Dairy cow disability weights.

Over the past 175 years, data related to human disease and death have progressed to a summary measure of population health, the Disability-Adjusted Life Year (DALY). As dairies have intensified there has been no equivalent measure of the impact of disease on the productive life and well-being of animals. The development of a disease-adjusted metric requires a consistent set of disability weights that reflect the relative severity of important diseases. The objective of this study was to use an international survey of dairy authorities to derive disability weights for primary disease categories recorded on dairies. National and international dairy health and management authorities were contacted through professional organizations, dairy industry publications and conferences, and industry contacts. Estimates of minimum, most likely, and maximum disability weights were derived for 12 common dairy cow diseases. Survey participants were asked to estimate the impact of each disease on overall health and milk production. Diseases were classified from 1 (minimal adverse effects) to 10 (death). The data was modelled using BetaPERT distributions to demonstrate the variation in these dynamic disease processes, and to identify the most likely aggregated disability weights for each disease classification. A single disability weight was assigned to each disease using the average of the combined medians for the minimum, most likely, and maximum severity scores. A total of 96 respondents provided estimates of disability weights. The final disability weight values resulted in the following order from least to most severe: retained placenta, diarrhea, ketosis, metritis, mastitis, milk fever, lame (hoof only), calving trauma, left displaced abomasum, pneumonia, musculoskeletal injury (leg, hip, back), and right displaced abomasum. The peaks of the probability density functions indicated that for certain disease states such as retained placenta there was a relatively narrow range of expected impact whereas other diseases elicited a wider breadth of impact. This was particularly apparent with respect to calving trauma, lameness and musculoskeletal injury, all of which could be redefined using gradients of severity or accounting for sequelae. These disability weight distributions serve as an initial step in the development of the disease-adjusted lactation (DALact) metric. They will be used to assess the time lost due to dynamic phases of dairy cow diseases and injuries. Prioritizing health interventions based on time expands the discussion of animal health to view profits and losses in light of the quality and length of life.

Timpanismo ruminal crônico secundário à hipoplasia de pregas de omaso em dois bovinos / Chronic ruminal bloat secondary to omasal laminae hypoplasia in two cattle

Um novilho normando e outro charolês apresentando distensão abdominal, diarreia intermitente e timpanismo ruminal crônico, que iniciaram após desmame, foram enviados para necropsia. Observou-se ausência de pregas omasais associada à hipoplasia do órgão, assim como redução de tamanho das papilas ruminais e reticulares. Com base nas lesões e histórico, conclui-se que o timpanismo ruminal foi ocasionado pela falha no desenvolvimento do omaso...

Two emaciated juvenile steers, one Normande and one Charolaise breed with abdominal distension, intermittent diarrhea and chronic ruminal bloat that had begun at weaning were necropsied. Absence of the omasal laminae with omasal hypoplasia were found together with loss of ruminal papillae and reticular folds. Based on the lesions and history we concluded that the ruminal bloat was due to a development failure of the omasum...

Genome-wide association analysis identifies loci for left-sided displacement of the abomasum in German Holstein cattle.

Left-sided displacement of the abomasum (LDA) is one of the most common disorders of the digestive system in many dairy breeds and particularly in Holstein dairy cows. We performed a genome-wide association study for 854 German Holstein cows, including 225 cases and 629 controls. All cows were genotyped using the Illumina Bovine SNP50 BeadChip (Illumina Inc., San Diego, CA). After quality control of genotypes, a total of 36,226 informative single nucleotide polymorphisms (SNP) were left for analysis. We used a mixed linear model approach for a genome-wide association study of LDA. In total, 36 SNP located on 17 bovine (Bos taurus) chromosomes (BTA) showed associations with LDA at nominal -log10P-values >3.0. Two of these SNP, located on BTA11 at 46.70 Mb and BTA20 at 16.67 Mb, showed genome-wide significant associations with LDA at -log10P-values >4.6. Pathway analyses indicated genes involved in calcium metabolism and insulin-dependent diabetes mellitus to be factors in the pathogenesis of LDA in German Holstein cows.

