Displacement of Abomasum and Its Performance on Clinical Serum Biochemistry in Dairy Cows in Taiwan

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1 ep~1#j:\l~~t.j Chin Soc Vet Sci 27 (3): ,2001 Displacement of Abomasum and Its Performance on Clinical Serum Biochemistry in Dairy Cows in Taiwan *Shih-Te CHUANG, Jacky Peng-Wen CHAN, Pan-Chen L1U, Cicero Lee-Tian Chang, Chaun-Loong TSANG, Chi-Liang MAO, and Hang-Poung FUNG Department of Veterinary Medicine, National Chung-Hsing University, Taichung, Taiwan 402, ROC (Received: October 5, Accepted: April 17, ) ABSTRACT Displacement of abomasum is now recognized as one of the most commonly encountered metabolic diseases in Taiwan. The purpose of this study was to estimate serum electrolyte and mineral concentrations in cows diagnosed with displacement of abomasum, as well as to evaluate the recovery rate of this disease after surgery. Fifty cows were diagnosed with left displacement of abomasum and 7 with right displacement of abomasum. These cows were 3.83± 1.14 years old and experienced an average of 2.12±0.96 parturitions, and the percentages of the operations (right paralumbar omentopexy) performed on cows with first calving, and during subsequent 2 nd and 3,d lactations were 28.1% (16/57), 40.4% (23/57), and 26.3% (15/57), respectively. There were 49 cows affected with displacement of abomasum in the first lactation month after calving. More than half of the surgeries (32 or 56. 1%) was performed during the summermonths (June, July, and August). Of the total 57 cows diagnosed with LDA or RDA, 45 (78.9%) showed signs of ketosis, displaying significant Iy lower concentrat ions of Ca2+, Mg 2+, K+, and CI- (P<O.01), when compared with healthy cows from the same herds. The mean concentrations of Pz- and Na+ were not different for cases and controls (P>0.05) in this study. We concluded that the right flank omentopexy is a well-accepted technique to treat displacement of abomasum, and hypocalcemia could increase the occurrence of this disease in early lactation. [. ChuangST, ChanJackyPW, LiuPC, Chang Cicero LT, TsangCL, MaoCL, and FungHP. Displacement of abomasum and its performance on clinical serum biochemistry in dairy cows in Taiwan. J Chin Soc Vet Sci 27 (3): , Corresponding author TEL: FAX: , stchuang@ dragon. nchu. edu. tw 1 Key words: Abomasum, Displacement, Serum biochemistry, Dairy cows INTRODUCTION The abomasum is the fourth compartment of the ruminant stomach. Its function consists of further digestion of partially degraded substrates from the rumen, reticulum, and omasum, and secretion of pepsinogen and hydrochloric acid. The abomasal ph is maintained at approximately 3.0 under normal conditions [10]. Abomasal disorders occur frequently in clinical bovine practice. Displacements, dilations, and volvulus are now recognized as one of the most commonly encountered metabolic diseases and gastrointestinal problems in modern dairy practice in Taiwan. The displacement can be on the left side (left displacement of abomasums, LDA) or the right

2 Displacement of Abomasum and Its Performance on Clinical Serum Biochemistry in Dairy Cows in Taiwan 176 side (right displacement of abomasums, RDA). Since LDA was first reported in the early 1950s [1,11], its prevalence in well-managed dairy herds varies from % and may be considerably greater in some herds [21,27]. Several techniques have been used to treat LDA and RDA, and we have had good results with an omentopexy followed by replacement through a right paralumbar incision. There has been a long-standing interest in studying the relationship between hypocalcemia and displacement of abomasum (DA). Abomasal motility has been observed to decrease with hypocalcemia in cows at postpartum. The objectives of this research are to study the recovery rate of DA after using a right paralumbar surgical approach, as well as to evaluate serum electrolyte and mineral concentrations at the time of on-farm diagnosis of DA, in the effort to estimate the possibility and potential of using calcium salts in the prevention and treatment of DA. MATERIALS AND METHODS Patients This study used a total of 57 dairy cows from 12 Taiwan dairy farms suffering from LDA or RDA and were admitted to the Veterinary Teaching Hospital, College of Veterinary Medicine at National Chung Hsing University during a 6-year period ( ). The cattle ranged in age from 2-8 years. Physical examinations, which included monitoring the rectal temperature, heart rate, respiratory rate, and rumen motility, were performed prior to treatment and clinical findings and treatment results were recorded. Venous blood samples were collected from the coccygeal