Left Displacement Of The Abomasum Research Articles

Investigation of gastrointestinal injury-related biomarkers in dairy cattle with displaced abomasum.

Displaced abomasum (DA) is one of the most important metabolic disorders of dairy cattle. In DA, ischaemic damage may occur as a result of impaired perfusion due to abomasal displacement, which may result in gastrointestinal mucosal damage. Investigation of gastrointestinal tissue damage in cattle with right displacement of the abomasum (RDA) and left displacement of the abomasum (LDA) using intestinal-related biomarkers. Forty-eight DA (24 LDA, 24 RDA) and 15 healthy Holstein dairy cows were enrolled between March 2021 and July 2022. Serum biomarkers including gamma-enteric smooth muscle actin (ACTG-2), liver-fatty acid binding proteins (L-FABP), platelet activating factor (PAF), trefoil factor-3 (TFF-3), leptin, claudin-3 and interleukin-8 (IL-8) concentrations were measured from venous blood samples. L-FABP concentrations in the LDA group and TFF-3 concentrations in the RDA group were lower than in the control group. The leptin concentration of the RDA group was higher than that of the other groups. There was a negative correlation between lactate, leptin and IL-8 concentrations. There was a negative correlation between lactate and TFF-3, whereas leptin and lactate were positively correlated. Leptin was the more reliable biomarker for discriminating between RDA and LDA cases. Changes in serum L-FABP, TFF-3 and leptin concentrations in cattle with DA may reflect acute intestinal injury and the subsequent repair phase. However, these biomarkers had poor diagnostic performance in discriminating between healthy and cattle with DA, while leptin emerged as the most useful marker in differentiating LDA from RDA cases.

One-Step Laparoscopic Abomasopexy for Left Displacements of the Abomasum in Pregnant Cattle: A Retrospective Study

Although technical descriptions have been published, the applicability of left-flank laparoscopy for the surgical correction of left displacement of the abomasum (LDA) in pregnant cattle has not yet been fully assessed. This study aimed to investigate the postoperative performance of one-step laparoscopic abomasopexy for the correction of LDA during late pregnancy. Fifteen pregnant Holstein cattle with LDA were treated with one-step laparoscopic abomasopexy between days 259 and 274 of gestation. This technique was performed in a standing position. Under endoscopic observation via trocars introduced from the left flank, the animals underwent a surgical procedure to place the bar part of a toggle-pin-suture (TPS) device into the lumen of the abomasum through a long cannula. A suture of a TPS device was secured to the ventral abdominal wall by using a long applicator. No cases experienced postoperative complications, and all had a normal delivery on postoperative day 17.4 ± 4.9. Three of the 15 animals exhibited foot diseases and mastitis after calving. The reproductive performance was recorded during lactation periods, showing a service conception rate of 2.9 ± 1.2 and 110.5 ± 39.1 open days. The one-year survival rate was 60% (9/15). The positive postoperative results demonstrate the benefits of one-step laparoscopic abomasopexy in pregnant bovine cases with LDA.

Retrospective Evaluation of Method of Treatment, Laboratory Findings, and Concurrent Diseases in Dairy Cattle Diagnosed with Left Displacement of the Abomasum during Time of Hospitalization.