Relationship between body condition score and health traits in first-lactation Canadian Holsteins.

The objective of this research was to estimate daily genetic correlations between longitudinal body condition score (BCS) and health traits by using a random regression animal model in first-lactation Holsteins. The use of indicator traits may increase the rate of genetic progress for functional traits relative to direct selection for functional traits. Indicator traits of interest are those that are easier to record, can be measured early in life, and are strongly genetically correlated with the functional trait of interest. Several BCS records were available per cow, and only 1 record per health trait (1=affected; 0=not affected) was permitted per cow over the lactation. Two bivariate analyses were performed, the first between BCS and mastitis and the second between BCS and metabolic disease (displaced abomasum, milk fever, and ketosis). For the first analysis, 217 complete herds were analyzed, which included 28,394 BCS records for 10,715 cows and 6,816 mastitis records for 6,816 cows. For the second analysis, 350 complete herds were analyzed, which included 42,167 BCS records for 16,534 cows and 13,455 metabolic disease records for 13,455 cows. Estimation of variance components by a Bayesian approach via Gibbs sampling was performed using 400,000 samples after a burn-in of 150,000 samples. The average daily heritability (posterior standard deviation) of BCS was 0.260 (0.026) and the heritabilities of mastitis and metabolic disease were 0.020 (0.007) and 0.041 (0.012), respectively. Heritability estimates were similar to literature values. The average daily genetic correlation between BCS and mastitis was -0.730 (0.110). Cows with a low BCS during the lactation are more susceptible to mastitis, and mastitic cows are likely to have low BCS. Daily estimates of genetic correlations between BCS and mastitis were moderate to strong throughout the lactation, becoming stronger as the lactation progressed. The average daily genetic correlation between BCS and metabolic disease was -0.438 (0.125), and was consistent throughout the lactation. A lower BCS during the lactation is genetically associated with the occurrence of mastitis and metabolic disease.

[Comparison of two methods of local anaesthesia for laparotomy in cattle]. / Vergleich zweier Lokalanästhesietechniken für die Laparotomie beim Rind.

OBJECTIVES: To compare the feasibility and efficacy of two methods of local anaesthesia with procaine 2% for flank laparotomy in cattle. MATERIAL UND METHODS: A total of 100 cattle undergoing laparotomy were divided into two groups of 50: one group underwent a modified infiltration anaesthesia (MIA) technique consisting of an incisional line block combined with an inverted L-block, and the other group underwent proximal paravertebral anaesthesia (PPVA). Indications for laparotomy were displaced abomasum, caecal disorders, rumenotomy and exploratory laparotomy. The two methods were compared with regard to the reaction of the cows to the application of anaesthesia, the degree of difficulty and the amount of time and anaesthetic agent required. The reactions of the cattle to incision of the various layers of the abdominal wall, abdominal exploration and surgical closure of the abdomen were assessed. RESULTS: Both techniques required a mean of 8 minutes to complete but the MIA method was considered more difficult than the PPVA (p=0.13). The PPVA required significantly (p<0.001) less procaine than the MIA (144 vs. 195ml). Comparison of the two techniques with respect to different types of pain reactions (no reaction, non-specific reaction, specific reaction) during cutting of the different layers of the abdominal wall revealed that PPVA provided significantly (p=0.01) better analgesia than the MIA. After PPVA, pain reactions to incision of the external oblique abdominal muscle were more severe, but reactions to abdominal exploration and to suturing the two oblique abdominal muscles were significantly (p<0.05) milder than after MIA. CONCLUSION AND CLINICAL RELEVANCE: Neither technique resulted in consistent and complete elimination of pain reactions in every patient, but overall PPVA had better results than the MIA. The analgesic effect of both techniques could be improved by repeated administration of procaine and mild tranquillization (Xylazine; 0.01mg/kg i.v.) before laparotomy. For PPVA, a combination of procaine and epinephrine should be used. It would be advantageous to have anaesthetic agents, e.g. lidocaine, that are more potent than procaine 2% for local analgesia in cattle.

