Origin of abomasum gas in the cows with displaced abomasum

The gas composition of the rumen and the abomasum were investigated in 71 cows including 25 cows with displaced abomasum. The ratio of methane (CH4) to CO2 in the abomasum gas was higher than that in the rumen. In the incubated mixtures of fresh rumen fluid, CH4 was detected at a high concentration, while a small amount of CO2 and CH4 was found in incubated mixtures of fresh abomasum fluids. Hence, it was suggested that the gas in the abomasum originated not from the abomasum itself but from the rumen. In cows fed with mixed roughages and concentrates, the rumen CO2:CH4 ratio was higher compared with cows fed with roughages alone. Marked changes in rumen gas composition were presumed to be associated with changes in abomasum gas composition. Consequently, it is possible that feeding a large quantity of concentrates may increase the flow rate of the ingesta through the forestomach, so that the return rate of gas separated from the ingesta in the abomasum to the forestomach may also increase. Therefore, the frequent accumulation of a large amount of gas with concomitant changes in the total volatile fatty acid (VFA) concentration in the abomasum caused abomasal atony and subsequently displaced abomasum.     

Changes in peripheral leukocyte subsets in dairy cows with inflammatory diseases after calving

To clarify the cellular immune system in dairy cows with inflammatory diseases after calving, the leukocyte subsets were examined in Holstein dairy cows. Twenty Holstein cows reared in one herd, were used in this study. Nine cows (Group 1) experienced onset of mastitis or puerperal fever within 2 weeks after calving, and the other eleven cows remained healthy (Group 2) after calving. The numbers of CD3(+), CD4(+) and CD8(+) cells tended to be lower in Group 1 than in Group 2 from the day of calving through week 1. These results suggested that the cows with inflammatory diseases might have experienced a decline in T cells by the day of calving, before the onset of disease.     

Polymorphonuclear leukocyte function in cattle with left displaced abomasum with or without concurrent infections

Cattle submitted to the University of Minnesota for surgical correction of left displaced abomasum (LDA) were examined for the in vitro phagocytic and bactericidal activities of their polymorphonuclear leukocytes (PMN). The PMN from cattle with LDA with or without concurrent infection had depressed phagocytic function when compared with PMN from healthy animals (controls). Those with concurrent infection had phagocytic activities lower than those in the group of cattle with LDA without any concurrent infection, and the former group was also observed to have depressed intracellular killing. Cattle with LDA complicated by infection were the only group in which phagocytic function was altered during surgical correction of LDA (and recovery). Treatment of PMN from both groups of affected cattle with levamisole in vitro enhanced intracellular killing, but had no effect on phagocytosis.     

Prevalence of endotoxemia in healthy postparturient dairy cows and cows with abomasal volvulus or left displaced abomasum

Left displaced abomasum (LDA) and abomasal volvulus (AV) occur most commonly in postparturient dairy cows. Our main hypothesis was that endotoxemia occurred more frequently in the peripheral blood of cows with LDA or AV than in healthy cows because increased luminal pressure in AV or LDA, or the presence of a hemorrhagic strangulating obstruction in AV, may have injured the abomasal mucosa, thereby facilitating translocation of luminal endotoxin into the circulation. Therefore, our main objective was to compare the prevalence and magnitude of endotoxemia in healthy postparturient cows with the prevalence and magnitude of endotoxemia in cows with AV and LDA. We examined 60 adult dairy cows in early lactation that were diagnosed with AV (n = 15) or LDA (n = 15) or were healthy on physical examination (control group, n = 30). Jugular venous blood was obtained from cows in all 3 groups, and right gastroepiploic venous blood was obtained during surgical correction of AV and LDA immediately after repositioning of the abomasum. Platelet-rich plasma endotoxin concentrations were measured with a chromogenic limulus amoebocyte lysate assay. Endotoxin was detected in jugular vein plasma in 50% (15/30) of control cows; however, the prevalence of endotoxemia was significantly lower (P < .05) in cows with AV (7%, 1/15) or LDA (20%, 3/15). Endotoxin was detected simultaneously in right gastroepiploic and jugular vein plasma in only 1 cow with LDA and 0 cows with AV. Contrary to our hypothesis, we conclude that endotoxemia is infrequently present in postparturient dairy cows with AV or LDA.     

