Effect of native Lactobacillus murinus LbP2 administration on total fecal IgA in healthy dogs

The objective of the present work was to determine the effect of Lactobacillus murinus strain LbP2 on canine fecal immunoglobulin A (IgA) levels. Seven dogs were orally treated with a 3-mL suspension of L. murinus LbP2 containing 5 × 10⁹ colony-forming units on alternate days for 2 wk. Six dogs were treated with 3 mL of phosphate-buffered saline as placebo. Fecal samples were taken from the rectal ampulla on days 0 and 16, and the total canine fecal IgA concentration was determined with an immunoperoxidase assay kit. The IgA levels of individual dogs were compared with the nonparametric Wilcoxon test. Differences were considered significant when the P-value was less than 0.05. An increase in the total fecal IgA concentration was observed in the 7 dogs after treatment with L. murinus LbP2 (P = 0.01796). No differences were detected between the initial total fecal IgA values and those obtained at the end of placebo treatment. Thus, after oral administration L. murinus LbP2 showed potential immunomodulatory effects, an important property to assess in a microorganism being considered for use as a probiotic.     

Effect of intestinal inflammation on fecal elastase concentration in dogs

BACKGROUND: A commercially available ELISA kit for fecal elastase measurement can be used in the diagnosis of exocrine pancreatic insufficiency (EPI) in dogs. However, other causes of diarrhea also may affect fecal elastase concentration. OBJECTIVE: This study was undertaken to determine whether intestinal inflammation alters fecal elastase concentration in dogs. METHODS: Fecal elastase concentration was measured with an ELISA kit in the following groups of dogs: group 1 (n=16), control dogs, without gastrointestinal disease; group 2 (n=14), dogs with diarrhea and no histopathologic evidence of intestinal inflammation; and group 3 (n=12), dogs with diarrhea and histopathologic evidence of intestinal inflammation. Serum trypsin-like immunoreactivity (TLI) was determined in dogs with diarrhea to rule out EPI. RESULTS: All dogs in groups 2 and 3 had serum TLI concentrations >5 microg/L, ruling out EPI. No statistically significant difference was found in fecal elastase concentration among the 3 groups of dogs (P=.969). CONCLUSIONS: The results indicate that intestinal inflammation does not affect fecal elastase concentration, such that test results may be used to exclude a diagnosis of EPI even in animals with inflammatory bowel disease.     

Development and analytic validation of a radioimmunoassay for the quantification of canine calprotectin in serum and feces from dogs

OBJECTIVE: To develop and analytically validate a radioimmunoassay (RIA) for the quantification of canine calprotectin (cCP) in serum and fecal extracts of dogs. Sample Population-Serum samples (n = 50) and fecal samples (30) were obtained from healthy dogs of various breeds and ages. PROCEDURES: A competitive, liquid-phase, double-antibody RIA was developed and analytically validated by assessing analytic sensitivity, working range, linearity, accuracy, precision, and reproducibility. Reference intervals for serum and fecal cCP concentrations were determined. RESULTS: Sensitivity and upper limit of the working range were 29 and 12,774 microg/L for serum and 2.9 and 1,277.4 microg/g for fecal extracts, respectively. Observed-to-expected ratios for serial dilutions of 6 serum samples and 6 fecal extracts ranged from 95.3% to 138.2% and from 80.9% to 118.1%, respectively. Observed-to-expected ratios for spiking recovery for 6 serum samples and 6 fecal extracts ranged from 84.6% to 121.5% and from 80.3% to 132.1%, respectively. Coefficients of variation for intra-assay and interassay variability were < 3.9% and < 8.7% for 6 serum samples and < 8.5% and < 12.6% for 6 fecal extracts, respectively. Reference intervals were 92 to 1,121 microg of cCP/L for serum and < 2.9 to 137.5 microg of cCP/g for fecal extracts. CONCLUSIONS AND CLINICAL RELEVANCE: The RIA described here was analytically sensitive, linear, accurate, precise, and reproducible for the quantification of cCP in serum and fecal extracts. This assay should facilitate research into the clinical use of serum and fecal cCP measurements in dogs with inflammatory bowel disease.     