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 Δ(9)-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 Δ(9)-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 Δ(9)-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.

Transcription factor binding site polymorphism in the motilin gene associated with left-sided displacement of the abomasum in German Holstein cattle.

Left-sided displacement of the abomasum (LDA) is a common disease in many dairy cattle breeds. A genome-wide screen for QTL for LDA in German Holstein (GH) cows indicated motilin (MLN) as a candidate gene on bovine chromosome 23. Genomic DNA sequence analysis of MLN revealed a total of 32 polymorphisms. All informative polymorphisms used for association analyses in a random sample of 1,136 GH cows confirmed MLN as a candidate for LDA. A single nucleotide polymorphism (FN298674:g.90T>C) located within the first non-coding exon of bovine MLN affects a NKX2-5 transcription factor binding site and showed significant associations (OR(allele) = 0.64; -log(10)P(allele) = 6.8, -log(10)P(genotype) = 7.0) with LDA. An expression study gave evidence of a significantly decreased MLN expression in cows carrying the mutant allele (C). In individuals heterozygous or homozygous for the mutation, MLN expression was decreased by 89% relative to the wildtype. FN298674:g.90T>C may therefore play a role in bovine LDA via the motility of the abomasum. This MLN SNP appears useful to reduce the incidence of LDA in German Holstein cattle and provides a first step towards a deeper understanding of the genetics of LDA.

Genetic parameters for producer-recorded health data in Canadian Holstein cattle.

Health traits are of paramount importance for economic dairy production. Improvement in liability to diseases has been made with better management practices, but genetic aspects of health traits have received less attention. Dairy producers in Canada have been recording eight health traits (mastitis (MAST), lameness (LAME), cystic ovarian disease (COD), left displaced abomasum (LDA), ketosis (KET), metritis (MET), milk fever (MF) and retained placenta (RP)) since April 2007. Genetic analyses of these traits were carried out in this study for the Holstein breed. Edits on herd distributions of recorded diseases were applied to the data to ensure a sufficient quality of recording. Traits were analysed either individually (MAST, LAME, COD) or were grouped according to biological similarities (LDA and KET, and MET, MF and RP) and analysed with multiple-trait models. Data included 46 104 cases of any of the above diseases. Incidence ranged from 2.3% for MF to 9.7% for MAST. MET and KET also had an incidence below 4.0%. Variance components were estimated using four different sire threshold models. The differences between models resulted from the inclusion of days at risk (DAR) and a cow effect, in addition to herd, parity and sire effects. Models were compared using mean squared error statistic. Mean squared error favoured, in general, the sire and cow within sire model with regression on DAR included. Heritabilities on the liability scale were between 0.02 (MET) and 0.21 (LDA). There was a moderate, positive genetic correlation between LDA and KET (0.58), and between MET and RP (0.79).

Metabolic predictors of post-partum disease and culling risk in dairy cattle.

A retrospective study was conducted to determine the relationship between serum non-esterified fatty acids (NEFA), ß-hydroxybutyrate (BHBA), glucose and calcium (Ca) with the occurrence of displaced abomasum (DA), clinical ketosis and culling in Holstein cows. Eight hundred and forty-nine cows from 16 farms were sampled weekly for the first 3 weeks post-partum. The cows were under clinical observation from calving until 60 days in milk (DIM) and during this time there were 22 cases of DA, 31 cases of clinical ketosis and 39 cows were culled. Elevated concentrations of BHBA were associated with DA, clinical ketosis and culling. In the first week after calving, cows with serum BHBA ≥1000µmol/L had 13.6 times greater odds of developing DA than cows with lower values. Serum NEFA and BHBA concentrations during week 1 were associated with the subsequent occurrence of clinical ketosis. The odds of clinical ketosis were 6.3 times greater in cows with serum NEFA ≥ 1.0mmol/L in the first week after calving. In addition, cows with BHB ≥1200µmol/L in the first week after calving, were at 4.7 times greater risk of developing clinical ketosis. In the first and second weeks after calving the serum Ca concentration was associated with subsequent culling. In addition, cows with NEFA concentration ≥ 1.0mmol/L were 3.6 times more likely to be culled within the following 2 months. The study indicated that early post-partum serum BHBA, NEFA and Ca concentrations have potential as indicators of disease and culling risk in dairy cows.