vein for blood biochemical analysis, which included electrolyte concentrations (Ci+, p 2 -, Mg 2 +, Na +, K'. cr: analyzed using the 550 Express Plus Clinical Chemistry Analyzer (Ciba-Corning Compo USA). Urine samples were collected to check for ketone body using the Chernstrip" test. Each cow was clinically examined 3 times after surgery, to check for recurrence of abomasal displacement and to monitor oveall recovery. The first examination was performed 3-7 days after surgery, the second follow-up examination was days after surgery, and the third was 4 weeks after surgery. Control group Control cows were selected by asking herd owners to identify a healthy cow having the closest calving date as possible to the cow diagnosed with DA in the same lactation period. Surgical method In our study, the surgical procedure was performed with the cow standing. The right paralumbar area was clipped and prepared surgically. An inverted L-block of local anesthesia with 2 % Lidocaine was administered. The abdomen was entered through a 15-cm vertical incision in the right paralumbar fossa starting 10 em ventral to the transverse processes of the lumbar vertebrae. In case of LDA, the surgeon passed his left arm to the left side of the rumen to palpate the abomasum usually distended with gas. The gas then was released using a 16-gauge needle with sterile tubing attached and inserted into the abomasal wall. After completely releasing the gas, the needle was carefully withdrawn to prevent contamination to other organs. The abomasum was then easier to replace. It was helpful to place the left hand and forearm on top of the displaced abomasum and sweep downward and around the ventral part of the abdomen to its normal position. If the rumen was large and too heavy, it was helpful to start sweeping the abomasum downward at first, and then lift the posterior ventral blind sac of the rumen with the inside of the elbow to raise the rumen, finally pulling the abomasum to the right along the ventral abdominal wall [13]. The superficial layer of greater omentum, observed through the abdominal incision, was grasped and gently retracted dorsally and caudally to pull out through the incision. The pylorus was visible and recognized by its typical shape and color. The greater omentum can be differentiated from the lesser omentum by its thickness, consistency and color. Depending on the amount of fatty tissue present, the greater omentum was usually light yellow in color, having a fleshy and fatty consistency and much thicker than the lesser omentum [4]. Simple interrupted suture was placed through the peritoneum and transverse abdominal muscle and through both layers of the

3 177 Shih-Te CHUANG et al. fold of omentum with nu~b er 3 nonabsorb able sy n th etic sut ure mat eri al, leaving th e omentum incor pora ted into th e sut ure line in th e vent ra l twothirds of the incision. The intern al and ex ternal abdom inal oblique muscle layers and t he sk in were closed as in a routine flank laparot om y [42]. T he wound was finally spraye d with iodine solut ion and Gusanex" to prevent infection and against flies. Aftercare Antibiot ics were not adm iniste red posto pera tively unless indicate d by pro longe d surge ry, overt conta mination, or elevated rectal temperat ure du e to metri tis or mastitis. Cows we re intrave nously administered 100 ml 50% Calcium glucona te, ml 50% Glucose, B-com plex and rumenal st imu lants, subseque ntly for 3 days. Cows wit h sings of deh ydration or emp ty rume n were adm inistered L of luk ewarm wa te r, 150 gm NaCI an d gm KCI was administered by sto mac h tub e immediately afte r surge ry. T he cows were give n access to hay and water imm ediat ely after surgery, an d th e amo unt of feed concent ra tes was increased daily until cows showe d clini cally normal appe tite 9-10 days post operatively. Skin sutures were rout inely removed on day postoperatively. RESULTS T here were 50 ( 87.7%) diagn osed cases of LDA and 7 ( 12. 