Effects of dietary fructooligosaccharide on selected bacterial populations in feces of dogs

OBJECTIVE: To evaluate fecal concentrations of selected genera of colonic bacteria in healthy dogs, and to investigate effects of dietary fructooligosaccharides (FOS) on those bacterial populations. ANIMALS: 6 healthy adult Beagles. PROCEDURE: Dogs were randomly assigned to 2 groups of 3 and fed an unsupplemented diet for 370 days. After 88 days, fecal samples were collected. Another fecal sample was collected from each dog 282 days later. Group A then received a diet supplemented with FOS, and group B continued to receive the unsupplemented diet. Twenty-eight to 29 days later, fecal samples were collected. Diets were switched between groups, and fecal samples were collected 31 and 87 days later. Concentrations of Bifidobacterium spp, Lactobacillus spp, Clostridium spp, Bacteroides spp, and Escherichia coli in freshly collected feces were determined. Effects of diet and time on bacterial concentrations were compared between groups. RESULTS: Bifidobacterium spp and Lactobacillus spp were inconsistently isolated from feces of dogs fed either diet. Sequence of diet significantly affected number of Bacteroides spp subsequently isolated from feces, but diet had no effect on numbers of Clostridium spp or E coli. CONCLUSIONS AND CLINICAL RELEVANCE: Some genera of bacteria (eg, Bifidobacterium) believed to be common components of colonic microflora may be only sporadically isolated from feces of healthy dogs. This deviation from expected fecal flora may have implications for the effectiveness of supplementing diets with prebiotics.     

Serial plasma lactate concentrations in 68 puppies aged 4 to 80 days

Objective: To determine a reference range for venous blood lactate concentrations in healthy neonatal dogs. Design: A prospective cohort study. Setting: All work was conducted at the College of Veterinary Medicine, Texas A&M University. Animals: Clinically healthy dogs: 68 puppies and 30 adults. Measurements and main results: A blood sample was collected from each puppy into lithium heparin via jugular venipuncture at 4, 10, 16, 28, 70, and 80 days of age. A single venous sample was collected from each adult dog. Lactate concentration in each sample was measured immediately using an automated analyzer. Two hundred seventy‐seven blood samples were analyzed. Blood lactate concentrations of adult dogs were 1.80±0.84 mmol/L (mean±SD). Mean blood lactate concentrations of puppies were significantly higher at 4, 10, 16, and 28 days of age compared with those of adult dogs. The reference range for lactate concentration for puppies at 4 days of age was 1.07–6.59, and for the puppies from 10 to 28 days of age was 0.80–4.60. Conclusions: Assessment of perfusion can be challenging in neonates due to normal physiologic variation and small size. Measurement of lactate is rapid, minimally invasive, and has potential to be a useful marker of perfusion in neonatal dogs. However, lactate concentrations of neonatal dogs in this study were significantly higher than those of adult dogs. Reference ranges for venous lactate concentrations in adult dogs should not be used for puppies younger than 70 days of age.     

Effect of alternate-day prednisolone administration on hypophyseal-adrenocortical activity in dogs.

OBJECTIVE: To evaluate effect of alternate-day oral administration of prednisolone on endogenous plasma ACTH concentration and adrenocortical response to exogenous ACTH in dogs. ANIMALS: 12 Beagles. PROCEDURE: Dogs were allotted to 2 groups (group 1, 8 dogs treated with 1 mg of prednisolone/kg of body weight; group 2, 4 dogs given excipient only). During a 30-day period, blood samples were collected for determination of plasma ACTH and cortisol concentrations before, during, and after treatment with prednisolone. From day 7 to 23, prednisolone or excipient was given on alternate days. Sample collection (48-hour period with 6-hour intervals) was performed on days 1, 7, 15, 21, and 28; on other days, sample collection was performed at 24-hour intervals. Pre- and post-ACTH plasma cortisol concentrations were determined on days 3, 9, 17, 23, and 30. RESULTS: A significant difference was detected between treatment and time for group 1. Plasma ACTH concentrations significantly decreased for 18 to 24 hours after prednisolone treatment in group-1 dogs. At 24 to 48 hours, ACTH concentrations were numerically higher but not significantly different in group-1 dogs. Post-ACTH plasma cortisol concentration significantly decreased after 1 dose of prednisolone and became more profound during the treatment period. However, post-ACTH cortisol concentration returned to the reference range 1 week after prednisolone administration was discontinued. CONCLUSIONS AND CLINICAL RELEVANCE: Single oral administration of 1 mg of prednisolone/kg significantly suppressed plasma ACTH concentration in dogs for 18 to 24 hours after treatment. Alternate-day treatment did not prevent suppression, as documented by the response to ACTH.     