Simple SummaryLeft displacement of the abomasum (LDA) is a common disease in high-producing dairy cattle, resulting in direct and indirect costs, discomfort for the cattle, and death if not treated. The objectives of this retrospective study were to assess the effect of treatment on recovery from LDA during time of hospitalization, to investigate the influence of concurrent diseases on the recovery, and to identify prognostic indicators in laboratory findings. Neither the number of concurrent diseases nor the method of surgery had any influence on the outcome (death or recovery). The most common concurrent disease was metritis/endometritis (38.4% of cows). Conservative treatment (abomasal rolling) was successful in 92.8% of cows, with a recurrence rate of 56.7%. Neither oral nor analgesic therapy had any influence on the recurrence of LDA following abomasal rolling during hospitalization. In cows undergoing surgery, endoscopic abomasopexy as described by Janowitz and right flank laparotomy were performed most often (40.8% and 40.2%, respectively). A significantly (p < 0.01) higher number of cows showed the outcome “recovery” compared with “death”. The results of this study indicate that the outcome after surgery for LDA under clinical conditions does not depend on the method of surgery, and that concurrent diseases are often diagnosed in cattle with LDA. Conservative treatment has a high recurrence rate.Left displacement of the abomasum (LDA) is a disease often diagnosed in high-producing dairy cattle, resulting in direct and in indirect costs for the farmer, and discomfort and death for the cows. For the present retrospective study, the aims were to assess the effect of treatment on recovery during the time of hospitalization of the cows, to investigate the influence of concurrent diseases on the recovery, and to identify prognostic indicators in laboratory findings. Metritis/endometritis (38.4% of cows) was the concurrent disease diagnosed most often. Conservative treatment (abomasal rolling) was performed successfully in 92.8% of cows; the recurrence rate was 56.7%. Neither treatment with an oral drench nor treatment with analgesics had any influence on the recurrence of LDA following abomasal rolling during hospitalization. Endoscopic abomasopexy as described by Janowitz was performed more often than right flank laparotomy (40.8% and 40.2%, respectively). A significantly (p < 0.01) higher number of cows had the outcome “recovery” compared with “death”. The results of this study show that the outcome after surgery for LDA under clinical conditions does not depend on the method of surgery. Moreover, cows with LDA often suffer from concurrent diseases. If conservative treatment is decided on, farmers should be informed that there is a high recurrence rate, and other treatment options should be discussed.

Left displacement of the abomasum in a reticulated giraffe bull in managed care.

A 10-y-old giraffe (Giraffa camelopardalis reticulata) bull developed colic after a 3-mo history of reduced feed consumption. Physical examination and management were performed with 2 standing sedations. The giraffe developed metabolic alkalosis and progressive pre-renal azotemia followed by compensatory respiratory acidosis and paradoxical aciduria. A metallic "ping" sound was auscultated on the left side near ribs 10-12. The giraffe was euthanized given the grave prognosis, and postmortem examination confirmed left displacement of the abomasum (LDA) with fluid sequestration (150-190 L [40-50 gal]) within the rumen. Dental disease was evident at postmortem examination and perimortem skull computed tomography. To ensure cases of LDA are not overlooked, the position of the abomasum must be noted during postmortem examination prior to removal of the gastrointestinal tract. The risk factors for the development of LDA in giraffes are not known, and associations such as those of dairy cattle (hypocalcemia, high-concentrate low-fiber diet, and indoor housing) remain to be elucidated.

Postoperative wound assessment in cattle: How reliable is the back hand palpation?

BackgroundAs part of clinical wound assessment in bovine surgery, discrepancies in skin temperature are evaluated by placing the back of the hand on the area to be examined. Generally, an increased skin temperature at the wound site for a prolonged period is considered as an indicator of impaired wound healing.The aim of this study was to verify the reliability of palpation under bovine practice conditions using laparotomy as an example. Fourteen cows (German Holstein) with a left displacement of the abomasum (LDA) without other severe concurrent diseases were examined preoperatively and once daily for ten days after surgery. The skin temperature of the wound site in the right flank was assessed by palpation, followed by thermographic evaluation using an infrared camera after a 45-min acclimatisation period, under standardised conditions in a closed examination room daily for 10 days.ResultsAll the incisions healed without clinical detectable perturbances. The ambient temperature range during the study period was 7.8 − 24.1 °C. Two groups were retrospectively defined according to the ambient temperature: high ambient temperature (HT group; median: 20.2 °C 25/75 quartile: 18.5 °C / 21.7 °C; n = 6) and low ambient temperature (LT group; 10.8 °C; 9.4 °C / 12.8 °C; n = 8). The temperature differences (Δϑ) between the mean skin temperature of the wound site and a defined reference area cranial to the wound were assessed. A significant negative correlation was found between the ambient temperature (ϑAmb) and Δϑ (r=-0.51; P < 0.001). The Δϑ was postoperatively higher in the cows in the LT group (median of the individual animals 0.8–2.5 °C) than in the HT group (0.1–0.5 °C; P < 0.05). In contrast to the thermographic findings, manual palpation rarely detected local hyperthermia (> 1 °C) at the wound site (sensitivity 0.20; specificity 0.96).ConclusionsThe infrared thermography provides a more reliable assessment of temperature changes at the wound site in comparison to manual palpation. The ambient temperature markedly affects the extent of local hyperthermia at the wound site.

