Observations on ascites in nine cattle

Signs of ascites were observed in only nine of 1863 cattle examined over a period of five years. The ascites was most commonly associated with either primary or secondary cardiac disease; cattle with ascites have a poor prognosis because the condition is usually assocaited with terminal disease. Two animals had cor pulmonale with chronic pneumonia, three had cardiomyopathy, one had bacterial endocarditis, two had thrombosis of the caudal vena cava and one had diffuse abdominal epithelioid mesothelioma.     

Correlation between leukocytosis and necropsy findings in dogs with immune-mediated hemolytic anemia: 34 cases (1994-1999)

OBJECTIVE: To determine whether severity of leukocytosis correlates with severity of postmortem lesions in dogs with immune-mediated hemolytic anemia (IMHA). DESIGN: Retrospective study. ANIMALS: 34 dogs with IMHA that had CBC performed within 48 hours prior to death and complete necropsy examinations. PROCEDURE: Dogs were independently assigned to 4 leukocytosis groups (within reference range; mild leukocytosis, moderate leukocytosis, marked leukocytosis) and 3 lesion severity groups (mild lesions, moderate lesions, severe lesions). RESULTS: Moderate to marked leukocytosis correlated with moderate to severe postmortem lesions. Ischemic necrosis within liver, kidney, heart, lung, and spleen attributable to thromboembolic disease or anemic hypoxia were the most common important lesions found at necropsy. None of the dogs with mild lesions had moderate or marked leukocytosis. Four of 14 severely affected dogs had WBC counts within reference range, but all 4 had neutrophilic left shifts. Three of these 4 dogs had toxic change in neutrophils. CONCLUSION AND CLINICAL RELEVANCE: Moderate to marked leukocytosis, neutrophilic left shift, and toxic change in neutrophils in dogs with IMHA should alert clinicians to the potential for moderate to severe tissue injury, which could complicate treatment and worsen prognosis. Lesions appear to be secondary to anemic hypoxia, thromboembolic disease, or both; therefore, treatment objectives should focus on improving blood oxygen-carrying capacity and monitoring for thromboembolic disease.     

Spirometric performance in Belgian Blue calves: I. Effects on economic losses due to the bovine respiratory disease complex

The aim of this study was to determine whether high spirometric performances in calves are associated with low economic losses due to the bovine respiratory disease complex (BRDC). Five spirometric variables (SV) were measured in 909 double-muscled Belgian Blue calves from 15 to 60 d of age. Afterward, calves were monitored for 6 mo to determine whether they developed BRDC and to determine the costs due to BRDC (i.e., medicine costs and veterinarians' fees, plus estimated financial losses due to mortality in case of death). To analyze the effects of spirometric performances on BRDC cost, a fixed linear model was used for each SV. In addition to SV, each model included the effects of sex, dam's parity, vaccination status, muscular development score, herd-period, and BW. Only herd-period and the maximal ventilation and the vital capacity had significant effects on costs due to BRDC, indicating that these two SV are major physiological determinants of economic losses associated with BRDC. Accordingly, it is assumed that an amelioration of maximal ventilation and vital capacity could result in increased resistance to BRDC in calves.     

Passive immunization of pigs against experimental infection with Streptococcus suis serotype 2

The safety and protective efficacy of a horse antiserum raised against inactivated whole cell preparations of Streptococcus suis serotype 2 was investigated in pigs by experimental challenge. The antiserum was evaluated in two similar experiments each comprising 12 4-week-old pigs treated with 6 ml of antiserum the day before challenge and four pigs used as challenge controls. Pigs were infected by subcutaneous injection with approximately 10(11) colony forming units of S. suis serotype 2. Clinical disease in the pigs that could be attributed to infection with S. suis was reduced from 88 to 35% (P = 0.015). The percentage of pigs with lesions that could be associated with S. suis was reduced from 88 to 22% (P = 0.002) and isolation of S. suis serotype 2 was reduced from five (63%) out of eight pigs in the combined challenge control groups to 3 (13%) out of 23 pigs in the combined treatment groups. These results indicate that passive immunization of pigs may be a way to reduce or control S. suis serotype 2 infections in pigs.     