Relationships between lactational incidence of displaced abomasum and milk production traits in German Holstein cows

The objective of this study was to analyse the heritabilitiy of the lactational incidence of displaced abomasum (DA) and the relationships of DA with milk production traits in German Holstein cows. Data were recorded between February 1999 and January 2000 in cooperation with five veterinary practitioners. Their veterinary practices were located in the northern part of Lower Saxony. The investigation included 160 dairy farms under the official milk-recording scheme with 9,315 cows. The lactational incidence of the left abomasal displacement amounted to 1.21%, and of the right abomasal displacement to 0.41%, respectively. The linear heritability estimates for the lactational incidences of left and right DA were h(2) = 0.05 +/- 0.012 and h(2) = 0.004 +/- 0.005, respectively. Using the Dempster-Lerner-transformation the corresponding heritabilities were h(2) = 0.53 and 0.09, respectively. Milk losses for the lactation when DA was diagnosed were significant and reached 1016 kg milk, 41 kg fat, 36 kg protein and 0.07% protein. Fat content significantly increased by 0.18%. The analysis could not show significant differences between cows diagnosed with DA and cows not diagnosed with DA in the 305-day milk production traits of the lactation preceding the diagnosis of DA. There was also no indication for an unequal distribution of breeding values for milk performance traits between cows with and without DA. The additive genetic correlations between 305-day milk performance and left DA were low. The results indicated that cows with a high milk production and superior breeding values for milk performance were not exposed to an increased risk for DA.     

Position of the abomasum in dairy cows during the first six weeks after calving

The position of the abomasum in six cows was examined by ultrasonography at regular intervals for six weeks after they had calved. Its position was established by determining the distance between the margin of the left side of the abomasum and the ventral midline at two sites. During the last weeks of pregnancy, the abomasum was positioned in a small region of the left ventral side of the abdominal cavity. At parturition it was positioned high on the left side and then descended. The abomasum was furthest from the midline immediately after parturition. Its position was related to the interval after calving, the cow's feed intake, and the pH and osmotic pressure of the rumen fluid. There was considerable variation between the cows in the position of the abomasum, which was in part due to analytical variation, and in individual cows it had a circadian rhythm.     

Factors influencing the survival of dairy cows after correction of left displaced abomasum

OBJECTIVE: To determine factors that influenced culling or death of cows with left displaced abomasum (LDA) subsequent to correction by a roll-and-toggle (R&T) procedure or via laparotomy. DESIGN: Cohort study. ANIMALS: 810 Holstein dairy cows with LDA. PROCEDURES: Data regarding method of repair and risk factors for survival after correction of LDA were collected during a 1-year period. Outcomes were compared at days 14 and 60 after LDA correction for 3 groups of cattle (veterinarians performed R&T [V-R&T], herd personnel performed R&T [H-R&T], and veterinarians performed surgical repair via laparotomy [V-Surg]). RESULTS: Survival rates 14 days after LDA correction for the V-R&T, H-R&T, and V-Surg groups were 87% (286/329), 81% (327/403), and 85% (66/78), respectively. At 60 days after LDA correction, survival rates for the V-R&T, H-R&T, and V-Surg groups were 79% (260/329), 71% (286/403), and 73% (57/78), respectively. Multivariable analysis indicated that factors positively associated with failure to remain in the herd at 60 days after LDA correction included current mastitis status, history of a previous LDA, high preoperative risk, and correction of LDA by herd personnel rather than by a veterinarian. CONCLUSIONS AND CLINICAL RELEVANCE: Correction of LDA by veterinarians via an R&T procedure yielded results that were generally comparable to those for correction by veterinarians via laparotomy. Although survival rates at days 14 and 60 after surgery differed significantly between the V-R&T and H-R&T groups, herd personnel in this study used the R&T procedure to correct LDA and achieved survival rates within the range for those of practicing veterinarians.     