Retrospective Evaluation of Claw Lesions, Inflammatory Markers, and Outcome after Abomasal Rolling in Cattle with Left Displacement of the Abomasum

Simple SummaryLameness is a major welfare problem in cattle and is often diagnosed concurrent to left displacement of the abomasum. Lame cattle prefer to lie on the affected leg, and laterality of lying may have an effect on the etiology of left displacement of the abomasum. The objective of this study was to investigate the possible association between laterality of claw lesion and presence of left displacement of the abomasum. For this study, the data of 252 cattle were analyzed retrospectively. Inclusion criteria were: a diagnosis of left displacement of the abomasum and diagnostic examination of claw lesions during hospitalization at the clinic. There was no association between laterality of claw lesion and left displacement of the abomasum. Cattle with a claw lesion in their right limbs were not diagnosed with left displacement of the abomasum more often than cattle with claw lesions in their left limbs. A total of 46.4% of cattle were diagnosed with at least one claw lesion. These results emphasize the importance of the prevention of claw lesions, especially in the post-partum period, to improve cattle welfare.Lameness is often diagnosed in cattle with left displacement of the abomasum (LDA). Laterality of lying has an effect on the etiology of LDA, and lame cows prefer to lie on the affected limb. The objective of this study was to investigate the possible association between laterality of claw lesion and presence of LDA. The medical records of 252 cattle presented with a diagnosis of LDA and subjected to a diagnostic examination of claw lesions over a period of 11 years (2009–2019), were analyzed retrospectively. Data were evaluated for presence and localization of claw lesion, concentrations of inflammatory markers, and abomasal rolling as therapy. At least one claw lesion was diagnosed in 46.4% of cattle. There was no association between laterality of claw lesion and LDA. Presence of claw lesion or oral drench and/or analgesic treatment did not have an effect on occurrence of relapse. A high number of cattle was diagnosed with both LDA and claw lesions. Focus should lie on preventing painful claw lesions in the dry and the early post-partum period. The high recurrence rate after abomasal rolling suggests that abomasal rolling should only be considered as a therapy for temporary relief, and surgical procedures should be discussed with farmers.

Ultrasonographic documentation of type-3 abomasal ulcer in a cow with left displacement of the abomasum

BackgroundUltrasonographic documentation of perforated abomasal ulcer has not been published till now. This report describes the clinical, ultrasonographic and postmortem findings in a Jersey cow with type-3 abomasal ulcer and left displacement of the abomasum (LDA).Case reportThe main clinical findings were abnormal demeanour, rumen atony and tympany, positive foreign body tests, positive auscultation and simultaneous ballottement on the left side, abdominal guarding and loss of negative pressure in the abdominal cavity. The tentative diagnosis was peritonitis and LDA. Abdominal ultrasonography produced images typical of LDA, and in one location between the abdominal wall and abomasum there was a layer of fibrin, a fibrin clot, a break in the abomasal contour, suggestive of a perforated ulcer, and partial obstruction of this gap with fibrin. The diagnosis of perforated abomasal ulcer with subsequent peritonitis was confirmed during postmortem examination.ConclusionsThe examination of this case shows that under certain circumstances, ultrasonographic imaging of a perforated abomasal ulcer in a cow is possible. Antemortem diagnosis of type-3 abomasal ulcer is preferable to relying on exploratory laparotomy and/or post-mortem examination.

Identification of disordered metabolic networks in postpartum dairy cows with left displacement of the abomasum through integrated metabolomics and pathway analyses.

