Many experiment and actual application result expressed: exiotic enzyme could improving dietary nutrients digestibility and reducing the diseases of digestive system and nutrition, and acquire effective extend in the breeding of fowl and livestock(Pettersson et al., 1989; Humski, 1991; Rotter et al., 1990). But in the wildlife, especially the breed of the Giant Pandas, research report was litter to exiotic enzyme.

Various studies on the digestibility of dietary nutrients about Giant Pandas showed no difference: the digestibility of dietary nutrients, especially in bamboo which is their major food, was very low (Zou et al., 1990; Chen et al., 1997). After investigating the death reasons of Giant Pandas, Zou Xinghuai et al., (1990) found another fact out of the scientific viewpoints. They considered that 81.5% wild and 72.7% captivity Giant Pandas died in the disease of digestive systems and nutriture, that's to say, regardless of wild or captivity Giant Panda, most of them died relating to their major food, bamboo. The bamboo containing high crude fiber carried negative effect on Giant Pandas' digestive mechanism. In order to maintaining their life and gaining nutrient they need, Giant Pandas must eat great deal of bamboo, otherwise, in their eating bamboo process, the digestive organs and mechanism were done themselves harm, often caused the digestive system diseases, for example, gastroenteritis, intestinal obstruction, volvulus, hemorrhagic tummy or intestinal bug, etc, and even death, In view of the self-contradictory fact, we used exiotic enzyme and studied its effect on the digestibility of dietary nutrients in captivity Giant Pandas in Preservation and Research Centre for the Giant Panda, Wolong, Sichuan, P R China, so as to explore the way and method of improving dietary nutrients digestibility and reducing the diseases of digestive system and nutrition.

1 Materials and methods

Eight Giant Pandas from Preservation and Research Centre for the Giant Panda, Wolong, Sichuan, P R China were used in our study. The elementary condition of them showed in tab. 1.

During the study, Giant Panda's routine diet still remained the same as before, not greatly readjusted.The raw and processed materials of diet showed in tab. 2.

The methods of confecting diet as flowing:the raw materials are weighted as the ratio in tab. 2.The green bamboo are Smashed by muller as bamboo powder.the feeds are Mixed equably and gone into water, then kneaded bread and steamed ripe.

Milk powder didn't counted into the percentage of diet and added on the side.Milk powder is dissolved by boiling water and cooled, enzyme preparation was mixed with the milk as the research project and mixed equably.After Giant Pandas ate bread, let them drink milk in a basin and normally they could drink up in ten minutes.

In light of age, the selected 8 Giant Pandas were divided into two groups.Animals in the first group(A) were younger and in their diet nutritional compound-enzyme preparation(cellulase, protease, amylase, diastatic enzyme, etc.)were added, and animals in the second group(B)were older and in their diet we took cellulase as the dominant supplement enzyme in compound-enzyme preparation.The two groups were treated by stages in the same time.That's to say, in the first stage they were all control groups(Ⅰ) and 0% compound-enzyme preparation was added in diet; in the second stage they were all treated as test groups(Ⅱ) and 0.15% compound-enzyme preparation was added in diet; in the third stage they all still treated as test group (Ⅲ) and 0.30% compound-enzyme preparation was added in diet.

During the test, feed intake and dung excretion were noted. The dung sample was collected by the method of all-collect dung. The feed or dung samples for analyzing collected by geometric method. All collected samples were weighted one by one, and taken into constant temperature blowing drying oven at 70℃ until dry, then weighted every sample air-dry weight, and kept with airproof in two-double plastic bag to analyze. In order to compare the analyzing results, all samples were analyzed on the basis of absolute dry matter.Check Giant Panda's digestibility with analysis of variance.

2 Results 2.1 Digestibility of diet dry matter

The digestibility of diet dry matter in the tested eight Giant Pandas showed in tab. 3.

2.2 Digestibility of diet main nutrients

The digestibility of main nutrients in diet in the tested eight Giant Pandas showed in tab. 4.

2.3 Significance test among the digestibilities of main nutrients in diet

Results that significance test among the digestibilities of main nutrients in diet in the tested eight Giant Pandas showed in tab. 5.

Significance test among the digestibilities of main nutrients in diet showed that: in test A, the CP digestibility of giant pandas in test Ⅲ was higher than that in control testⅠ, and the crude fat digestibility in test Ⅲ was higher than in testⅡand controlⅠ, But there were no significant difference among the groups in the digestibility of dry matter and carbohydrate in diet; in test B, the CP digestibility of giant pandas in test Ⅲ was higher than in control groupⅠ, and the crude fat digestibility in test Ⅲ was higher than controlⅠ, But there were no significant difference among the groups in the digestibility of dry matter and carbohydrate in diet.