Mapping quantitative trait Loci for left-sided displacement of the abomasum in German Holstein dairy cows.

A whole-genome scan using an affected paternal half-sib design was utilized to detect quantitative trait loci (QTL) for left-sided displaced abomasum (LDA) in German Holsteins. A total of 360 animals from 14 paternal half-sib families were genotyped, for a total of 306 polymorphic microsatellites. For a whole-genome scan, 221 markers were equally distributed over all 29 bovine autosomes, with an average distance of 13.7 cM. For fine-mapping, a total of 85 additional microsatellites were used. We identified genome-wide significant QTL on Bos taurus autosome (BTA) 1 (54.6 to 58.3 cM) and on BTA3 (5.9 cM). Furthermore, 3 chromosome-wide significant QTL were located on bovine chromosomes 21, 23, and 24. In addition, we found 11 QTL that cosegregated in grandsire families but that were not significant in the across-family analysis. These QTL were located on BTA5, 6, 10, 12, 15, 16, 17, 19, 23, and 26. This study is the first report on QTL for LDA and is a first step toward identifying single nucleotide polymorphisms for LDA-QTL.

Leptin genotype is associated with lactation performance and health of Holstein cows.

The objectives were to evaluate the associations among single nucleotide polymorphisms (SNP) in the R4C locus in exon 2 of the leptin gene and the lactational performance and health of Holstein cows. Eight hundred and fourteen lactating dairy cows had their DNA sequenced in exon 2 of the leptin gene to determine the presence of SNP in the R4C locus. Cows were milked 3 times daily, and yields of milk and milk components were recorded monthly individually during the first 305 d of lactation. Cows were examined daily by herd personnel for diagnosis of health events such as retained fetal membranes, displacement of abomasum, lameness, and mastitis. Resulting genotypes were CC (34.6%), CT (48.2%), and TT (17.2%). Cows bearing the CT genotype had lower body condition (2.98 +/- 0.02) during the first 62 d in milk (DIM) than cows homozygous for the C (3.02 +/- 0.02) and T (3.04 +/- 0.03) alleles. Leptin genotype was associated with yields of milk and milk components, and cows homozygous for the C allele were less productive than those carrying the CT and TT genotypes. The 305-d yields of 3.5% fat-corrected milk, milk fat, and milk true protein were less in CC compared with CT cows by 258, 12, and 10.7 kg, respectively. Cows carrying the TT genotype had increased incidence of displacement of abomasum (4.3%), but genotype did not affect the incidence of retained fetal membranes, clinical and subclinical mastitis, or lameness. Risk of developing at least one clinical health disorder was influenced by leptin genotype, and cows carrying the CT genotype had the lowest risk for developing any disease (19.6%). Mating decisions to increase the frequency of cows heterozygous in the R4C locus may improve productivity and health.

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.

Minimally invasive field abomasopexy techniques for correction and fixation of left displacement of the abomasum in dairy cows.

