Effect of milk sampling techniques on milk composition, bacterial contamination, viability and functions of resident cells in milk.

Three different milk sampling techniques were evaluated during milk sampling: a direct aseptic collection from the udder through a sterile cannula was used as the reference technique, compared with either a manual or a mechanical sampling method. In this study 30 high-yielding Holstein-Friesian dairy cows at different stages of lactation and free of udder infection were used. For each milk sample, the influence of milk sampling techniques was determined for the following parameters: somatic cell count, milk composition, bacterial contamination, viability, in vitro phagocytosis and overall killing of Staphylococcus aureus Newbould 305, and cellular chemiluminescence. Because milk sampling occurred throughout lactation, the differences between early, mid- and late lactation were estimated. It was concluded that bacterial contamination was not significantly different in manual milking samples and the reference technique; bacterial contamination was, however, significantly (P < 0.001) higher in machine milking samples than in the reference technique. Among the different sampling techniques, no significant effects on SCC, milk composition, viability and functions of the cells isolated from milk were observed. It was found that viability, intracellular killing and cellular chemiluminescence of milk PMN were significantly lower (P < 0.05) in early lactation compared to mid-lactation. Phagocytosis was significantly (P < 0.05) higher in early lactation compared to mid- and late lactation, and no significant differences were observed between mid- and late lactation. From this study, it can be concluded that despite a higher bacterial contamination obtained with the mechanical sampling method, the 3 milk sampling techniques described in this study can be used for the evaluation of milk cell functions.     

RADIOGRAPHIC FINDINGS OF CANINE DYSAUTONOMIA IN TWENTY-FOUR DOGS

Canine dysautonomia is an idiopathic condition resulting in loss of autonomic nervous system function. Recently, the prevalence of dogs diagnosed with dysautonomia in the mid-western United States has increased. In this study the medical records and radiographic findings in 24 dogs with dysautonomia were reviewed. A diagnosis of dysautonomia was made in 17 (71%) of the dogs in this study by postmortem examination, the remaining 7 (29%) dogs were diagnosed pharmacologically. The radiographic findings supportive of dysautonomia include aspiration pneumonia, megaesophagus, or a distended stomach, small bowel, or urinary bladder. In some instances, the disease radiographically mimicked other disorders of the gastrointestinal tract, including mechanical obstruction.     

Use of an antineoepitope antibody for identification of type-II collagen degradation in equine articular cartilage.

OBJECTIVE: To develop an antibody that specifically recognizes collagenase-cleaved type-II collagen in equine articular cartilage. SAMPLE POPULATION: Cartilage specimens from horses euthanatized for problems unrelated to the musculoskeletal system. PROCEDURE: A peptide was synthesized representing the carboxy- (C-) terminus (neoepitope) of the equine type-II collagen fragment created by mammalian collagenases. This peptide was used to produce a polyclonal antibody, characterized by western analysis for reactivity to native and collagenase-cleaved equine collagens. The antibody was evaluated as an antineoepitope antibody by ELISA, using peptides +/- an amino acid at the C-terminus of the immunizing peptide. Collagen cleavage was assayed from equine articular cartilage cultured with interleukin-1 (IL-1), +/- a synthetic MMP inhibitor, BAY 12-9566. Cartilage specimens from osteoarthritic and nonarthritic joints were compared for antibody staining. RESULTS: An antibody, 234CEQ, recognized only collagenase-generated 3/4-length fragments of equine type-II collagen. This was a true antineoepitope antibody, as altering the C-terminus of the immunizing peptide significantly decreased competition for binding in an inhibition ELISA. The IL-1-induced release of type-II collagen fragments from articular cartilage was prevented with the MMP inhibitor. Cartilage from an osteoarthritic joint of a horse had increased staining with the 234CEQ antibody, compared with normal articular cartilage. CONCLUSIONS AND CLINICAL RELEVANCE: We generated an antineoepitope antibody recognizing collagenase-cleaved type-II collagen of horses. This antibody detects increases in type-II collagen cleavage in diseased equine articular cartilage. The 234CEQ antibody has the potential to aid in the early diagnosis of arthritis and to monitor treatment responses.     

Use of laser photocoagulation for treatment of cutaneous angiomatosis in one dog and two cats.

One dog and 2 cats were evaluated because of multiple progressively enlarging cutaneous vascular plaques. Biopsies were performed and revealed small well-circumscribed dermal nodules of dilated fully enclosed blood-filled spaces lined by single layers of endothelial cells aligned on thin fibrous walls, with minimal mitotic activity. A diagnosis of cutaneous angiomatosis was made in all 3 animals. Cutaneous angiomatosis is a progressive proliferative lesion of vascular tissue involving the dermis and subcutaneous tissues of dogs and cats. Lasers of selected wavelengths have been used to induce photothermal coagulation of hemoglobin-containing cutaneous lesions in humans; argon-pumped dye and neodymium:yttrium-aluminum-garnet lasers were used to treat the cutaneous lesions in the animals of this report. Laser treatment may provide an alternative to wide surgical resection or limb amputation for management of this condition in veterinary patients.     

Simple techniques for the internal stabilization of fractures and luxations in the sacrococcygeal region of cats and dogs.]