2.4 Significance test among the digestibilities of amino acids in diet

Results of significance test among the digestibilities of amino acids in diet in the tested eight Giant Pandas showed in tab. 6.

Significance test among the digestibilities of amino acids in diet showed that: in test A, the Thr, Ser, Val digestibility of Giant Pandas in test Ⅲ was higher than that in control testⅠ, the Asp, Ile, Phe, His digestibility in test Ⅲ was higher than that in testⅡ and controlⅠ, the Lys digestibility in test Ⅲ was higher than that in testⅡ. But there were no significant difference among the groups in the digestibility of Glu, Gly, Ala, Met, Leu, Tyr, Arg; in test B, the Thr, Glu, Met, Ile, Lys, Arg, Leu digestibility of Giant Pandas in test Ⅲ was higher than that in control testⅠ, the Thr, Ser, Gly, His digestibility in test Ⅲ was higher than that in testⅡand controlⅠ, and Thr, Ser digestibility in testⅡ was higher than that in controlⅠ, But there were no significant difference among the groups in the digestibility of Asp, Ala.

Significance test among the digestibilities of total amino acids in diet showed that: in test A, the digestibility of test Ⅲ was higher than that of testⅡ, but no difference with controlⅠ; in test B, the digestibility of test Ⅲ was higher then that of controlⅠ, but no difference with test Ⅱ.

2.5 Significance test among the digestibilities of cellulose, hemicellulose and NDF, ADF in diet

The results that significance test among the digestibilities of cellulose, hemicellulose and NDF, ADF in diet in the tested eight giant pandas showed in tab. 7.

Significance test among the digestibilities of cellulose, hemicellulose and NDF, ADF in diet showed that: in test A, the Cellulose, NDF, ADF digestibility of giant pandas in test Ⅲ was higher than in testⅡand controlⅠ, But there were no significant difference among the groups in the digestibility of Hemicellulose; in test A, the Cellulose, NDF, ADF digestibility of giant pandas in test Ⅲ was higher than in testⅡand controlⅠ, and testⅡ was higher than in and controlⅠ, the hemicellulose digestibility in test Ⅲ was higher than that in controlⅠ.

3 Discussion 3.1 Effect of adding enzyme preparation on the digestibility of CP and CF

Adding enzyme preparation in diet would improve captive giant panda's digestive mechanism. This displayed that the feedstuff digestibilities of CP and CF were significantly increased when adding nutritional compound-enzyme or cellulose compound-enzyme preparation in giant panda's diet. In test A adding nutritional compound-enzyme preparation, the digestibility of CP and CF in diet were increased by 13% and 14% compared with the control respectively and the statistical test was significant. The results meant the exotic enzyme played an important improving role on giant panda's digestibility. In test B adding cellulose compound-enzyme preparation, the digestibility of CP in diet was increased by 5% compared with the control, then the digestibility of CF when adding 0.15% cellulose compound-enzyme preparation in diet was better than that of adding 0.30% preparation, but it was not certain whether this results was true or not.

3.2 Effect of adding enzyme preparation on the digestibility of amino acids

Giant pandas could increased their digestive ability on amino acids when adding any of the two enzyme preparation in diet. The effect of adding the high level (0.30%) compound-enzyme preparation in diet was better than that of adding low level (0.15%), especially better than that of no addition.

3.3 Effect of adding enzyme preparation on the digestibility of cellulose

In this study, adding either nutritional compound-enzyme or cellulose compound-enzyme preparation in diet, especially adding cellulose compound-enzyme, the effect on the digestibility of cellulose and so on was very significant, and the digestibility of cellulose and so on was improved along with the increasing of enzyme adding level.

This study also indicated that it was extremely deficient in cellulose compound-enzyme in Giant Panda's body. Giant Pandas usually eat bamboo containing great deal of crude fiber and the crude fiber was very difficult to digest and absorb in their body. There was availability to improve the digestive function and increase the digestibility of crude fiber in diet of Giant Pandas.

The technical methods of this study could be extensive applied to feeding practice of migrating protective Giant Panda.

4 Brief summary

It was absent of cellulose enzyme in Giant Panda's alimentary canal and this induced the digestibility of crude fiber in bamboo was very low. Thus there would be a distinct effect when adding nutritional or cellulose compound-enzyme preparation in Giant Panda's diet. The technical methods of this study could be directly applied to feeding practice of Giant Panda.

There was an excellent assimilation effect on CP, CF, amino acids when adding enzyme preparation and the digestibility of them increased significately.

Using enzyme preparation in migrating protective practice of giant panda was feasible because it was the substance of protein and had no harm to Giant Panda's body.

In this study only two grads of adding enzyme preparation was projected, and the tend of digestibility of dietary nutrients was the more adding enzyme preparation the better digesting nutrients in diet, but the exact or best enzyme dosage adding in diet awaited further study.