To reduce the potential drawbacks associated with laparotomy techniques for correction and fixation of left displaced abomasums (LDA), minimally invasive techniques have been developed. This chapter reviews the toggle pin suture (TPS) and the laparoscopic abomasopexy procedures used in the field for correction and fixation of the abomasum for correction of left-displacement of the abomasum in dairy cows. The importance of case selection cannot be overestimated. By combining laparoscopy with the principle of the TPS procedure, the lack of visual control associated with the TPS procedure is eliminated, while the advantage of the speed of completion and minimal invasiveness provided by both procedures are maintained. Successful LDA treatment includes not only early detection and treatment of the LDA, but also the prevention of secondary ketosis and aggressive treatment of concurrent disease.

Surgery of the abomasum.

Abomasal diseases are common in cattle. Many of these diseases can be managed surgically. This article briefly discusses the various classifications of abomasal diseases. It focuses on the surgical treatment of these diseases. Surgical principles of conventional surgery and minimally invasive techniques are discussed.

An outbreak of sand impaction in postpartum dairy cows.

Twenty-two cases of indigestion occurred in a 650-cow herd. Five cows had severe sand abomasal impaction, diagnosed by laparotomy. The pH of prepartum cows' urine was < 6.0 and of sand 8.0. Feed showed a dietary cation-anion difference < or = -110 mEq/kg. After feeding management corrections, no more cases were diagnosed.

The use biochemical and hepatic parameters to predict treatment outcome of dairy cows suffering from displacement of the abomasum.

In this prospective study the impact of fatty liver and an impaired liver function on the treatment outcome of displacement of the abomasum (DA) was investigated. In a yearlong period, all cows suffering from DA submitted to the clinic were included in this study. All cows were clinically examined before surgery and a serum sample was taken to measure the following parameters: ASAT, bilirubin, urea. Liver biopsy was performed in all cows. Liver fat content was measured gravimetrically and concentrations of triglycerides were measured using a commercial test kit. Reposition of DA was done using the method by Dirksen. A total of 365 cows with DA entered the study, 326 (89.3%) suffered from LDA and 39 (10.7%) from RDA. RDA-cows had significantly (p = 0.002) more days in milk than LDA-cows. RDA-cows had significantly (p < 0.001) higher urea concentrations than LDA-cows. Bilirubin concentrations (p = 0.008) and liver fat content, triglyceride concentrations and the ratio of triglycerides to fat (TRI/FAT) (p < 0.001) were significantly higher in LDA-cows. The majority of LDA-cows showed at least a mild fatty liver. Comparing the cows with successful and failed treatment showed that ASAT-activity (p = 0.021), bilirubin concentration (p = 0.001), triglyceride concentration in liver and TRI/FAT (all p < 0.001) were significantly higher in the unsuccessfully treated cows. In RDA cows, significant differences between successfully and unsuccessfully treated cows were only seen in urea concentration (p = 0.004). ROC-analysis was performed to determine whether any parameter is suitable for a prediction of treatment outcome. In RDA-cows no threshold value was traceable for urea concentration. In LDA cows, TRI/FAT showed the best curve progression. The threshold value of 53.5 % had a sensitivity of 0.720 and a specificity of 0.700. LDA-cows exceeding this threshold had a 2.4 higher risk of an unsuccessful treatment. Due to the good overall treatment success (92.3 %) the positive predictive value for an unsuccessful or ineffective treatment was 0.368 only. The results of our study clearly show that impaired liver function plays an important role in the outcome of treatment of LDA but not RDA. In spite of this no laboratory parameter provides sufficient power to make a predictive statement of treatment outcome.

Evaluation of ornithine carbamoyl transferase and other serum and liver-derived analytes in diagnosis of fatty liver and postsurgical outcome of left-displaced abomasum in dairy cows.