3% ) diagn osed cases of RDA. Forty-seven cows wit h LDA recovered and resumed satisfactory milk pro duct ion post operatively. Three cows with LDA had recurrence of the same disease after th e first surge ry, and a second ope ration was performed on tw o of th ese cows, while t he thi rd cow was culled due to poor ph ysical cond ition. There was only one cow that had a recur ren ce of LDA soon afte r she calved aga in 14 mont hs after the first surge ry. Among the 7 cows with RDA, 3 cows contin ued to disp lay poor digest ive function postoperati vely and we re subseq uen tly slaughtered. The affected cows we re 3.83 ± yea rs old and ex perienced an ave rage of ± par tur i tions (Figs. 1 and 2). Of th e surgica l treatments, 28.1 % (16/57) of the surgeries were perform ed on heifers wit h first calving, % (2 3/57) on cows duri ng 2 nd lact ation, and % (15 /57) on cows during 3,d lactati on. T he re was only one cow th at was in 4 th, and 2 cows in 5 th lact ati on. Of th e surgeries performed on cows afte r parturition, % (37/ 57) of th e cases wer e less th an 2 wee ks post parturition. A total of 49 cows (86%) were affec t ed with DA dur ing th e first month of lactation afte r calving. T he distribution of th e 57 cases with different post partum tim es is represented graphically in Figure 3. Mor e tha n half of th e surgical cases ( 32/ 57, 56. 1%) was performed during summer months (J une, July, and August ). Seve nteen ( 29.8%) of th e cases we re diagnosed during Se pte mber, Octo ber, and Novem ber (Fig. 4). Of th e 7 cows diagn osed with RDA, two were pregnant, and th e disease was suspec ted to be conce rne d with foot treatment, since both cows show ed clinical sign of DA imm ediat ely afte r foot treatment. Of th e 57 cows diagn osed wi th LDA or RDA, 45 ( %) cows also had ketosis. T o recogni ze seru m electrolytes and mineral concentra tions in cows wit h DA, th e mean diff eren ces between affect ed and con tro l cows are sh own in T abl e 1. Cows wit h LDA or RDA had significantl y low er conce nt rations of Ca 2 ', Mg H, K ', and CI- ( P < 0.01 ) wh en compa red with healthy cows from th e same herd s. The mean p 2- and Na' conce ntra tion was not different for affected cows and contro ls (P > 0.05). T able 2 shows th e mean and st andard deviations for t he serum che m istry values measured. The mean differe nces of tot al seru m Ca 2 ' concentr at ions bet ween affected cows and th e control group indicat ed that 96.5 % of affected cows (55 / 57) had conce ntrations below th e lower limit of th e laborator y refe rence range ( mg/dl), and 26.7% (12/ 45) of matched control cows had values below nor mal. More tha n half of the affecte d cows (32/ 57, 56.1 %) showe d lower th an normal serum Mg 2 ' concentrations when compared with 11.1 % (5/ 45) of matched control cows wit h values below normal. T he other values of r-: and Na + in affected and unaffected cows we re in th e norma l range for this study.

4 Displacement of Abomasum and Its Perform ance on Clinical Serum Biochemistry in Dair y Cows in T aiwan % 3.6% DA. 26.3% o under older than.~ I 80% 60% D higher than normal normal o lower than normal 40% 20% Ca P Mg Na K CI Fig. 1 Percent age of age (years old) in cow s af - fected with DA. Fig. 5 Resul t of serum mineral and elec trolyte for cows wi th a bomasa l d isplacement. 1ol~ 1 ill 2 DISCUSSION Fig. 2 Percentage of parturit ion t imes in cows affec ted with DA /' 10 / o 1 wk 2 wks 3 wks 4 wks 1-2 longer mths than 2 mths Fig. 3 Rela t ionshi p between occurence of DA and post pa rtum per iod summer The abomasum is cra nially attached to the o masum and to th e reticulum through a band of smooth muscl e. This attachment limits its mob ility. How ever, th e caudal attachment to th e greater ome n tum provides gr eater mobility, allowing displacement of abomasum in different dir ections. Left displacement is th e most common of th e abomasal twi st s, constituting 87.5 % in our study, and 85 % to 95.8 % in other studies [10,40]. It is gener ally accepted that atony is th e pr ecursor of displa cement [37]. Factors influ encing th e incid ence of displ acement include total size of th e abdominal cavity, stage of gestation, and perhaps exte rn al factors such as transportation, exercise, prior surgery, and stress [3]. Dairy cattle are at higher risk of developing LOA than beef cattle, but th ere seems to be no effect of milk yield on th e risk of abom asal displacem ent [ 15]. Alt hough LOA was diagnosed to be more commonly in cows older th an 2 years, and a great er risk in cows aged 4 to 7 years [5], it has been diagn osed in a 9-w eek-old calf [ 9]. In our study, th e diseased cows wer e 3.83 ± I. 14 years old and experienced an average of ± 0.96 parturitions, whi ch is younger than affec ted cows in other st udies. Of th e cows affec ted with OA, 28.1 % were heifers with first calving. We considered th at th e condition of feeding and man agem ent of th e heifers in T aiw an should be better cont rolled. In ot he r published references, Gu ernsey cattle were significantly at mor e risk of developing LOA th an Holst ein cattle, and female cattle were also at high er risk of developing LOA th an were male cattle [ 43 ]. In th eir report, % of th e cases were diautumn Fig. 4 Rel at ionshi p between occurence of DA and season.

