but on the 20th day, treatment groups 1 and 2 were significantly higher than those in the control group ( P < 0.05), increased by 58.38% and 61.27% respectively. From the perspective of the whole test period, the effect of treatment group 2 was the best, which was significantly higher than that of the control group by 34.90% ( P <0.05), but there was no significant difference with treatment group 1 and group 3 ( P >0.05).

For the plasma SOD level, the milk replacer did not show an effect on the 30th day of the test, and the differences among the groups were not significant ( P >0.05); on the 40th day, the plasma SOD level of the treatment group 2 was the highest, which was higher than that of the control group and the treatment group 1. They increased by 18.39% and 28.28% respectively ( P <0.05). From the perspective of the entire test period, the SOD levels in the treatment group 2 were the highest, and tended to be higher than those in the control group (13.92%, P <0.1).

Similar to T-AOC, there was no significant difference in plasma GSH-Px levels at the 10d, 30d, and 40d time points of each group ( P >0.05); on the 20th day, the control group was significantly higher than that of the treatment group 3 ( P <0.05), and the treatment group There was no significant difference between the two groups ( P >0.05). Throughout the test period, there was no significant difference in the level of GSH-Px among the groups ( P >0.05), but the treatment group 2 was the highest overall.

At each blood collection time point, the CAT levels in each group did not change much, and the differences were not significant ( P >0.05). During the whole test period, the level of treatment group 2 was the highest, which was significantly higher than that of the control group by 21.77% ( P <0.05); the difference among the other groups did not reach a significant level ( P >0.05).

For the plasma MDA level, on the 10th day, the treatment group 3 was significantly higher than the treatment group 1 ( P <0.05), 21.46% higher than the control group ( P >0.05); on the 20th day, the treatment group 2 was lower than the treatment group 1 ( P <0.05); on the 30th and 40th days, there was no significant difference in plasma MDA levels ( P >0.05). During the whole test period, the MDA level in the treatment group 2 was the lowest, which was significantly lower than that in the control group by 15.64% ( P <0.05).

2.4 Plasma biochemical indicators

It can be seen from Table 7 that for the plasma Glu level, there was no significant difference between the experimental groups on the 10th day ( P >0.05), and treatment groups 1 and 2 were significantly lower than the control group ( P <0.05); The difference was not significant ( P >0.05); until the 40th day, the treatment group 3 was significantly higher than the control group and treatment group 2 ( P <0.05). From the perspective of the whole test period, there was no significant difference in plasma Glu levels among the groups ( P >0.05).

On the 30th day of the test, there was no significant difference in the plasma PUN level of the lambs in each group ( P >0.05); on the 40th day, the level of PUN in treatment group 2 was the lowest, which was significantly lower than that of the control group ( P <0.05). During the whole test period, the treatment group 2 was the lowest, which was significantly lower than the control group 17.96% ( P <0.05) and treatment group 1 13.80% ( P <0.05).

Supplementary feeding of milk replacer had a limited effect on the plasma AKP level of lambs, and there was no significant difference among the groups at each blood collection point and throughout the test period ( P >0.05).

For plasma LZM levels, the levels of the three experimental groups were higher than those of the control group at four time points, but the difference did not reach a significant level ( P >0.05). During the whole test period, the level of LZM in the treatment group 2 was the highest, which was 33.27% higher than that in the control group, and the difference was significant ( P <0.05).

3 Discussion

3.1 Effect of milk substitute powder on the growth performance of Qianbei Ma sheep

3.1.1 Dry matter intake

Feed intake is a measure of the amount of nutrient intake and is an important factor in determining the growth rate of animals. Nutrients eaten by animals can be used for production only after their maintenance needs are met. Without adequate feed intake, animals cannot reach their full growth potential. Throughout the test, the DMI of the 3 treatment groups were significantly higher than that of the control group ( P < 0.05), and the treatment 2 group had the highest DMI, which also had the highest N intake (Table 4). This is because the milk replacer used in the test contains milk protein powder, whey powder, etc., which have the odor of maternal milk, and have obvious nutritional characteristics, which can improve the palatability of the diet and promote the lamb's feed intake; but DMI does not change with the level of milk replacer. It increases linearly with the increase of , and reaches the maximum value at 4% level, suggesting that if the milk source taste of milk replacer is too strong, the palatability may be reduced. The animals used in the experiment were weaned lambs. The results also suggest that weaning is not an active choice of lambs. Supplementing them with an appropriate amount of milk replacer by directly adding them in the diet can still stimulate their feed intake and increase their feed intake.