Effect of walking velocity on ground reaction force variables in the hind limb of clinically normal horses

OBJECTIVE: To measure the effect of subject velocity on hind limb ground reaction force variables at the walk and to use the data to predict the force variables at different walking velocities in horses. ANIMALS: 5 clinically normal horses. PROCEDURE: Kinematic and force data were collected simultaneously. Each horse was led over a force plate at a range of walking velocities. Stance duration and force data were recorded for the right hind limb. To avoid the effect of horse size on the outcome variables, the 8 force variables were standardized to body mass and height at the shoulders. Velocity was standardized to height at the shoulders and expressed as velocity in dimensionless units (VDU). Stance duration was also expressed in dimensionless units (SDU). Simple regression analysis was performed, using stance duration and force variables as dependent variables and VDU as the independent variable. RESULTS: Fifty-six trials were recorded with velocities ranging from 0.24 to 0.45 VDU (0.90 to 1.72 m/s). Simple regression models between measured variables and VDU were significant (R2 > 0.69) for SDU, first peak of vertical force, dip between the 2 vertical force peaks, vertical impulse, and timing of second peak of vertical force. CONCLUSION AND CLINICAL RELEVANCE: Subject velocity affects vertical force components only. In the future, differences between the forces measured in lame horses and the expected forces calculated for the same velocity will be studied to determine whether the equations can be used as diagnostic criteria.     

EXCRETORY UROGRAPHY BY INTRAOSSEOUS INJECTION OF CONTRAST MEDIA IN A RABBIT MODEL

There are many indications for an intravenous excretory urogram. However, where intravenous access is not available, the intraosseous route to the circulation may be an alternative. We found that safe and diagnostic excretory urograms could be obtained in rabbits following the injection of different contrast media via the intraosseous route. In fact, these excretory urograms were indistinguishable from ones obtained by the conventional intravenous route. While the rabbits did not develop any abnormal clinical signs following the procedure, there were postmortem histologic lesions of osteochondrosis in 5 of 22 (22.7%) tibias receiving an intraosseous needle, but in none of the 14 tibias that did not receive an intraosseous needle. Further, the use of diatrizoate was associated with the development of osteochondrosis while the use of iopamidol was not.     

Monthly model for genetic evaluation of laying hens 1. Fixed regression.

1. This paper addresses the possibility of using a monthly model for the genetic evaluation of laying hens, based on the definition of a test day model with fixed regression as used in dairy cattle, in which monthly records were treated as repeated measurements of the same trait. 2. Production records of 6450 hens, daughters of 180 sires and 1335 dams were analysed using an animal model with restricted maximum likelihood (REML). The traits considered were individual monthly egg production and cumulative egg production in 11 months. Four different models were fitted to various combinations of monthly and cumulative records. The covariates were derived from the regression of Ali and Schaeffer (1987). 3. Spearman rank correlations were computed to compare breeding values from different models. Two types of correlations were computed: between individual breeding values and between sire breeding values based on subsets of full-sib records. 4. The results indicated that a monthly model with nested covariates produced higher heritability and permanent environmental variance than the models with non-nested or without covariates. The estimates of heritability obtained from monthly model were lower than the estimates from the cumulative model. The monthly model resulted in higher correlations of sire breeding values between two subsets of full-sib records than those from cumulative models. 5. In conclusion, the monthly model with nested covariates appears to be better than the model with non-nested covariates or without covariate. Although the heritability estimates obtained from the monthly model were lower, the monthly model with nested covariates could be better than the cumulative model for genetic evaluation of laying hens in the 1st cycle of laying period when using either full or part records. The use of information from odd months of production could be of interest for the evaluation of full records.     

Molecular analysis of field strains of Mycoplasma capricolum subspecies capripneumoniae and Mycoplasma mycoides subspecies mycoides, small colony type isolated from goats in Tanzania.