OBJECTIVE: To evaluate postsurgical outcome in dairy cows with left-displaced abomasum (LDA) with regard to severity of fatty liver and assess the usefulness of preoperative determination of serum ornithine carbamoyl transferase (OCT) activity, bile acids concentration, and other variables for evaluating liver function during the postsurgical convalescence period. DESIGN: Prospective study. ANIMALS: 68 Holstein cows. PROCEDURES: Blood and liver biopsy specimens were obtained during standing LDA surgery. Liver tissue was examined histologically and classified by severity of fatty change. Serum activities of liver-derived enzymes and concentrations of total lipids, triglycerides, bile acids, glucose, beta-hydroxybutyric acid, bilirubin, and nonesterified fatty acids were determined. RESULTS: Most cows with LDA and cows with severe fatty liver were detected within the first month after calving. Postsurgical outcome was related to severity of fatty liver. All cows that died had severe fatty liver. Serum activities of OCT, aspartate aminotransferase, and glutamate dehydrogenase and serum total bilirubin concentration were sensitive indicators of fatty liver. Serum bile acids concentration was not an accurate indicator of fatty liver. CONCLUSIONS AND CLINICAL RELEVANCE: Postsurgical outcome of cows undergoing surgery to correct LDA was related to fatty liver severity. Assessment of serum activities of OCT, aspartate aminotransferase, and glutamate dehydrogenase and serum total bilirubin concentration is recommended for diagnosis of fatty liver in dairy cows with LDA, whereas determination of bile acids concentration is not. The strong correlation between OCT activity and degree of hepatocellular damage supports use of this enzyme for assessing severity of fatty liver and predicting postsurgical outcome in cows with LDA.

A new method for detecting the abomasal position and characteristics of movement at the onset of the left displacement of the abomasum in cows.

A new method has been developed by us to observe the movements of the abomasum by using a magnet and digital magnetometer. Four cows with left displacement of the abomasum underwent conventional correction by rolling without tacking. A doughnut-type magnet was sutured to the pyloric region in a routine operation. The same was done in three control cows. The position of the pyloric region was observed with a digital magnetometer from outside the cow's body. The magnets in the pyloric region of the control cows were located at the right side of the abdominal cavity at 10-30 cm anterior to the udder base, and moved slightly in various directions within the span of a day. On the other hand, the magnets in the pyloric region of cows with abomasal displacement moved widely in the abdominal cavity from the normal right side to the abnormal left front side. A large movement of the magnet from the normal right side to the abnormal left side of the abdominal cavity was observed within 12 h of the onset of abomasal displacement.

Comparison of the odds of isolation, genotypes, and in vivo production of major toxins by Clostridium perfringens obtained from the gastrointestinal tract of dairy cows with hemorrhagic bowel syndrome or left-displaced abomasum.

OBJECTIVE: To compare the frequency of isolation, genotypes, and in vivo production of major lethal toxins of Clostridium perfringens in adult dairy cows affected with hemorrhagic bowel syndrome (HBS) versus left-displaced abomasum (LDA). DESIGN: Case-control study. ANIMALS: 10 adult dairy cattle with HBS (cases) and 10 adult dairy cattle with LDA matched with cases by herd of origin (controls). PROCEDURE: Samples of gastrointestinal contents were obtained from multiple sites during surgery or necropsy examination. Each sample underwent testing for anaerobic bacteria by use of 3 culture methods. The genotype of isolates of C. perfringens was determined via multiplex polymerase chain reaction assay. Major lethal toxins were detected by use of an ELISA. Data were analyzed with multivariable logistic regression and chi2 analysis. RESULTS: C. perfringens type A and type A with the beta2 gene (A + beta2) were the only genotypes isolated. Isolation of C. perfringens type A and type A + beta2 was 6.56 and 3.3 times as likely, respectively, to occur in samples from cattle with HBS than in cattle with LDA. Alpha toxin was detected in 7 of 36 samples from cases and in 0 of 32 samples from controls. Beta2 toxin was detected in 9 of 36 samples from cases and 0 of 36 samples from controls. CONCLUSIONS AND CLINICAL RELEVANCE: C. perfringens type A and type A + beta2 can be isolated from the gastrointestinal tract with significantly greater odds in cattle with HBS than in herdmates with LDA. Alpha and beta2 toxins were detected in samples from cows with HBS but not from cows with LDA.