Effects of diet on fecal occult blood testing in healthy dogs.

Six dogs were fed each of nine diets to evaluate the effects of diet on fecal occult blood test results. The diets represented a range of different type (i.e. canned, dry or semi-moist), protein and vegetable constituents, and fiber contents. Each diet was fed twice daily for five consecutive days; fecal samples were collected twice daily on days 4 and 5. An o-tolidine test kit and a guaiac paper test kit for fecal occult blood were used. Two hundred and sixteen fecal samples were analyzed (24 samples/diet). When using the guaiac test the following positive results were obtained from fecal samples from dogs consuming a canned meat- and vegetable-based diet (24/24 samples); a canned meat-based diet (24/24 samples); a dry corn and poultry-based diet (9/24 samples); a dry corn, wheat, and meat meal diet (4/24 samples), a canned poultry-based diet (1/24 sample) and a semi-moist soybean meal-based diet (2/24 samples). A total of 64 samples were positive using the guaiac test. Using the o-tolidine test, no samples were positive. The difference between the number of positive results with each test kit was highly significant (p < 0.001). Results indicate that 1) diet affects the specificity of guaiac test fecal occult blood results in the dog and 2) positive o-tolidine test results were not caused by diets fed in the study.     

The development of a simple fecal immunoreactive progestin assay to monitor reproductive function in swine.

The objectives of the study were to (a) develop a simple fecal progestin extraction and radioimmunoassay method to measure immunoreactive progestin in porcine feces and (b) to characterize fecal progestin profiles during the estrous cycle and postpartum. A simple extraction method was developed in trial 1 and the mean (+/- SD) progestin recovery of the method was 84.3 +/- 3.5%. Progesterone levels measured at five different spiked concentrations (50, 100, 200, 400, and 500 ng/0.5 g feces) showed no systematic error. The sensitivity of the assay was 0.16 nmol/L of the extract. Trial 2 involved collecting fecal samples from six cycling sows every second or third day, beginning on the day of estrus (day 0) and continuing until day 22. The mean (+/- SD) fecal progestin concentrations of these sows determined by the above assay during days 0-5, days 6-10, days 11-15, and days 16-21 were 87.1 +/- 17.5, 262.6 +/- 102.1, 1188.2 +/- 454.1, and 897.3 +/- 274.1 x 10(-3) nmol/g feces, respectively. In trial 3, fecal samples from six postpartum sows were collected at weekly intervals beginning from day 7 after farrowing until day 50. The mean (+/- SD) fecal progestin concentrations were 111.0 +/- 61.1, 74.1 +/- 21.3, 66.5 +/- 26.1, 122.7 +/- 58.8 and 533.5 +/- 244.2 x 10(-3) nmol/g feces, during days 7-10, days 11-20, days 21-30, days 31-40, and days 41-50 postpartum, respectively. The results indicate that simple fecal progestin extraction and assay are feasible alternatives to the standard blood progesterone assays for monitoring reproductive function in swine.     

