Effect of Caragana korshinskii Silage at Different Growth Stages on the Feeding of Livestock

Bai HAN, Mei HAN*, Han WU, Yuman LIN, Jinjun HE, Rong LIU

1. Ordos Forestry and Grassland Research Institute, Ordos 017000, China; 2. Ordos Meteorological Bureau, Ordos 017000, China; 3. Agriculture and Animal Husbandry Technology Extension Center of Etuoke Banner, Ordos 017000, China

Abstract [Objectives] Caragana korshinskii resources are rich in Ordos with a large planting area, but they have not been fully and reasonably utilized. This study aims to effectively convert C. korshinskii into high-quality feed, improve the quality of milk and meat of herbivores and increase production. [Methods] The utilization of C. korshinskii in feed was studied in various aspects, the factors were selected, the level was determined, and the multi-factor experiment—orthogonal experiment was conducted. [Results] The effect on the growth of sheep was in the order of silage >C. korshinskii feed >corn stalk silage >hay meal, and the effect on the growth of goats was in the order of hay meal >C. korshinskii feed >silage >corn stalk silage. [Conclusions] From the analysis of the range results, the best level combination was selected：in different growing seasons, C. korshinskii branch and leaf silage in full-bloom stage had the greatest effect on the growth of sheep and goats, and the fattening effect was the best; among the different silage methods of C. korshinskii, the C. korshinskii—corn stalk mixture silage had a good feeding effect for sheep and goats.

Key words Forage, Caragana korshinskii, Silage, Development and utilization

1 Introduction

Caraganakorshinskiihas the characteristics of developed root system, strong germination ability, strong adaptability, barren soil tolerance, cold tolerance, drought tolerance and so on. In arid sandy land, desert and semi-desert areas, it is regarded as an excellent tree species with excellent stress resistance, and it is mainly planted for wind prevention, sand fixation and water and soil conservation. It has garnered more and more attention in forest land construction and ecological environment improvement, and has been popularized in practice[1]. Li Wenlongetal.used multi-level fuzzy comprehensive evaluation method to evaluate the growing ecosystem health from the aspects of wind prevention and sand fixation effect ofC.korshinskii[2]. The evaluation results provide a quantitative basis for the culture and management of artificial sand-fixing forest in sandy area. AlthoughC.korshinskiitree species have been widely used in windbreak and sand fixation and farmland protection, there are relatively few studies on the processing and utilization ofC.korshinskii. In the 1990s, most of the utilization ofC.korshinskiiwas still in the initial stage of direct grazing. Because of the biological characteristics ofC.korshinskii, it must be transplanted after a growth period of 3-5 years[3], producing a large number ofC.korshinskiibranches as abandoned dead branches, which can not be used effectively. Now after biological and chemical treatment, it has become an important non-grain feed raw material. Especially after snow covers the grassland in winter, it becomes the only "life-saving grass" for sheep to eat.C.korshinskiihas high nutritional value, including 22.9% crude protein, 4.9% crude fat, 27.8% crude fiber; 27.4% crude protein, 12.8% crude fat and 31.6% nitrogen-free extract in seeds. Cai Jikunetal.[4]treatedC.korshinskiiwith EM bacteria liquid for fermentation, and the fermented material was eaten by sheep, which increased their weight obviously and had better disease resistance. Tian Jinmeietal.[5]fermentedC.korshinskiigrass by feed fermentation technology, which had good palatability and weight gain effect.

2 Materials and methods

2.1 Test materialsFresh branches ofC.korshinskiiwere harvested in vegetative stage, full flowering stage, podding stage and ripening stage as the main materials, mixed with corn and all kinds of conventional feed. According to the quantity of livestock, there were 8 rectangular semi-underground silage cellars (in meters), that is, the size of the bottom of the cellar was slightly smaller than that of the mouth, and the cellar depth should be 2 to 3 m. One simpleC.korshinskiigrinder; 160 sheep and 160 goats, from which 112 sheep and 112 goats were selected for the experiment; 28 isolation fence pens[6]. TheC.korshinskiicollection site was selected in Angsu Town, Etuoke Front Banner, and the experimental site was selected in the Honghai Culture Base of Wushen Banner.

2.2 Operation method

2.2.1Grouping method. After 12 months, the selected sheep and goats were fed quantitatively, and the orthogonal experiment method[7]was used to carry out the experiment (see Table 1 for each factor and treatment). 8 goats and sheep of the same breed, similar age and normal development were selected in the experimental group and the control group according to the principle of random distribution. From early morning to evening every day, the weight of feed was the same, and the orthogonal feeding experiment was carried out after feeding in the shed for one month.

2.2.2Silage method. The experimental method was as follows：C.korshinskiisingle silage,C.korshinskiimixed silage (corn stalk with ear combined withC.korshinskii), unensiledC.korshinskii, unensiled corn stalk with ear combined withC.korshinskii.C.korshinskiisingle silage：freshC.korshinskiibranches in vegetative stage, full flowering stage, podding stage and ripening stage were crushed respectively after harvest, marked and distinguished, and then put into silage cellar after compaction.C.korshinskiimixed silage：corn stalk with ear and freshC.korshinskiibranches in vegetative stage, full flowering stage, podding stage and ripening stage were crushed at a ratio of 4：1 for ensiling and marked respectively.

Table 1 Factors and treatment

2.3 Experimental designThe experimental factors of feeding sheep withC.korshinskiisilage were as follows：C.korshinskiiin different growing season; silage mode;C.korshinskiifeed intake; corn stalk silage; hay meal intake. There were four treatment levels for each factor：vegetative stage, full flowering stage, podding stage and ripening stage.