Changes in mRNA of immune factors expressed by milk somatic cells of Holstein cows with hypocalcemia after calving

Changes in immune factors expressed by milk somatic cells from Holstein cows with hypocalcemia after calving were investigated in this study. Fourteen multiparous Holstein cows after their 3rd or 4th calving in one farm were used. The cows were divided into 2 groups: 7 cows needing treatment due to onset of hypocalcemia (hypocalcemia group; age = 5.53 ± 0.27 years, parity = 3.14 ± 0.14) and 7 cows without health problems (control group; age = 5.88 ± 0.31 years, parity = 3.57 ± 0.26). Milk samples were collected aseptically using a cannula and mRNA of immune factors expressed by milk somatic cells were analyzed. Milk samples (50 mL) were collected from the right rear mammary gland of cows before milking at day 1 and weeks 1, 2, 4, and 8 after calving. All milk samples showed a negative reaction to the California Mastitis Test. Levels of relative interleukin (IL)-6 and cathelicidin in the hypocalcemia group were lower than those in the control group in weeks 1 to 8. A significant difference in relative IL-6 levels was found in week 4 (P < 0.05). These results suggest that levels of IL-6 expressed by milk somatic cells may be affected by hypocalcemia in dairy cows.     

Comparison of abomasal luminal gas pressure and volume and perfusion of the abomasum in dairy cows with left displaced abomasum or abomasal volvulus

OBJECTIVE: To compare abomasal luminal gas pressure and volume and perfusion of the abomasum in dairy cows with a left displaced abomasum (LDA) or abomasal volvulus (AV). ANIMALS: 40 lactating dairy cows (25 with an LDA and 15 with an AV). PROCEDURE: Abomasal luminal gas pressure and volume and pulse oximetry values for the caudal portion of the dorsal ruminal sac and abomasal wall were measured during laparotomy. Abomasal perfusion was assessed on the basis of abomasal O2 saturation (pulse oximetry) before correction of the LDA or AV. Abomasal perfusion was also assessed after correction of the LDA or AV by measuring venous O2 saturation in the right gastroepiploic vein and calculating the abomasal oxygen-extraction ratio. RESULTS: Abomasal luminal gas pressure and volume were higher in cattle with an AV than in cattle with an LDA. Abomasal O2 saturation was lower and abomasal oxygen-extraction ratio higher in cattle with an AV, compared with values in cattle with an LDA. In cows with an AV, lactate concentration in the gastroepiploic vein was greater than that in a jugular vein, whereas no difference in lactate concentrations was detected in cows with an LDA. Abomasal luminal gas pressure was positively correlated (r, 0.51) with plasma lactate concentration in the gastroepiploic vein and negatively correlated (r, -0.32) with abomasal O2 saturation determined by use of pulse oximetry. CONCLUSIONS AND CLINICAL RELEVANCE: Abomasal perfusion decreases as luminal pressure increases in cattle with an AV or LDA.     

Peritoneal fluid analysis in dairy cows with left displaced abomasum and abomasal volvulus

Peritoneal fluid (PF) was evaluated in 40 cows with left displaced abomasum (LDA) and 15 cows with abomasal volvulus (AV). PF was obtained by abdominocentesis at the right ventral abdomen at admission. Simultaneously, a blood sample was taken from the jugular vein. Biochemical and cytological variables in blood and PF specific for ischaemia, inflammation and cell damage were compared. Total protein, albumin, glucose and cholesterol were normal in PF of cows with LDA and AV. Although L-lactate increased in both groups, cows with AV had significantly higher values (LDA: 1.47/0.69/2.68 mmol/l; AV: 6.45/4.55/12.89 mmol/l (median/1. quartile/3. quartile)). D-dimer (LDA: 0.50/0.22/0.88 mg/l; AV: 1.11/0.40/1.85 mg/l) and LDH (LDA: 663/437/943 U/l; AV: 1099/750/1439 U/l) were only increased in PF of cows with AV. The number of leucocytes was normal; however, significantly more peritoneal neutrophils appeared necrotic or apoptotic after AV. PF of cows with abomasal displacement showed distinctive features of ischaemia and inflammation. Characteristics of haemostatic dysfunction and cell damage were mainly evident in PF of cows with AV. The results suggest that anti-inflammatory therapy is indicated in each cow with abomasal displacement. Additionally, medical treatment should be directed to prevent complications of ischaemia and reperfusion in cows with AV.     

