Growth inhibition of environmental mastitis pathogens during physiologic transitions of the bovine mammary gland

Ten dairy cows were infused intramammarily near drying off with concanavalin A (conA) or phytohemagglutinin (PHA). Mammary secretions were collected during physiologic transitions of the udder and were used in an in vitro microbiological assay to determine growth inhibition of mastitis pathogens. As mammary involution progressed, in vitro growth inhibition of Klebsiella pneumoniae, Escherichia coli, and Streptococcus uberis increased. Mammary secretions from conA- and PHA-treated glands had significantly increased bacterial growth inhibition. Secretions contained significantly increased concentrations of lactoferrin and a decreased citrate:lactoferrin molar ratio earlier in the dry period than did control mammary secretions. Greatest bacterial growth inhibition was observed in mammary secretions obtained 7 days before parturition. However, differences in secretion composition or bacterial growth inhibition were not found between conA- or PHA-treated and control udder halves during the prepartum period. Bacterial growth inhibition by mammary secretion decreased markedly during early lactation. A highly significant positive correlation was found between bacterial growth inhibition and concentrations of lactoferrin, serum albumin, and immunoglobulin G. A highly significant negative correlation was found in the citrate:lactoferrin molar ratio during early involution and the peripartum period.     

Spherocytosis associated with anaplasmosis in two cows

Spherocytes were detected on blood smears of 2 Angus cows. The RBC from both cows had increased fragility in hypotonic saline solution, supporting the presence of spherocytes. Other laboratory tests revealed a macrocytic, regenerative anemia with anisocytosis, polychromasia, basophilic stippling, Howell-Jolly bodies, nucleated RBC, and Anaplasma marginale organisms. A complement-fixation test was positive for anaplasmosis in cow 1 and a direct Coombs' test was positive for immunoglobulin G in both cows.     

Determination of amino acid digestibility using caecectomised and intact adult cockerels

Four subsamples of meat and bone meal (MBM) were heated (150 degrees C) for 0, 1.5, 3 and 5 h and then incorporated into four individual diets (100 g MBM/kg diet). The diets were precision-fed to 10 caecectomised and 10 intact adult cockerels. The apparent amino acid digestibility (ApAAD) and true amino acid digestibility (TAAD) of the diets were determined by analysis of the excreta. The digestibility coefficients measured using caecectomised birds were lower than those determined with intact birds. Coefficients of digestibility were statistically examined by analysis of variance for the effects of bird type (caecectomised or intact), type of calculation (apparent or true) and diet (heat-treatment) with and without accommodation for individual bird variability. If individual bird variability was not considered in the analysis the bird type X diet interactions (P less than 0.01) included glutamic acid, tyrosine and serine. When individual bird variability was included in the analysis, significant (P less than 0.01) bird type X diet interactions occurred for aspartic acid, serine, glutamic acid, leucine, tyrosine and lysine and the precision of the data was markedly improved. Amino acid digestibility using the precision-feeding procedure is affected by the selection of either intact or caecectomised birds.     

Body condition of sows across parities and relationship to reproductive performance

Weight, heartgirth, backfat and body condition of sows was monitored in a commercial, farrow-to-finish unit during 1 yr. Measurements were obtained during the third, ninth and fifteenth week of gestation and the day after weaning. Litter performance and rebreeding rate also were recorded. Body weight and heartgirth increased (P less than .01) over parities because gestational gains were larger than lactational losses. Backfat tended to be lower in later parities. Body weight, heartgirth and backfat, but not condition score, declined from weaning to the third week of the subsequent gestation in both first and second litter sows. Correlations among measures of body condition were low (less than .45), except the overall correlation between body weight and heartgirth. Number of pigs born alive increased and interval to estrus decreased in later parities. There were no significant relationships between changes in body condition and rebreeding performance of sows. These results suggest that changes in body condition typically observed in sows housed in commercial production units may be too subtle to have an effect on reproductive performance.     

Characteristics of cerebrospinal fluid associated with canine granulomatous meningoencephalomyelitis: a retrospective study

Cerebrospinal fluid of 22 dogs with histologically confirmed granulomatous meningoencephalomyelitis was analyzed, retrospectively. Seventeen dogs had cisternal CSF analysis, 4 dogs had lumbar CSF analysis, and 1 dog had both. For cisternal CSF, the mean +/- SEM total WBC count was 800.8 +/- 300.9 cells/microliter. The WBC differential count was predominantly lymphoplasmacytic cells, but 13 of the 18 cisternal CSF had polymorphonuclear (PMN) cells, and the mean +/- SEM PMN cell percentage was 18.6 +/- 5.3%. The mean +/- SEM total protein content of cisternal CSF was 255.8 +/- 98 mg/dl. Of 5 cisternal CSF pressures measured, 4 were within the normal range. The mean +/- SEM total WBC count and total protein content of lumbar CSF were 533.4 +/- 256.5 cells/mu/microliter and 163.2 +/- 25 mg of protein/dl, respectively. As with cisternal CSF, the WBC differential count of lumbar CSF was predominantly lymphoplasmacytic cells. Of 5 lumbar CSF, 4 contained PMN cells, but the percentage was less than the PMN cell percentage of cisternal CSF. Although variable, the general pattern of CSF abnormality associated with granulomatous meningoencephalomyelitis was different from the CSF abnormalities commonly seen with viral, bacterial, or mycotic encephalitides.     