5 179 Shih-Te CHUANG et at. Table 1. Results of serum biochemistry analysis for cows with DA and cantrol cows. Cases (n = 57) Control(n = 45) Referenced (X ± s) (X ± s) value' Ca 2+ (mg/dl) 8.27 ± ± r-: (mg/dl) 6.12 ± ± Mg 2+ (mg/dl) ± ± Na + (mmoill) ± ± K' (rnmol/l) 3.85 ± ± Cl (rnmol/l) 95.2 ± ± ": Smith BP. In:Large animal internal medicine (1996) Table 2. Statistical analysis of the effect of serum electrolyte and mineral concentrations. Mean 95% confidence interval Difference of difference Lower bound Upper bound standard error ci p z Mg Na K Cl agnosed within 2 weeks of parturition and 80.2 % of cases within 1 month of parturition. In our study, 86.0% (49/57) of the cows with displacement of abomasum were diagnosed during the first month of lactation. with results of other reports, This finding generally agreed which showed that LDA was associated with parturition, and about 80% of the LDA cases were diagnosed within 30 days after parturition, and 91% less than 6 weeks after parturition [22,29,44]. In our study, more than a half of thc surgeries (32/57 or 56.1 %) were performed during summer months (June, July and August). This seasonal variation was probably due to the higher temperatures and greater rainfall on Taiwan during the summer months, which caused cows to be more prone to stress at the time of parturition. This point was similar to Petty's study [25] conducted in southern California, in which he indicated that 78% (143/183) of cases occurred during the season of greatest rainfall. Constable et al. reported a seasonal variation in the incidence of LDA in which the peak number of cases developed in spring and the lowest number developed in autumn [5]. Al though seasonal changes may playa role in inducing abomasal atony, the exact cause of the seasonal variation is unknown. Recently epidemiological studies based on large sample sizes failed to detect an association between level of milk production and LDA, although early studies indicated that a high level of milk production predisposed cattle to LDA [5,6,22]. Nutrition is the management practice that potentially has the greatest impact on incidence of LDA, because low crude-fiber concentration and rapid increase in concentrate intake are considered major predisposing factors for abomasal displacement [6,29]. The evidence suggests that the conditions for atony develop during the drying off period, when concentrate feeding is often

6 Displacement of Abomasum and Its Performance on Clinical Serum Biochemistry in Dairy Cows in Taiwan 180 abruptly withdrawn and glandular activity of the abomasum is reduced to its lowest level. This period, although valuable in providing rest in a physiological sense, can also be stressful in its interruption of routine, e. g., withholding food and a single milking [37]. Upon analyzing large amounts of data, Constable et al. [5] hypothesized that normal rumen volume constitutes a moderately effective barrier against LDA, and the high incidence of LDA in lactating dairy cattle results from the additive effects of decreased rumen volume, increased abdominal void immediately after parturition, and increased exposure to factors that induce abomasal atony. Although there is not enough data in this study to indicate that post parturient mastitis and metritis predispose cattle to LDA, we considered that the concurrent diseases may be accompanied by alkalemia and high plasma concentration of endotoxin, histamine, and epinephrine, which can induce abomasal displacement caused by atony. Mechanical effects in the abomasal displacement, the changes in intra-abdominal pressures and the fetal position during late pregnancy, may contribute to abomasal displacement, however, the fact that the beef cows, subjected to the same intra-abdominal changes retains normal abomasal function, suggests that these effects are secondary [37]. Clinically, cattle with LDA or RDA usually show a reduction in appetite accompanied by a progressive decrease in milk production. Often the patients show a preferential loss of appetite for grain while still consuming forages. Ketosis may develop