High-producing dairy cows are easily affected by left displacement of the abomasum (LDA) within 4 weeks postpartum. Although LDA is highly associated with metabolic disturbances, the related information on comprehensive metabolic changes, with the exception of some blood biochemical parameters, remains limited. In this study, the changes in plasma metabolites and in the metabolic profile of postpartum dairy cows with LDA were investigated through liquid chromatography coupled with quadrupole time of flight mass spectrometry (LC-Q/TOF-MS)-based metabolomics, and the metabolic networks related to LDA were constructed through metabolomics pathway analysis (MetPA). An obvious change in the metabolic profile was reflected by significant variations in 68 plasma metabolites in postpartum dairy cows with LDA, and these variations consequently altered 13 metabolic pathways (histidine metabolism, tyrosine metabolism, valine, leucine and isoleucine biosynthesis, phenylalanine, tyrosine and tryptophan biosynthesis, arginine and proline metabolism, tryptophan metabolism, synthesis and degradation of ketone bodies, linoleic acid metabolism, arachidonic acid metabolism, citrate cycle, butanoate metabolism, vitamin B6 metabolism and pyrimidine metabolism). This study shows that the more detailed information obtained by LC-Q/TOF-MS-based metabolomics and MetPA might contribute to a better understanding of the disordered metabolic networks in postpartum dairy cows with LDA.

Evaluation of Oxidative Stress in Dairy Cows with Left Displacement of Abomasum.

Simple SummaryThe present study evaluated oxidative and antioxidant status in dairy cows with Left Displacement of the Abomasum (LDA), an economically important postpartum disease in cattle. The oxidant capacity of plasma measured with a test fo reactive oxygen metabolites, the d-ROMs test, was significantly higher and the plasma biological antioxidant potential (BAP), measured with the BAP test was lower in the LDA group compared with the control group. Oxidative status was assessed using an arbitrary index obtained from the ratio between d-ROMs and BAP and the results showed that cows with LDA experience an imbalance between oxidants and antioxidants.Left Displacement of the Abomasum (LDA) is a condition that occurs in high-producing postpartum dairy cows and it causes economic losses. Studies performed in the last decade indicate that adult dairy cows experience oxidative stress. Increasing interest in the role of oxidative status in ruminant medicine has emphasized the need to develop reliable methods to assess it. A few studies have evaluated the relationship between LDA and oxidative status, mostly through the determination of single parameters of oxidation and the determination of antioxidant status separately, with contrasting results. The aim of this study was to assess the oxidative status by the measurement of Reactive Oxygen Metabolites with d-ROMs and Biological Antioxidant Potential BAP and the calculation of the Oxidative Status index in 74 multiparous dairy cows with LDA. Each case was matched with a control herdmate. The amount of free oxygen radicals in plasma samples was determined using the d-ROMs test, the concentration of antioxidants was measured using the BAP test and the Oxidative Status index was also calculated. The concentration of d-ROMs was significantly higher in the study group compared to the control group (179 ± 37.7 U CARR and 158 ± 23.0 U CARR, respectively), while the concentration of BAP was significantly lower in the study group than in the control group (2156 ± 98.1 µmol/L vs. 2558 ± 108.5 µmol/L). The Oxidative Status index value was significantly higher in cows with LDA than in healthy cows (8.3 ± 1.51 vs. 6.2 ± 0.76). The results of this study indicated that an inbalance between oxidants and antioxidants occurred in cattle with LDA.

Alterations of pancreatic functions and lipid profiles in dairy cows with left displacement of the abomasum

The objectives of this study were to determine the serum activities of the pancreatic enzymes amylase, lipase, trypsinogen 1 and trypsinogen 2, serum concentrations of total cholesterol, high density lipoprotein, low-density lipoprotein and triglycerides and serum inflammatory indicators, namely C-reactive protein and procalcitonin, in Holstein-Friesian dairy cows with left displacement of the abomasum (LDA). A total of 60 cows (30 LDA-affected and 30 healthy) were included in the study. Laboratory analyses were performed using commercially available ELISA kits and chemical reagents according to the manufacturers’ recommendations. There was a significant increase (P ≤ 0.05) in the activities of lipase, trypsinogen 1 and trypsinogen 2 in LDA-affected cows compared to healthy cows. Amylase concentrations, however, remained unchanged. The serum concentrations of total cholesterol and high-density lipoprotein were significantly (P ≤ 0.05) increased in LDA-affected cows while the concentrations of low-density lipoprotein and triglycerides were significantly (P ≤ 0.05) decreased compared to healthy cows. Procalcitonin and C-reactive protein concentrations were significantly (P ≤ 0.05) increased in LDA-affected cows compared to healthy cows. This study indicates that displacement of the abomasum may be associated with significant pathological effects in the pancreas that may affect cows in the post-operative period.