Changes in peripheral blood mononuclear cells after calving in lactating cows with serious decrease of body weight before and after calving

The aim of this study was to clarify the hormonal and immunological changes in periparturient dairy cows with excessive weight loss following calving. We analyzed leukocyte populations and the peripheral blood mononuclear cell (PBMC) mRNA of IFN-gamma, IL-4, growth hormone (GH)-receptor (R) and insulin -R and measured the GH and insulin concentrations. Ten dairy cows fed in one herd were used in this study and were divided into two groups. Five cows that experienced loss of body weight following calving of over 10% comprised the Weight Loss Group, and the remaining five cows, which experienced loss of body weight of 5% or less following calving, served as the Control Group. The Weight Loss Group had high serum cholesterol and low blood urea nitrogen levels compared with the Control Group throughout the period of observation. In regard to the leukocyte populations, there were significantly fewer CD4(+)CD45R-T cells in the Weight Loss Group 1 to 2 months after calving compared with the Control Group. The percentage of IFN-gamma/IL-4 among PBMCs in the Weight Loss Group tended to be lower than in the Control Group throughout the observation period. In the Weight Loss Group, the levels of GH-R during month 2 were lower than in the Control Group. We concluded that excessive loss of body weight in dairy cows following calving is associated with depressed cellular immune function.     

Changes in leukocyte population after ozonated autohemoadministration in cows with inflammatory diseases

In this study, we investigated whether ozonated autohemoadministration (OAHA) influences leukocyte populations in cows with clinical inflammatory disease. Eleven cows with inflammatory disease (Inflammatory Group) and three healthy cows (Control Group) were used for this study. The CD4(+)/CD8(+) ratio in the Inflammatory Group increased significantly compared to that in the Control Group 3 to 4 days after OAHA treatment. In the Inflammatory Group, the number of CD14(+) cells decreased gradually after OAHA, but CD14(+) levels remained stable in the Control Group. The number of MHC class-II(+) cells decreased gradually in the Inflammatory Group, but increased gradually in the Control Group, and the difference between the groups was significant on day 14 after OAHA. These findings suggest a possible difference in the activation of immune response after OAHA in infected cows compared to healthy cows.     

Use of the D-xylose absorption test to measure abomasal emptying rate in healthy lactating Holstein-Friesian cows and in cows with left displaced abomasum or abomasal volvulus

We determined the abomasal emptying rates of Holstein-Friesian cows at different stages of lactation, with left displaced abomasum (LDA), or immediately after surgical correction of LDA or abomasal volvulus (AV). D-xylose (0.5 g/kg body weight [BW], 50% solution) was injected into the abomasum in healthy cows (group 1, 4-7 days in milk [DIM], n = 7; group 2, 90-120 DIM, n = 7; group 3, > 300 DIM, n = 7) and in cows with LDA (n = 10; group 4). D-xylose was injected into the abomasum during right flank laparotomy in cows with LDA (n = 22; group 5) and cows with AV (n = 15; group 6). The time to maximal serum D-xylose concentration was used as an index of emptying rate. The abomasal emptying rates for cows in groups 1, 2, and 3 were similar, whereas emptying was slower in cows with LDA and in cows after surgical correction of LDA or AV. The abomasal emptying rate of cows with LDA was slowed to a greater extent immediately after surgery, when compared to the rate obtained before surgery. There was no difference in abomasal emptying rate immediately after surgical correction between cows with LDA or AV. The results indicate that the increased incidence of LDA in the first month of lactation is not associated with an intrinsic decrease in abomasal emptying rate in healthy cows. Our findings also demonstrate that surgical correction further slows the emptying rate in cows with LDA.     