as a secondary problem. Feces are often softer than normal. Rectal temperature are normal, as the pulse and respiratory rates. A cow with LDA can be clinically normal for one and a half years [17]. Simultaneous auscultation and percussion of the left flank should be done in suspected cases to elicit the characteristic metallic "ping" voice. In some cattle, ribs may appear elevated in large displacements. The differential diagnosis of LDA includes other causes of left-sided pings, such as ruminal tympany and pneumoperitoneum. But the location and intensity of the ping can be useful in differentiation. Pings of pneumoperitoneum nature are located dorsally under the transverse vertebral apophysis. The pings usually are less musical, of a lower pitch, and should extend to the right side as well. A rumen ping can cover a large area and can sometimes be heard when percussion of the shaft of the ileum or the transverse apophysis is performed [10]. Techniques used to treat LDA and RDA vary from medical management to surgical abomasal fixation via laparotomy. Casting and rolling for LDA correction is the most common form of non-surgical treatment. The inherent limitation of the rolling technique is failure to stabilize the abomasum, leading to a recurrence rate of approximately 75 %, and even causing uterine torsion and abomasal volvulus [35]. It is very important to correct the displacement of abomasum and fix it on its proper position. The permanent attachment of abomasum in its correct position is usually created either by suturing the abomasum (abomasopexy), or the greater o mentum (omentopexy) to the abdominal wall [ 10,31,42]. The paramedian approaches provide an excellent attachment (abomasopexy) with minimal invasion of the abdomen. The ability to explore extensively in the abdomen, however, is severely restricted. The closed suturing technique (blind stitch) was introduced in the early 1970s, but it has the potential to cause complications [31,39]. The bar suture (toggle) technique introduced in 1982 by Grymer and Sterner offers some advantages over the blind stitch [16]. Although some authors stated the success rates of closed suturing and laparotomy were equally satisfactory, Rutgers and van der Velden [31] suggested that closed suturing was not an acceptable alternative for surgical treatment by laparotomy, because it is impossible to determine which abdominal structures are being sutured and this method implied an increased risk of complication. The greatest advantage of surgical abomasopexy via laparotomy is the opportunity for the surgeon to thoroughly explore the abdomen for possible complicating factors, such as perforating abomasal ulcers and associated adhesions [18]. The left flank abomasopexy is used to visualize a portion of the abomasum in the standing patient. It is a good approach in cows with suspected abomasal adhesions and in cows in late gestation (later than 7 months). But this approach cannot be used prophy-

7 181 Shih-Te CHUANG et al. lactically and requires more than one person to complete the procedure and the surgeon must also avoid trapping omentum or bowel under the suture. The right flank abomasopexy is a well-accepted technique but relies heavily on the strength of the omentum to hold the abomasum in place. This is a one-person technique and allows the surgeon the most complete exploration of the abdomen [10]. Kelton [18] compared one group using bar suture abomasopexy technique to the other group using the right paramedian abomasopexy via laparotomy. There was found to be no significant difference in cows returning to normal milk production, returning to normal feed intake, mortality, culling rate, tissue reaction at the surgical site, or redisplacement up to 60 days into the subsequent lactation. In Gabel and Heath's study [13], 86% (126/ 147) of cows with LDA had healthy recoveries after surgery, while 5 were slaughtered due to unsatisfactory results. In 3 of these 5 cows, there was redisplacement of the abomasum to the left side. The other cows were slaughtered because of other reproductive disorders or because