Two useful techniques for the repair of caudal sacral fractures and sacrococcygeal fractures/luxations are described. Pre- and postoperative clinical, neurological and radiological findings in 16 operated animals (13 cats and 3 dogs) were compared with findings in 17 (13 cats and 4 dogs) conservatively treated animals. In the surgically treated patients follow up findings were characterized by absence of hyperesthesia and a higher number of animals with recovered tail function. The authors suggest the use of these techniques in cases of caudal sacral fractures or sacrococcygeal fractures/luxations.     

Immunohistochemical Detection of Mycoplasma agalactiae in Formalin‐Fixed,Paraffin‐Embedded Tissues from Naturally and Experimentally Infected Goats

Samples from the mammary tissue of 14 lactating goats (12 naturally infected and two experimentally infected) were examined for the presence of Mycoplasma agalactiae. A monoclonal antibody (5G12) was applied to formalin‐fixed, paraffin‐wax‐embedded sections and labelled by the avidin–biotin peroxidase complex (ABC) method. Histological examination of tissue sections revealed strong immunoreactivity in all animals included in the study. Mycoplasma agalactiae antigen was mainly detected in the cellular debris at the periphery of purulent exudates present within lactiferous sinuses, and lactiferous and interlobular ducts. In addition, M. agalactiae organisms appeared in the cytoplasm of the epithelium of ducts, and in infiltrating macrophages and neutrophils within the ducts, alveoli, interstitial tissue and regional lymph node sinuses. It is concluded that this monoclonal antibody‐based immunohistochemical technique is an efficient and specific method for the post‐mortem detection of M. agalactiae in cases of clinical mastitis as well as being a useful tool for the study of the route of infection and cellular types involved during mastitis caused by this organism.     

Presentation of postweaning Escherichia coli diarrhea in southern Ontario, prevalence of hemolytic E. coli serogroups involved, and their antimicrobial resistance patterns

Post-weaning Escherichia coli diarrhea (PWECD) in Ontario was investigated using a case-control study involving 50 Ontario nurseries. The clinical signs and the impact on productive parameters were determined by means of a producer survey. The hemolytic E. coli serogroups involved in PWECD (O149:K91:K88) were examined in this study. Based on a polymerase chain reaction test, the hemolytic E. coli from 82% of the case herds were positive for 3 enterotoxins (STa, STb, and LT), those from 12% of the case herds were positive for STb and LT only, and those from one herd (6%) were positive for 3 enterotoxins, as well as for verotoxin and F18 pili. The E. coli involved in disease were resistant to multiple antibiotics. Case farms commonly used a wide variety of antibiotics either in the feed or water, or as injectable drugs. The most common antibiotic used to treat PWECD on the study farms was apramycin, but evidence of resistance to this antibiotic was noted. The PWECD problem was commonly seen within a week of weaning but onset of diarrhea was reported as late as the grower-finisher stage. Growth rate was poorer in case herds and mortality was higher than in control herds, demonstrating that PWECD is an economically important disease in Ontario.     

Effect of concentrate crude protein level on grass silage intake, milk yield and nutrient utilisation by dairy cows in early lactation.

Twenty-one multiparous dairy cows were fed concentrates containing three levels (119, 154 and 191 g/kg DM) of crude protein (CP) during the first ten weeks of lactation. Part of the grain and molassed sugar beat pulp was substituted with 0% (RSM0), 15% (RSM15) or 30% (RSM30) repeseed meal. Wilted grass silage was fed ad libitum after calving. The average response between RSM0 and RSM15 was +1.66 kg milk/d per percentage unit change in concentrate CP content. No further response occurred between RSM15 and RSM30. The positive effect of RSM inclusion was seen throughout the experimental period and was associated with increased plasma non esterified fatty acids (NEFA) and decreased plasma insulin concentration one week after calving, and higher efficiency of metabolisable energy utilisation for milk production. Digestibility of the diet remained unaffected. Milk and plasma urea tended to increase with RSM30 indicating excessive supply of rumen degradable protein. Because of the limited potential of cows to compensate for a deficit in feed protein supply by mobilising tissue protein, a substantial milk yield response can be achieved with a moderate level of protein supplementation during early lactation.     

Application and crop safety parameters for soil fumigants

Metam sodium alone and in combination with 1,3-dichloropropene plus 17% chloropicrin (1,3-D+C-17) were evaluated under polyethylene mulch film as alternatives for methyl bromide in tobacco and tomato transplant production for both efficacy against pests and crop safety. Eight different weed species, 10 genera or species of fungi and several agronomic criteria were evaluated at three different sites. In general both the metam sodium alone and in combination with 1,3-D+C-17 were highly efficacious when compared to methyl bromide. Short polyethylene film retention times and short aeration times resulted in poor stands and poor crop vigor while relatively long polyethylene film retention times and long aeration periods at the same rates typically resulted in high stand counts and vigor. Combination treatments were more phytotoxic to germinating seed of tobacco and tomato. Vigor and stand counts of the seedlings were higher as aeration time increased, suggesting phytotoxic residues dissipate with time. Method of application of metam sodium, either injected with chisels or sprayed onto the soil surface and incorporated with a tractor-powered tiller alone or co- applied with 1,3-D+C-17 chisel injected, did not affect the efficacy of the treatments. Caution regarding phytotoxicity must be exercised when seeding into soil fumigated with metam sodium alone or combined with 1,3-D+C-17. Additional work will be required to establish safety periods required prior to transplanting crops into fumigated soil.