The association of displaced abomasum with various periparturient factors in dairy cows. A retrospective study

The associations between displaced abomasum (DA) and various factors in seven dairy herds were investigated. The overall rate of DA in 7026 calving cows was 1.7%. All cows were routinely clinically examined between 5 and 14 days post partum. DA was found, by a retrospective analysis, to be associated in terms of increased relative risk, R, with rising parity, stillbirth (R = 1.97), twins (R = 3.25), retained placenta (R = 6.62), primary metritis (R = 4.26), aciduria (R = 6.17), ketonuria (R = 33.04), and a low milk yield before calving (R = 2.29). No association was established between DA and milk fever. The significance of the associations in relation to the aetiology of the disease, with special reference to the fat cow syndrome, is discussed, and the possible role played by the ruminal acidosis associated with the various factors is investigated.     

Abomasal luminal pressure in cattle with abomasal volvulus or left displaced abomasum.

The abomasal luminal pressure was determined during surgery in 54 dairy cows with abomasal volvulus (AV) and another 50 dairy cows with left displaced abomasum. The luminal pressure was high in all cattle with AV and 49 (98%) cattle with left displaced abomasum. Luminal pressure was significantly higher in cattle with AV (median, 11.7 mm of Hg; range, 4.1 to 32.4 mm of Hg) than cattle with left displaced abomasum (median, 8.7 mm of Hg; range, 3.5 to 20.7 mm of Hg). Among cattle with AV, abomasal luminal pressure was significantly higher in cattle that died or were sold for slaughter following surgery (median, 20.6 mm of Hg; n = 8) than in cattle that were retained in the herd (median, 11.0 mm of Hg; n = 46). The luminal pressure was weakly correlated with the preoperative serum alkaline phosphatase activity but not correlated with duration of inappetence before surgery. Calculation of likelihood ratios and construction of a response operating characteristic curve for cattle with AV indicated that a cut-off value of 16 mm of Hg for luminal pressure optimized the distribution of cattle into productive and nonproductive groups. The sensitivity, specificity, positive predictive value, and negative predictive value of a luminal pressure < 16 mm of Hg in predicting a productive outcome were 0.83, 0.75, 0.95, and 0.43, respectively.     

An evaluation of protein/fat ratio in first DHI test milk for prediction of subsequent displaced abomasum in dairy cows.

First DHI test milk that was sampled prior to displaced abomasum (DA) diagnosis was used to evaluate milk protein/fat ratio (PFR) for prediction of subsequent DA in dairy cows. Odds ratio, sensitivity, specificity, and likelihood ratio were determined. Twenty-seven DA cases were matched to 3 controls per case by herd and calving date. Milk was tested at a median of 19 d after calving, which was 8 d prior to the median time of DA diagnosis. Adjusted for parity and days in milk, a protein/fat ratio < or = 0.72 was 8.2 times more likely to come from a cow subsequently diagnosed with DA than a protein/fat ratio > 0.72. Using the cut off value of 0.72, the sensitivity of PFR for DA was 80% and the specificity was 68%. A receiver operating characteristics curve indicated that the minimum sum of false negative and false positive results was at a PFR cut off value of 0.72. The likelihood ratio indicated that protein/fat ratios < or = 0.62 are 3.8 times more likely to come from cows that are diagnosed subsequently with DA than from cows without DA. The protein/fat ratio in 1st DHI test milk may predict subsequent DA in dairy cows.     

Blood parameters in Swedish dairy herds with high or low incidence of displaced abomasum or ketosis

Sixty dairy herds were studied to investigate the association between long-term incidence of displaced abomasum and clinical ketosis and body condition score and blood profiles, including parameters estimating energy metabolism and hepatic lipidosis in the periparturient period and early lactation. Blood samples were taken around parturition and in early lactation from cows without apparent clinical symptoms of metabolic disorders. A difference in metabolism between high and low incidence herds was shown post-partum by a lower metabolic index (the revised Quantitative Insulin Sensitivity Check Index, RQUICKI), and tendencies for higher concentrations of glucose, insulin and non-esterified fatty acids in the high incidence herds. High incidence herds had more cows and produced on average 1400kg energy-corrected milk per cow per year more than the low incidence herds. No differences were found in parameters reflecting liver cell damage. In the first 3weeks post-partum the RQUICKI was a more sensitive marker of herds with a high incidence of displaced abomasum and clinical ketosis than any of the individual parameters, but further research is needed before practical applications of the RQUICKI can be foreseen.