postsurgical information could not be obtained. Studies reported high recovery rates after surgery. Lowe et al. [19] reported a recovery rate of 94 % in 82 cows treated by abomasopexy with an incision from the xyphoid process to the umbilicus. Surgical fixation via laparotomy has been shown to prevent recurrence of abomasal displacement in 83.5 % to 95 % of cases [25,26,28]. The recurrence rate was 3.45 % (2/ 59) in Kelton's [18] study and 5.3% (3/57) in ours. The redisplacement of the abomasum was probably due to too far dorsal and caudal point of o mental fixation to the pyloric part of the abomasum [13], which caused stretching of the omentopexy [2], disruption of the omentopexy, and avulsion of the omentum from the abomasum [30,41,43]. The postsurgical death rate was 8.4% (12/143) [25] compared with Wallace's [43] report of 13 % (17/ 131) for , 5.5% (5/91) for , and 12.2% (11/90) for Petty [25] reported that cows with LDA had no prolonged period of open stage, and within 30 days postsurgically, most of the cows had near "normal" daily milk production, in contrast to Robertson's report, that many cows with LDA have decreased fertility [29]. Cows experienced hypocalcemia near the time of calving were found to be at increased risk of subsequent LDA [23]. Hypocalcemia could affect the incidence of DA directly by effects on abomasal motility or indirectly by increasing the occurrence of other diseases in early lactation. In our study, we found that the serum values of Ca 2+, Mg 2+, K + and Cl " in cows affected with DA were below the normal range compared with control cows. Our results demonstrated that cows diagnosed with DA had a significantly lower total serum Ca 2+ concentration than unaffected cows in the same herd. A familiar result was also found by other study [8]. Hypocalcemia and other clinical chemical abnormalities concurrent with DA were described in other references. Blood chemistry evaluation of cows with LDA revealed decreases in calcium [10,24,28,34,43], potassium [10,24,34], chloride [10,34], and magnesium [24], with metabolic alkalosis recorded on certain days and metabolic acidosis recorded occasionally [24]. Alkalosis occurring in cows suffering from DA was thought to be due to an absence of abomasum fluid passing through to the intestine, which contained a high concentration of H+. In our study, we did not have additional information about the alkalosis situation of cows because all the surgeries were performed on the premise of farms, and not in our hospital. As such, accurate results could not be obtained when we sent samples to a laboratory. In contrast to previous hospital-based investigations, there was study in which an increased serum magnesium concentration was found [28]. Taguchi [38] stated that hypochloremic alkalosis was observed in cows with LDA only when the cows were severely dehydrated, but cows with RDA revealed less electrolytes and acid-base abnormalities despite the increase in the dehydration score. Decreased plasma concentrations of Cl" and K + were attributed primarily to sequestration of gastric contents, anorexia, and hyperbicarbonatemia [34]. Total body depletion of Na +, decreased intake, loss of Na + through alimentary secretions, and urinary excretion of sodium all contributed to hyponatremia [20,34]. The hypokalemia condition in cows was

8 Displacement of Abomasum and Its Performance on Clinical Serum Biochemistry in Dairy Cows in Taiwan 182 probably a result of several factors, including anorexia, intracellular movement associated with metabolic alkalosis, and loss through the urine and the abomasal effluent [12]. Ketosis is always diagnosed in cows with DA because of poor daily intake. In our study, 78.6 % of cows with LDA or RDA were diagnosed with ketosis. This result was similar to Kelton's report of % (41/59) [18], and was consistent with Curtis' [7] result that cows with uncomplicated ketosis are at increased risk of LDA, and cows with LDA are likely to develop clinical ketosis. Grohn et al. [15) also indicated that cows with disorders of the abomasum had higher risks of developing