A molecular analysis of strains of Mycoplasma capricolum subsp. capripneumoniae (M. capripneumoniae) and Mycoplasma mycoides subsp. mycoides, small colony type (M. mycoides SC) isolated from goats was performed using the amplified fragment length polymorphism (AFLP) and pulsed-field gel electrophoresis (PFGE) fingerprinting techniques. Among the 11 field strains of M. capripneumoniae from Tanzanian goats, two AFLP patterns were demonstrated, with 10 of the strains showing indistinguishable patterns. Five Kenyan strains of M. capripneumoniae produced three AFLP patterns, with two of them being indistinguishable from the 10 identical Tanzanian and one Ugandan strain (M74/93) isolated from sheep. The AFLP pattern of the type strain (F38(T)) was identical to two Kenyan strains (Baringo and G183/82). On PFGE analysis, all the examined M. capripneumoniae strains exhibited identical PFGE profiles.Five field strains of M. mycoides SC isolated from goats displayed identical AFLP patterns except for one strain which differed from others at only one position. The AFLP pattern of the type strain of M. mycoides SC (PG1(T)) was different from the field strains. The five field strains of M. mycoides SC produced identical PFGE profiles, which were, however, different from the type strain. The AFLP and PFGE profiles of M. mycoides SC strains from goats were identical to those of six strains isolated from cattle affected with contagious bovine pleuropneumonia (CBPP) in the same areas. The results of this study suggest a close epidemiological linkage between strains of M. capripneumoniae and between M. mycoides SC type, respectively, isolated from goats in Tanzania.     

Early weaning and postweaning nutritional management affect feedlot performance of angus x simmental heifers and the relationship of 12th rib fat and marbling score to feed efficiency

Early-weaned Angus x Simmental heifers were used to evaluate the effects of postweaning nutritional management on feedlot performance, carcass merit, and the relationship of intramuscular and subcutaneous fat deposition to the feed efficiency among heifers fed for a high-quality market. Sixteen heifers were weaned at 73+/-5.5 d of age and grazed on endophyte-infected tall fescue for 18 mo before entering the feedlot (early-weaned-P). Eighty heifers from the following year's calf crop were weaned at 71+/-5.5 d of age and allowed either ad libitum access to a 25% concentrate diet (early-weaned-25C) or limit-fed a 90% concentrate diet (early-weaned-90C) to achieve a similar ADG. Following a 119-d growing period, 16 early-weaned-90C and 16 early-weaned-25C calves were paired based on BW and growth rate and individually fed during the finishing period along with the early-weaned-P heifers. Ultrasound measurements of s.c. and i.m. fat were recorded at approximately 60-d intervals throughout the finishing period. Feed efficiency was regressed against s.c. and i.m. fat, and i.m. fat was regressed on s.c. fat. Despite a similar ADG, early-weaned-90C calves gained more efficiently (P < or = 0.05) in the feedlot than early-weaned-25C calves. Heifers finished as yearlings tended (P < or = 0.10) to gain faster but gained less efficiently (P < or = 0.01) than early-weaned-90C heifers finished as calves. The rate of s.c. and i.m. fat deposition was similar between early-weaned-90C and early-weaned-25C heifer calves. The calves were grouped together for comparison to yearlings. Feed efficiency decreased quadratically (P < or = 0.01) as s.c. fat cover increased. The rate at which feed efficiency decreased relative to increasing s.c. fat cover was similar regardless of age at feedlot entry. However, heifers finished as calves gained more efficiently (P < or = 0.01) than yearlings at any given fat thickness. Feed efficiency decreased linearly (P < or = 0.01) as i.m. fat increased among heifers finished as calves. Additionally, heifers finished as calves deposited i.m. fat at a faster rate relative to s.c. fat (P < or = 0.01) than yearlings. These data suggest that heifers finished as calves produce high-quality carcasses with less s.c. fat cover while gaining more efficiently than heifers finished as yearlings.