Association between left-displaced abomasum corrected with 2-step laparoscopic abomasopexy and milk production in a commercial dairy farm in Italy

BackgroundLeft displacement of the abomasum (LDA) is a condition of dairy cows that causes huge economic losses. The aim of the study was to evaluate the effect of LDA after on-farm correction by the 2-step laparoscopic abomasopexy on milk production based on 305-d milk yield on a commercial dairy farm in Italy.The study was performed between January 2011 and January 2014 on 58 Holstein Friesian cattle with left displacement of the abomasum in a commercial dairy farm in the farmland of Ozieri, Sardinia (Italy). Each cow underwent a 2-step laparoscopic abomasopexy performed by the same veterinarian. Each case was matched with a control herdmate by age, parity and calving date. Cows with LDA and healthy control cows also had a similar 305-d milk yield in the previous lactation. Data on milk production were collected using a dairy herd management software programme (Afimilk®, Afimilk Ltd., Israel). The 305-d lactation yield was obtained from the sum of daily milk yields for each cow. An unpaired Student’s t-test was used to compare changes in milk production, mean fat and protein percentage of cases and controls before and after surgical procedure.ResultsData from 4 cows were excluded from the analysis due to post-surgical complications. 54 cases and 54 control cows participated in the study. We found that milk production significantly decreased from a baseline of 12,295 ± 1690 kg to 11,165 ± 1989 kg in the affected lactation. Conversely, a significant increase was observed for mean fat and protein percentage during lactation in case cows.ConclusionsIn the present study cows with left displacement of the abomasum corrected with 2-step laparoscopic abomasopexy produced less milk than their control herdmates. Each case and control pair in the present study came from the same farm in order to eliminate farm to farm differences in management, housing, season, etc. However, this limits the validity of our data to the specific situation described here.

Application of a laparoscopic spieker of own design in reposition and fixation of the left displacement of the abomasum (LDA) in cattle.

The first case of the left displacement of the abomasum was described in 1950 by Begg. Since then, the LDA has been diagnosed worldwide. It has been shown that there is a correlation between its increased occurrence and an increase in the intensity of cattle dairy production. The treatment methods include surgical ones, which are aimed at two objectives: reposition and fixation of the abomasum to the abdominal wall. The methods using the classic laparotomy include median abomasopexy, right-sided omentopexy and left-sided abomasopexy. A second group of surgical methods consists of procedures that are minimally invasive. These include percutaneous fixation, which requires positioning the patient on the back, and laparoscopic procedures performed by Janowicz and modified by Christiansen and later on by Newman. Recently, laparoscopic methods have become increasingly accessible and popular. The aim of the study was to evaluate the efficacy of laparoscopic treatment of the LDA, using equipment of the authors’ own design. The study involved the observation of 10 cows (aged between 24 and 90 months) treated surgically not later than 24 hours after the diagnosis. These animals were operated on with modified instruments. The modification presented here consisted in making a tube equipped with a trocar lock, which made it possible to reposition the abomasum non-traumatically and to fix it at the bottom of the abdomen. Signs of normal behaviour were observed, and all animals were eating and ruminating within 3-6 hours after surgery. The modification of the spieker proposed by the authors shortens laparoscopy and makes it safer by eliminating iatrogenic complications, such as accidental perforation of the bowels or diaphragm by the trocar edge..

Changes of hematological and biochemical parameters and levels of pepsinogen, histamine and prostaglandins in dairy cows affected with left displacement of the abomasum.

The aims of this study were to determine the serum levels of pepsinogen, histamine, and prostaglandins F2α and E2 in lactating dairy cows affected with left displacement of the abomasum (LDA). In addition, the hematological and serum biochemical parameters were also determined in cows affected with LDA. A total of 52 adult lactating Holstein-Friesian cows affected with LDA and 30 normal cows (control) were used. In LDA cows, the average age, BCS and body weight were 4.9 ± 1.2 years, 2.5 ± 0.75, and 525 ± 150kg respectively. The average days-in-milk (DIM) in affected cows was 14 ± 6 with a range between 7 to 45 days. There were no significant differences in values of rectal temperature, heart rate and respiration rate between LDA cows and control. Rumen motility was significantly (p≤0.05) decreased in LDA cows. Cows affected with LDA had significantly (p≤0.05) increased glucose levels, and decreased levels of calcium and magnesium. There were significantly (p≤0.05) increased serum levels of pepsinogen and histamine in LDA cows while levels of prostaglandin E2 were significantly decreased in comparison to those in control cows. There were no significant changes in serum levels of prostaglandin F2α. In the hematology analyses, there were no significant changes in cows with LDA when compared to those in control cows. This study provides evidence of a possible role for pepsinogen, histamine and prostaglandin E2 in the etiopathophysiology of LDA in dairy cows.