Characteristics of Salmonella isolated from animals at a veterinary medical teaching hospital

Salmonella belonging to 47 serotypes was isolated from animals at the University of California Veterinary Medical Teaching Hospital during the years 1974 to 1983. Salmonella belonging to 12 serotypes accounted for 89% of the 725 isolates. Salmonella typhimurium (including var copenhagen) was the most commonly isolated serotype, but during 1981 to 1983, S krefeld and S saint-paul were predominant. Certain serotypes seemed to be isolated more frequently from extraintestinal sources (S typhi-suis, S dublin). Although resistance to ampicillin, kanamycin, neomycin, streptomycin, and sulfonamides was common (greater than 60% of the isolates were resistant), resistance to chloramphenicol, gentamicin, and trimethoprim-sulfonamides was infrequent, except for isolates of S krefeld and S saint-paul.     

Prevalence of canine uroliths. Minnesota Urolith Center

Uroliths obtained from 839 dogs were evaluated by quantitative methods. Struvite was the most prevalent mineral detected; newberyite, calcium oxalate, calcium phosphate, uric acid, sodium and ammonium urate, cystine, and silica were detected much less frequently. Seven per cent of the uroliths had an identifiable nucleus and one or more surrounding layers of different mineral types. Although uroliths were found in all parts of the urinary tract, the urinary bladder was most common. Uroliths of different composition were encountered in a variety of breeds of both sexes and different ages.     

Xenobiotic metabolism in suspensions and primary cultures of isolated hepatocytes prepared from the caudate process of bovine liver

Isolated hepatocytes were prepared from 100- to 125-kg Holstein male calves (n = 10) by perfusion of the caudate process of the caudate lobe of the liver. The 11th or 12th rib on the right side was resected to provide exposure of the caudate process. Complete postsurgical recovery of the donor from partial lobectomy was confirmed by growth data and serum chemical and hematologic criteria. Hepatocytes were isolated under aseptic conditions, using a 2-step collagenase vascular perfusion procedure. Hepatocyte preparations averaged 85% viability, and the yield averaged 1.2 X 10(7) viable hepatocytes/g of (wet weight) liver. Morphologic characteristics of hepatocytes examined under light and scanning electron microscopy were considered normal, except for occasional surface blebs. Freshly isolated hepatocytes in suspension rapidly decreased in viability and xenobiotic metabolizing capacity (aldrin epoxidation and ethoxycoumarin 0-deethylation and 7-hydroxycoumarin glucuronidation and sulfation), and hepatocytes surviving the initial 2 to 3 hours appeared to undergo repair. As an alternative, primary monolayer cultures on collagen-coated plates were evaluated. Hepatocytes attached to the collagen surface within 4 hours and appeared flattened by 12 hours. Although metabolic activity decreased about 30% over 8 hours in culture, the pattern of ethoxycoumarin metabolites was relatively constant. It was not determined to what extent the apparent loss of metabolic capacity was caused by hepatocyte detachment from the collagen surface. Although complicated by the requirement for asepsis, primary cultures were superior to suspensions for xenobiotic metabolism studies in cattle.     

Estimation of repeatability of blood constituents in gestating beef cattle on protein- and energy-restricted diets

Repeatabilities of blood constituents were calculated for 104 Angus heifers on two separate experiments fed adequate, protein-deficient, energy-deficient, or both protein- and energy-deficient diets. Four statistical methodologies were compared including analysis of variance, principal component (structural) analysis based on the sample covariance and sample correlation matrix, and maximum likelihood. Of 12 blood constituents tested only seven were considered sufficiently important to be included in the analysis. These blood constituents included blood urea nitrogen (BUN), creatinine (Creat), alkaline phosphatase (Alk Phos), total protein (T Prot), total bilirubin (T Bil), cholesterol (Chol) and Iron (Fe). If the standard linear model assumptions were met for heifers on the adequate diet, the estimators appeared to be quite similar for both years except when the correlation coefficient was relatively small. If the assumption of homogeneity of the variance-covariance matrix (compound symmetry) was relaxed, the structural analysis method based on the sample correlation matrix appeared preferable. However, when combining all diets, the maximum likelihood methodology was preferred. Among the specific blood constituents, Alk Phos had the highest repeatability, not only for the heifers on the adequate diet, but also for heifers on other treatments in both years. Repeatabilities for T Prot appeared to be the most consistent over all rations in both years. Repeatability estimates for Fe were high and relative rankings were consistent for both years, while repeatabilities for the other variables were either low and(or) inconsistent.