Table orthogonal table for the experiment on daily intake of Caragana korshinskii for sheep

Table orthogonal table for the experiment on daily intake of Caragana korshinskii for goats

2.3.1Data processing. Through the orthogonal method, the test data were processed by SAS analysis software, and the error was analyzed by Excel.

3 Results and analysis

3.1 Effect of differentC.korshinskiifeed on the feeding of livestockThe results of the range analysis of the orthogonal experiment in Table 4 showed that the silage mode in the five factors had the greatest influence on the growth effect of sheep, and the extreme difference was 13.2, which was more than 2 times that of corn stalk silage and 3 times that of hay meal. Among the several factors, hay meal had the least effect on the growth of sheep, followed by corn stalk silage, and the range was only 5.7. There was no significant difference betweenC.korshinskiifeeding andC.korshinskiiharvest time.

Table 4 Range results of orthogonal test

The results of the range analysis of the orthogonal experiment in Table 4 showed that among the five factors, the feeding amount of corn kernels had the greatest effect on the growth of goats, and the fattening effect was the most significant, and the orthogonal range was 16.4; there were significant differences between the feeding amount of corn kernels andC.korshinskiiin different growth periods, silage mode,C.korshinskiifeed intake, and corn stalk silage.C.korshinskiiin different growth periods, silage mode andC.korshinskiifeed intake also had great effects on the growth of goats, but there was no significant difference among them.

3.2 Effect ofC.korshinskiifeed on the feeding of sheepFrom various factors and treatments, it can be seen that the digestible crude protein in the ensiled branches and leaves ofC.korshinskiiin flowering stage was equivalent to 2.67 kg of corn and 0.64 kg of black bean[8], so the feed had the best fattening effect on sheep, and the average monthly fat gain of each sheep was 3.58 kg. Zhang Xiaojuanetal.used column chart for analysis (Fig.1)[9], and found that the effect ofC.korshinskiisingle silage on sheep was the worst, while the effect ofC.korshinskiiand corn stalk mixed silage on sheep was very good, and the average monthly weight of each sheep increased 3.25 kg. Because of the high content of lignin and crude fiber inC.korshinskii, there was often unfinished feed when feeding sheep, and the palatability of the unensiled forage was poor[10], affecting the appetite of sheep. The effect of feeding sheep with the mixture ofC.korshinskiiand corn stalk without ensiling and fermentation was not good. In recent years, there has been a deep study on nitrogen metabolism in ruminants. Xian Lilietal.found that urea nitrogen played an important role in the process of digestion and metabolism. Urea nitrogen is an important carrier for nitrogen recycling in ruminants[11]. Many new protein nutrition systems have been proposed in many countries. The new protein system is to improve the estimated protein nutritional requirements of ruminants from the previous crude protein intake to the protein quality of the small intestine.

Note：Szp-Caragana korshinskii in different growth periods; Qzf-Caragana korshinskii silage; Wyl-Caragana korshinskii feed intake; Ymj-corn stalk silage intake; Gcf-hay meal intake.

3.3 Effect ofC.korshinskiifeed on the fattening of goats

The column chart analysis also showed thatC.korshinskiiand corn stalk mixed silage had the best effect on the growth of goats among different silage modes, and the average weight gain of each goat was 3.00 kg, but it was not significantly different from the fattening effect of unensiledC.korshinskiicombined with corn stalk with ear.

In the experiment, the effect of feeding goats withC.korshinskiisingle silage was the worst, with an average increase of 1.26 kg in weight per goat. The fattening effect ofC.korshinskiisingle silage was better than that ofC.korshinskiifor goats, and the difference between them was significant. There was a relatively small difference in the effect ofC.korshinskiifeed intake on goat fattening, but through comparative experiments, it was determined that the best feeding amount ofC.korshinskiisilage for goat fattening was 1.5 kg.

Insufficient or excessive addition ofC.korshinskiisilage affected the intake rate of goats to a certain extent. Insufficient addition led to the decrease of feed intake rate, possibly because the overall palatability of compound feed was poor, while excessive addition led to the strong taste ofC.korshinskiisilage, which affected the intake rate of goats, resulting in the decline of fattening effect. As a kind of auxiliary forage, corn stalk feed had the least effect on the fattening effect of goats, and the addition of corn stalk feed had little effect on the intake rate of goats. The effect on fattening and weight gain of goats was not obvious, and there was no significant difference among the factors. As a kind of concentrate feed for fattening of goats, corn kernels feed had a great effect on the fattening and weight gain of goats. The average weight gain of each goat at different levels of treatment was above 2.5 kg, but there was no significant difference among different treatments. Excessive addition produced surplus, the fattening effect of goats was not obvious, and it also increased the cost of feeding goats. Therefore, the best addition of corn kernels in feeding goats was 0.15 kg.

4 Conclusions and discussion

The content of crude protein, crude fat and crude fiber ofC.korshinskiiincreased in full flowering stage[12], which had the most significant effect on the fat gain of sheep, and the average monthly weight gain of each sheep was 3.58 kg, higher than that ofC.korshinskiiin podding stage, and the effect was poor in vegetative stage and ripening stage. The effect of feeding sheep withC.korshinskiisingle silage was the worst, while the effect of mixed silage ofC.korshinskiiand corn stalk with ear was very good, and the effect of feeding sheep with mixture ofC.korshinskiiand corn stalk without ensiling and fermentation was not good.

C.korshinskiifeed in ripening stage had the worst fattening effect on goats,C.korshinskiisilage in podding stage had a good fattening effect on goats, andC.korshinskiiin full flowering stage had the best fattening effect on goats[9]. The mixture ofC.korshinskiiand corn stalk had the best fattening effect on goats, the average weight gain of each goat per month was 3.00 kg, and the effect was not greatly different from the unensiledC.korshinskiiand corn stalk with ear. In the experiment, the effect of feeding goats withC.korshinskiisingle silage was the worst.