Assessment of the excretion time of electronic capsules placed in the intestinal lumen of cows with cecal dilatation-dislocation, healthy control cows, and cows with left displacement of the abomasum.

To analyze the transit time from various locations in the intestines of cows with cecal dilatation-dislocation (CDD), healthy control cows, and cows with left displacement of the abomasum (LDA). 15 cows with naturally occurring CDD (group 1), 14 healthy control cows (group 2), and 18 cows with LDA (group 3). 5 electronic transmitters were encased in capsules and placed in the lumen of the ileum, cecum, proximal portion of the colon, and 2 locations in the spiral colon (colon 1 and colon 2) and used to measure the transit time (ie, time between placement in the lumen and excretion of the capsules from the rectum). Excretion time of the capsules from each intestinal segment was compared among groups. Cows recovered well from surgery, except for 1 cow with relapse of CDD 4 days after surgery and 2 cows with incisional infection. High variability in capsule excretion times was observed for all examined intestinal segments in all groups. Significant differences were detected for the excretion time from the colon (greater in cows with CDD than in healthy control cows) and cecum (less in cows with LDA than in cows of the other 2 groups). The technique developed to measure excretion time of capsules from bovine intestines was safe and reliable; however, the large variability observed for all intestinal segments and all groups would appear to be a limitation for its use in assessment of intestinal transit time of cattle in future studies.

Adding evidence for a role of the SLITRK gene family in the pathogenesis of left displacement of the abomasum in Holstein-Friesian dairy cows

Left displacement of the abomasum (LDA) is a frequent disease in Holstein-Friesian cattle with a big economic impact in dairy farms. LDA is a multi-factorial disease and genetics is known to play a role (low to moderate estimated heritability). It is therefore of interest to look for genetic polymorphisms associated with LDA in order to find involved genes and clarify the pathogenesis of the condition. In a population of 62 Italian Holstein-Friesian cows, LDA cases and SNP genotypes were recorded, and a genome-wide association study (GWAS) was performed. A genetic signal of association with LDA was detected on BTA 12, within the sequence of the SLITRK5 gene. This gene is involved in neurological activities such as axonogenesis and synaptic transmission, and this may be related with abomasal hypomotility and atony, which are considered the primary causes of LDA. The results of this research suggest a role for the SLITRK5 gene, and more generally for all nearby genes of the SLITRK family, in the pathogenesis of LDA in dairy cattle. The involvement of the SLITRK gene family may lead to novel approaches for the prevention, diagnosis and therapy of LDA, and could also be used in enhanced selection schemes for healthier animals.

Relationships between metabolite and IGF1 concentrations with fertility and production outcomes following left abomasal displacement

Left displacement of the abomasum (LDA) is an important periparturient disorder of dairy cows. This study evaluated differences in metabolic parameters between case-control pairs of cows (n=67) from 24 farms,...

Peritoneal inflammatory response to surgical correction of left displaced abomasum using different techniques

The objective of this study was to compare the inflammatory response within the abdominal cavity between three surgical methods. The study comprised 45 cows with left displacement of the abomasum,...

Effects of β-hydroxybutyrate and different calcium and potassium concentrations on the membrane potential and motility of abomasal smooth muscle cells in cattle