3.1.2 Nutrient digestibility and nitrogen balance

Digestibility is a comprehensive reflection of animals' digestion characteristics of feed, which can indicate the degree of digestion and utilization efficiency of feed nutrients by the digestive tract. The experimental research shows that the digestibility of various nutrients and the absorption rate and deposition rate of N of the test sheep in the three treatment groups are better than the control group to a certain extent, and the treatment in the second group is the most obvious. This is because the differences in nutrients and concentrations contained in different levels of milk replacer powder affect the digestion and metabolism of nutrients in animals, thereby changing the rate of digestion and metabolism of nutrients. In this experiment, the DMI of goats in each treatment group was significantly higher than that of the control group, which provided a strong guarantee for the improvement of goat digestibility. Because the increase in feed intake of goats promotes the continuous reproduction of rumen microorganisms, the volatile fatty acids and microbial proteins produced by rumen fermentation can provide a material basis for the growth of test goats; Secretion has a promoting effect, and roughage can promote the development of the posterior digestive tract, thereby promoting the secretion of digestive enzymes. In general, adding appropriate milk replacer powder in the diet can enhance the digestibility of nutrients and the state of N balance of lambs, which is beneficial to the deposition and utilization of nutrients and improves animal growth performance.

3.1.3 Weight gain and material weight ratio

Reducing the feed-to-weight ratio and increasing the daily weight gain are the important purposes of animal feeding experiments, and are of great significance to improving the efficiency of raising sheep. This experimental study shows that supplementing lamb milk replacer can significantly increase its body weight gain and average daily gain, promote its rapid growth, and shorten the time to slaughter; it can significantly reduce the ratio of diet to weight and improve feed conversion rate.

3.2 Effect of milk replacer powder on blood metabolism indexes of Qianbei Ma sheep

3.2.1 Anti-oxidative stress capacity

The blood circulates continuously in the body, and its metabolic index level can objectively reflect the metabolic state and physiological function. In the test, the increase of blood T-AOC, SOD, GSH-Px, and CAT and/or the decrease of MDA often indicates that the ability to resist oxidative stress is enhanced, and vice versa. Milk replacer can significantly increase the plasma T-AOC, SOD, CAT levels of lambs, and at the same time significantly reduce the plasma MDA levels. This is because, after supplementing milk replacer, the feed intake of the lamb increases, which not only meets the nutritional needs of the rumen microorganisms, but also provides nutrients for the growth of the lamb, which can remove free radicals to a certain extent and reduce the oxidation of the lamb. Damage, enhance the body's immune defense system, thereby improving the lamb's ability to resist oxidative stress. It can be seen that from the perspective of animal nutrition research, increasing the levels of T-AOC, SOD, GSH-Px, and CAT and reducing the level of MDA are effective measures to enhance the ability to resist oxidative stress. It is worth mentioning that the ability to resist oxidative stress does not continue to increase with the increase in the level of milk replacer, and there is a threshold (4% in this test). This is exactly consistent with the results of growth performance, that is, 4% level of milk replacer increases the lamb's feed intake and nutrient digestibility, indicating that it is not appropriate to add too much milk replacer in production.

3.2.2 Plasma biochemical indicators

Changes in blood biochemical parameters are a reflection of changes in tissue cell permeability and metabolic functions of the body. Glu is the energy source and metabolic intermediate product of living cells, and is an important indicator to measure the energy balance in animals. The high temperature season will lead to the hyperfunction of the animal adrenal cortex and medulla, the increase of the level of glucocorticoid in the plasma will strengthen the catabolism of the animal body, and the blood sugar level will increase to resist the pressure on the body caused by the external high temperature. The Glu level of the lambs in the two groups treated by the present invention was significantly lower than that of the control group on the 10th day and 40th day, indicating that adding suitable milk replacer powder to the diet can effectively alleviate the heat stress of the lambs.