ketosis. Hypocalcemia prevents the secretion of insulin, which hinders tissue uptake of glucose. Reduced glucose uptake would exacerbate lipid mobilization at calving, thus increasing the risk of ketosis [14). Because abomasal displacement is a multifactorial syndrome, prevention involves control of known predisposing factors. Nutritional management is among the most influential factors. Transition to production diets should be gradual to reduce chances of indigestion (lead feeding). According to the rumen barrier hypothesis, it is indicated that a potential method for decreasing the incidence of LDA in dairy cattle may be to ensure adequate rumen volume during the post parturient period. This can be achieved by feeding a high-roughage diet because ruminal volume increases with increased roughage intake [5,6). The factors influencing hypocalcemia around the time of parturition should be reviewed and corrected as needed. High-concentrate rations need to be corrected and managed. Any inflammatory disease of the periparturient cow (i. e., metritis, mastitis) should be appropriately treated [10). It is also suggested that feeding higher intakes of protein and energy during the last 3 weeks of the dry period may reduce the incidence of metabolic and reproductive disorders. REFERENCES 1. Begg H. Diseases of the stomach of the adult ruminant. Vet Rec. 62: , Blikslager AT, Anderson KL, Bristol DG, Fubini SL, Anderson DE. Repeat laparotomy for gastrointestinal disorders in cattle: 57 cases ( ). J Am Vet Med Assoc , Breukink HJ. Abomasal displacement etiology, pathogenesis, treatment and prevention. Bovine Pract 26: , BucknerR. Surgical correction of left displaced abomasum in cattle. Vet Rec 136: , Constable PO, Miller GY, Hoffsis, GF, Hull BL, Rings OM. Risk factors for abomasal volvulus and left abomasal displacement in cattle. Am J Vet Res 53: , Coppock CEo Displacement abomasum in dairy cattle: etiological factors. J Dairy Sci 57: , Curtis DR, Erb HN, Sniffen CJ, Smith RD, KronfeldOS. Path analysis of dry period nutrition, postpartum metabolic and reproductive disorders, and mastitis in Holstein cows. J Dairy Sci 68: , Delgado-Lecaroz R, Warnick, LD, Guard, CL, Smith MC, Barry DA. Cross-sectional study of the association of abomasal displacement or volvulus with serum electrolyte and mineral concentrationsin dairy cows. Can Vet J 41: , Dennis R. Abomasal displacement and tympany in a nineweek-old calf. Vet Rec 114: , Fecteau G, Sattler N, RingsOM. Abomasal physiology, and dilation, displacement, and volvulus. In: Howard JL, Smith RA., ed. Current veterinary theraph 4: Food animal Practice. WB Saunders Co., Philadelphia , Ford EJH. A case of displacement of the bovine abomasums. Vet Rec. 62: , Fubini SL, Grohn YT, Smith OF. Right displacement of the abomasum and abomasal volvulus in dairy cows: 458 cases ( ). J Am Vet Med Assoc 198: , Gabel AA, HeathRB. Correction and right-sided omentopexy in treatment of left-sided displacement of the abomasum in dairy cattle. J Am Vet Med Assoc 155: , Goff JP, Horst RL. Physiological changes at parturition and their relationship to metabolic disorders. J Dairy Sci 80: , Grohn YT, Eicker SW, Hertl JA. The association between previous 305-day milk yield and disease in New York state dairy cows. J Dairy Sci 78: , Grymer J, Sterner KE. Percutaneous fixation of the left displaced abomasums, using a bar suture. J Am Vet Med Assoc 180: , Ingling AL, Albert, TF, Schueler RL. Left displacement of the abomasum in a clinically normal cow. J Am Vet Med Assoc 166: , kelton OF, Garcia J, Guard CL, Dinsmore RP, Powers PM, Smith MC, Stehman S, Ralston N, White ME. Bar suture (toggle pin) vs open surgical abomasopexy for treatment of left displaced abomasums in dairy cattle. J Am Vet Med Assoc 195: , 1988.