The left displacement of the abomasum (LDA) is a common disease in periparturient dairy cows. Plasma β-hydroxybutyrate (BHBA) levels above the reference range are regarded as risk factors for the occurrence of LDA. Additionally, hypokalemia and hypocalcemia have been observed in LDA cows. The aim of the present study was to characterize the membrane potential and the slow waves in abomasal smooth muscle cells by a microelectrode technique and to determine possible effects of BHBA and of various calcium and potassium concentrations on the membrane potential. Subsequently, the results obtained by the microelectrode technique were combined with in vitro motility experiments of abomasal smooth muscles. Strips of the abomasal circular smooth muscles were prepared and incubated in different buffer solutions. For the microelectrode technique, healthy bulls and cows that underwent surgery for LDA were sampled. These measurements showed a frequency of the slow waves between 3.5 and 10.9 per minute (for amplitudes ≥3mV) and between 0.6 and 4.5 per minute (for amplitudes ≥5mV). The frequency of contractions (1.8 to 3.1 per minute) were in the same order as the frequency of the slow waves with amplitudes ≥5mV. Blocking potassium conductance with barium chloride induced a depolarization of the basal membrane potential (from −43±2.9 to −37±4.1mV; mean ± standard error of the mean) without affecting the frequency or the height of the slow waves. The reduction in the potassium concentration from 5.4 to 2mmol/L resulted in a nominal decrease in the activity of contractions (from 22.2 to 18.6mN/min). The subsequent addition of 1mmol of KCl/L induced a nominal increase in contraction activity (from 18.6 to 25.7mN/min). An effect of BHBA (5mmol/L) could not be demonstrated, neither on the electric nor on the motility parameters. A simulated hypocalcemia (1.2mmol/L total, 0.9mmol/L ionized Ca) did not change slow waves and motility. In conclusion, changes in membrane potential ≥5mV correlated with contractions of abomasal muscles. Hypokalemic conditions may reduce abomasal contraction activity via an effect on the membrane potential. An exclusive increase in BHBA or a slight hypocalcemia (0.9mmol/L ionized Ca) had no effects on the motility of healthy abomasal smooth muscle cells. A prolonged or severe exposition of muscles to a combination of low Ca and high BHBA concentrations might nevertheless be able to affect abomasal motility.

The fatty acid profile of subcutaneous and abdominal fat in dairy cows with left displacement of the abomasum

The objective of this study was to determine the fatty acid (FA) profile and assess desaturase indices of nonesterified fatty acids (NEFA) in the blood, as well as in the abdominal (ABD) and subcutaneous (SUBC) fat stores, in dairy cows with left displacement of the abomasum (LDA). Blood, ABD, and SUBC samples were taken from 50 Holstein cows offered for surgery to correct LDA. The FA profile of the 3 compartments was determined by gas chromatography after lipid extraction, methylation, and, in the case of blood plasma, separation of lipid classes. The most abundant FA in all 3 compartments were 16:0, 18:0, and 18:1 cis-9, with a total proportion of 82.5, 68.0, and 74.1g/100 g of FA in ABD, NEFA, and SUBC, respectively. A principal component analysis was performed on the entire FA profile as well as on the Δ9-desaturase indices (14:1 cis-9/14:0, 16:1 cis-9/16:0, 18:1 cis-9/18:0). The principal component analysis extracted 2 principal components (PC), representing 51.6% (PC1) and 21.1% (PC2) of the total variance in FA composition of the 3 compartments. The loading plot for the regression factors revealed a strong positive correlation between PC1 with the Δ9-desaturase indices and the proportions of 14:1 cis-9 and 16:1 cis-9, and revealed a negative correlation with the proportion of 18:0 and saturated FA. The correlation with PC2 was positive for the proportion of unsaturated FA, 18:2n-6, and 18:3n-3, and negative for the proportion of 14:0, 16:0, and saturated FA. The SUBC could be distinguished from the NEFA and ABD by a positive score for PC1, whereas differentiation among the latter 2 compartments could be made by a positive (NEFA) or negative (ABD) score for PC2. The Δ9-desaturase indices for C14 and C16 differed between all compartments but were numerically closer for NEFA and ABD versus NEFA and SUBC. The desaturase indices of the main FA (18:1 cis-9 and 18:0) did not differ between NEFA and ABD. These results support the existence of a different FA composition in ABD compared with SUBC. The greater similarity between the FA profiles of ABD and NEFA compared with SUBC and NEFA and the closer desaturase indices of ABD and NEFA support the hypothesis of a preferential mobilization of ABD fat in dairy cows with LDA.

Displaced abomasum in cattle: evaluation beyond the ping

SURGERY of the abomasum appears to be the most common abdominal surgery in dairy practice. Left displacement of the abomasum (LDA) occurs more frequently than abomasal volvulus (AV), but AV...