Urea nitrogen is mainly derived from the liver and is the main end product of protein metabolism in the body. It constitutes most of the non-protein nitrogen in the blood and is one of the indicators reflecting the utilization efficiency of dietary protein. Plasma urea nitrogen content is related to the total amount of nitrogen-containing substances in the diet and the utilization rate of protein. When the nitrogen-containing substances in the diet increase or the protein utilization rate decreases, the plasma urea nitrogen content can increase, and the decrease of the urea nitrogen level can be Protein deposition in other parts provides sufficient raw materials such as amino acids. In this experiment, the levels of urea nitrogen in the two treatment groups were significantly lower than those in the control group at the end of the experiment and throughout the experiment period, indicating that an appropriate level of milk replacer powder can effectively improve the utilization rate of feed protein. The reason is that urea nitrogen has an important relationship with the amount and digestibility of digestible protein. Milk replacer is rich in digestible vegetable protein, which increases the nitrogen nutrients in the diet and provides a large amount of amino acids and other raw materials for the body, making the Lower blood urea nitrogen levels.

AKP is widely distributed in various organs of the body. It is an enzyme that can dephosphorylate the corresponding substrate. It is one of the most commonly used labeling enzymes for immunodiagnostic reagent products. When the animal is subjected to external stress, it can cause tissue cell damage in the body, and AKP in the tissue enters the blood, increasing the plasma AKP concentration. There was no significant difference in plasma AKP levels among the groups in this experiment, indicating that the milk replacer in the diet had less stress on the goats and did not cause damage to the tissue cells of the lambs; Alleviating the impact of summer heat stress on lambs has the effect of improving tissue damage.

LZM is a low-molecular-weight heat-labile basic protein that can destroy the structure of bacterial cell walls. It is a non-specific immune factor in normal body fluids and tissues. In this experiment, the LZM level of lambs in the treatment group was higher than that of the control group at each time point, and the treatment group 2 was significantly higher than the control group throughout the feeding period, indicating that milk replacer can eliminate the impact of non-specific immune response on lambs, Helps strengthen lamb immunity.

4 Conclusion

Under the conditions of the present invention, milk substitute powder is as follows to the test conclusion of Qianbei Ma sheep weaned lamb:

It can improve DMI and nutrient utilization rate, increase daily gain, reduce feed-to-weight ratio, and promote growth performance; it can increase plasma T-AOC, SOD, CAT, LZM content, reduce MDA, PUN, AKP levels, and help enhance antioxidant Stress capacity, immunity and protein utilization.

On the whole, under the conditions of the present invention, the preferred addition level of milk replacer for Qianbei Ma sheep weaned lambs is 4%.

Certainly, the above are only specific application examples of the present invention, and there are other implementation modes in the present invention, and all technical solutions formed by equivalent replacement or equivalent transformation all fall within the scope of protection required by the present invention.

Claims (4)

1. An application of a milk replacer in the raising of weaned lambs of Qianbei Ma sheep, characterized in that: the milk replacer is supplemented in the basic diet of Qianbei Ma sheep lamb; the basic diet consists of whole plant corn, distiller's grains and concentrate mixture; the supplementary feeding period of the milk replacer starts after the weaning of Qianbei Ma sheep lambs, and the supplementary feeding method is directly added to the diet of Qianbei Ma sheep lambs. 2. The application of the milk replacer according to claim 1 in raising weaned lambs of Qianbei Ma sheep, characterized in that: the amount of supplementary feeding of said milk replacer is 1/2 of the dry matter weight of the basic diet of Qianbei Ma sheep lambs. 4% to 6%. 3. The application of the milk replacer according to claim 2 in the feeding of Qianbei Ma sheep weaned lambs, characterized in that: the concentrate mixture is made of the following components by weight percentage: corn 66%, soybean meal 18% %, bran 12%, urea 1%, premix 1%, calcium hydrogen phosphate 1.5%, salt 0.5%. 4. The application of the milk replacer according to claim 2 in the feeding of Qianbei Ma sheep weaned lambs, characterized in that: the milk replacer is made of the following components: vitamin A, vitamin D3, vitamin E, milk Protein powder, whey powder, plant protein powder, calcium carbonate, calcium bicarbonate, amino acid, salt, ethoxyquinoline.