9 183 Shih-Te CHUANG et al. 19. Lowe JE, Loomis WK, Kramer LL. Abomasopexy for repair of left abomasal displacement in dairy cattle. J Am Vet Med Assoc Lunn DP, McGuirk SH, Smith OF. Renal metabolic acid and electrolyte excretion in an experimental model of hypochloremic metabolic alkalosis in sheep. Am J Vet Res 51: , Markusfeld O. Periparturient traits in seven high producing dairy herds. Incidence rates, association with parity, and interrelationship among traits. J Dairy Sci 70: , Martin W. Left abomasal displacement: an epidemiological study. Can Vet J 13: 61-68, Massey CD, Wang C, Donovan GA, Beede OK. Hypocalcemia at parturition as a risk factor for left displacement of the abomasum in dairy cows. J Am Vet Med. Assoc. 203: , Ozkan K, Poulsen JSD. Changes in ionized calcium content and related clinical chemical parameters in cases of left-sided abomasal displacement. Nord Vet Med 38: , Petty RD. Surgical correction of left displaced abomasums in cattle: a retrospective study of 143 cases. J Am Vet Med Assoc 178: , Pinsent PHJN, Neal PA, Richie HE. Displacement of the bovine abomasums: a review of 80 clinical cases. Vet Rec 73: , RadostitsOM, Gay CC, Blood DC, Hinchcliff KW. Diseases of the abomasums of cattle. In: Radostits OM, ed. Veterinary medicine. 9th. Ed. WB Saunders Co, Philadelphia, , Robertson JM. Left displacement of the bovine abomasum: laboratory findings. J Am Vet Med Assoc 149: Robertson JM. Left displacement of the bovine abomasum: epizootiologic factors. Am J Vet Res 29: , Robertson JM, Boucher WB. Treatment of left displacement of the bovine abomasums. J Am Vet Med Assoc. 149: , Rutgers LJE, Van der Velden MA. Complications following the use of the closed suturing technique for correction of left abomasal displacement in cows. Vet Rec 113: , Simpson OF, Erb HN, Smith OF. Base excess as a prognostic and diagnostic indicator in cows with abomasal volvulus or right displacement of the abomasum. Am J Vet Res 46: , Smith OF. Right sided torsion of the abomasum in dairy cows: classification of severity and valuation of outcome. J Am Vet Med Assoc 173: , Smith OF, Lunn DP, Robinson GM. Experimental model of hypochloremic metabolic alkalosis caused by diversion of abomasal outflow in sheep. Am J Vet Res. 51: , St. Jean G, Constable PO, Huli BL, Rings OM. Abomasal volvulus in cattle following correction of left displacement by casting and rolling. Cornell Vet 79: , Sterner KE, Grymer J. Closed suturing technique using a bar-suture for correction of left displaced abomasums-a review of 100 cases. Bovine Pract 17: 80-84, Sutherland FR. Abomasal displacement in a changing husbandry and its treatment. Vet Rec 115: 33-35, Taguchi K. Relationship between degree of dehydration and serum electrolytes and acid-base status in cows with various abomasal disorders. J Vet Med Sci 57: , Tithof PK, Rebhun WC. Complications of blind-stitch abomasopexy: 20 cases ( ). J Am Vet Med. Assoc 189: , Trent AM. Surgery of the bovine abomasums. Vet Clin North Am Food Anim Pract 6: , Tulleners EP. Prevention and treatment of complications of bovine gastrointestinal surgery. Vet Clin North Am Food Anim Pract 6: , Turner AS, Mcllwraith CWo Bovine gastro-intestinal surgery. In: Techniques in large animal surgery. 2nd ed. Williams & Wilkins Co, Philadelphia, , Wallace CEo Left abomasal displacement-a retrospective study of 315 cases. Bovine Pract 10: 50-58, Whitlock RH. Diseases of the abomasum associated with current feeding practices. J Am Vet Med. Assoc. 154: , 1969.

10 Displacement of Abomasum and Its Performance on Clinical Serum Biochemistry in Dairy Cows in Taiwan 184 台灣乳牛第四胃異位及其臨床血清生化學之表現 聲莊士德 陳鵬文劉邦成張力天曾秋隆茅繼良馮翰鵬 國立中興大學獸醫學系台中市 { 收稿日期 : 89 年 10 月 5 日 接受日期 :90 年 4 月 17 日 ) t 面要第四胃異位可以說是台灣目前最常見的代謝性疾病之一, 本研究目的即在了解罹患此病牛隻的血清 各項離子的濃度變化以及評估手俯後的恢復情形 在本試驗中, 共有 50 個病例 ( % ) 被診斷出有第四 胃左側異位, 7 個病例有右側異位 (12.3%) 病牛的平均年齡為 3.83±1.14 歲以及平均有過 2.12±0.96 次 的分媲紀錄 % (16/57) 的病牛屬於第一次分婉的母牛, 40.4% (23/57) 病牛有兩次分挽紀錄, 26.3% (15/57) 病牛屬於有三次分挽記錄 ; 總共有 49 頭病牛 (86%) 在分繞後第一個月內發生第四胃異 位 ; 超過一半以上的病例 ( % 或 32/57 ) 發生在夏季月份 ( 六 七及八月 ) 0 57 頭第四胃異位的乳牛當 中, 有 45 頭 ( 78. 9% ) 併發關病, 且第四胃異位牛隻血清中的 Ca2\ Mg 2 + f 及 CI 等離子平均濃度均比同 牧場中正常牛雙的平均濃度低, 在統計學上並具有顯著性差異 ( P < ) 其他如 p2- 和 Na+ 的平均濃度則並 無顯著性差異 ( P > ) 根據本研究的結果, 我們認為右脅腹蜜的大網膜固定衛對於治療第四胃異位來 說, 是一個很好的外科方法, 而乳牛泌乳初期的低血鈣症則會增加此病的發生 [. 莊士德, 陳鵬文, 劉邦 成, 張力天, 曾秋隆, 茅繼良, 馮翰鵬 台灣乳牛第四胃異位及其臨床血清生化學之表現 中華民國獸醫誌 27 (3): 聯絡人 TE L : FAX: , stchuang@dragon.nchu.edu. tw] /Iliffj:!ffl!!l 厚, 黑五 t, JI1J.~ 津三芷 f 古箏,!/IA=