The Influence Of LDA By Surgery Upon Goat's Gastric Function

As the dairy industry and milk yield developing dramatically, the occurrence rate of displacement of the abomasums(DA) rises very rapidly, and making great damage to the dairy industry. DA includes left displacement of abomasums(LDA) and right displacement of the abomasums(RDA). But at present the etiology and pathogenesis of DA haven't be explained consistently by people. Inorder to study the influences of LDA upon dairy cow, we had created animal model of LDA by surgery, Man-made LDA, and data were collected from all operated goats and control group goats.1. Nine health goats were randomly divided into left coxa nodus displacement of abomasums(LCDA) group, paunch bottom displacement of abomasums(PDA) group and control group. LCDA group goats were made surgery operation of fixing the abomasums between the rumen and ventro-wall after the abomasums round the rumen and was towed to left coxa nodus level, PDA group goats were made surgery operation of fixing the abomasums under the rumen bottom, and control group goats were only accepted the abdominaltomy. Three group goats were all fitted with permanent rumen fistulae and abomasal intubate to collect the contention of rumen and abomasums at scheduled time, and the article mostly observed volatile fatty acids(VFA), the pH values in rumen fluid and abomasal fluid and serum gastrin(GS). After operation, all goats exhibited the typical symptom of LDA cow, that's to say the Man-made LDA is successful.2.This study indicated that: Man-made LDA can reduce the digestive and metabolic ability of rumen, and drop the ability of rumen microorganism ferment, LCDA group is significantly severity than PDA group, and PDA group is significantly severity than control group. Along with extending of the course of LDA, the rumen microorganism ferment ability depress significantly. Man-made LDA can cause the constitute proportion of volatile fatty acids(VFA) in rumen to change, that is to say increase the proportion acetic acid and propionate.3. This study indicated that: Man-made LDA can increase gross contentation of VFA. As a result of operation stress, the VFA contentation in abomasums of PDA group is higher than LCDA group at the period of 5th day to 12th day after surgery operation. Since the 12th day after Man-made LDA surgery operation, the VFA contentation in abomasums of all Man-made LDA goats exhibited a downtrend, but the VFA contentation of LCDA group was more than PDA group, and the style of ferment in abomasums was altered. The gas amount enhancing and abomasums movement ability declining are the key factor to DA.4. This study indicated that: Man-made LDA can reduce the pH value in rumen and in abomasums, and the decrease degree is related to the DA style, LCDA group was more than LPDA group. But the pH value altering trends is more complex in LCDA group. Man-made LDA can increase contentation of GS in serum especially 7th day after Man-made LDA surgery operation as the increasing of VFA, and the GS contention is related to the style and course of DA.