Development of nasal, fecal and serum isotype-specific antibodies in calves challenged with bovine coronavirus or rotavirus

Unsuckled specific pathogen free calves were inoculated at 3-4 weeks of age, either intranasally (IN) or orally (O) with bovine coronavirus or O plus IN (O/IN) or O with bovine rotavirus. Shedding of virus in nasal or fecal samples, and virus-infected nasal epithelial cells were detected using immunofluorescent staining (IF), ELISA or immune electron microscopy (IEM). Isotype-specific antibody titers in sera, nasal and fecal samples were determined by ELISA. Calves inoculated with coronavirus shed virus in feces and virus was detected in nasal epithelial cells. Nasal shedding persisted longer in IN-inoculated calves than in O-inoculated calves and longer than fecal shedding in both IN and O-inoculated calves. Diarrhea occurred in all calves, but there were no signs of respiratory disease. Calves inoculated with rotavirus had similar patterns of diarrhea and fecal shedding, but generally of shorter duration than in coronavirus-inoculated calves. No nasal shedding of rotavirus was detected. Peak IgM antibody responses, in most calves, were detected in fecal and nasal speciments at 7-10 days post-exposure (DPE), preceeding peak IgA responses which occurred at 10-14 DPE. The nasal antibody responses occurred in all virus-inoculated calves even in the absence of nasal shedding of virus in rotavirus-inoculated calves. Calves inoculated with coronavirus had higher titers of IgM and IgA antibodies in fecal and nasal samples than rotavirus-inoculated calves. In most inoculated calves, maximal titers of IgM or IgA antibodies correlated with the cessation of fecal or nasal virus shedding. A similar sequence of appearance of IgM and IgA antibodies occurred in serum, but IgA antibodies persisted for a shorter period than in fecal or nasal samples. Serum IgG1 antibody responses generally preceeded IgG2 responses and were predominant in most calves after 14-21 DPE.     

Development and analytic validation of an immunoassay for the quantification of canine S100A12 in serum and fecal samples and its biological variability in serum from healthy dogs

S100A12 (calgranulin C) is a Ca(2+)-binding protein that has been proposed to play a central role in both innate and acquired immune responses. In humans, S100A12 has been reported to be increased in serum and/or plasma in patients with various inflammatory disorders, and this protein has been suggested to be a sensitive and specific marker for inflammatory bowel disease (IBD). An immunoassay for S100A12 is currently available for use in humans, but antibodies against the human protein do not cross-react with canine S100A12 (cS100A12). Both sensitive and specific markers for canine patients with systemic or localized inflammatory diseases are currently lacking, thus the aim of this study was to develop and analytically validate a radioimmunoassay (RIA) for the quantification of cS100A12 in serum and fecal specimens and to determine the biological variation of cS100A12 in serum from healthy dogs. A competitive liquid-phase RIA was developed and analytically validated by determining assay working range, dilutional parallelism, spiking recovery, and intra- and inter-assay variability. Reference intervals for serum and fecal concentrations of cS100A12 were established from 124 and 65 healthy dogs, respectively, and components of variation for serum cS100A12 were determined from 11 dogs over 2.6 months. The working range of the assay was 0.6-432.7 μg/L. No cross-reactivity was observed with the cS100A8/A9 protein complex, the closest structural analogues available. Observed-to-expected ratios (O/E) for the serial dilution of serum and fecal extracts ranged from 97.2 to 146.8% and from 75.3 to 129.8%, respectively. O/E for spiking recovery for serum and fecal extracts ranged from 87.8 to 130.4% and from 84.8 to 143.8%, respectively. Coefficients of variation (CV) for intra- and inter-assay variability for sera were ≤ 8.1% and ≤ 7.8%, respectively, and were ≤ 7.8% and ≤ 8.7%, respectively, for fecal extracts. Reference intervals for serum and fecal cS100A12 were 33.2-225.1 μg/L and <24-745 ng/g, respectively. For biological variability testing, analytical, intra-individual, inter-individual, and total CV were 5.7, 29.2, 31.2, and 66.0%, respectively, yielding an index of individuality of 0.95 and a minimum critical difference (p<0.05) for sequential values of 84.9%. The RIA for cS100A12 measurement described here is analytically sensitive and specific, linear, accurate, precise, and reproducible, and will facilitate further research into the clinical utility of quantifying serum and fecal cS100A12 in canine patients with inflammatory diseases. Moderate changes in serum cS100A12 concentrations may be clinically relevant; however, the use of a population-based reference interval may require caution.     

Changes in fecal progestagen profile after excretion in miniature pigs

The aim of this study was to evaluate whether the fecal progestagen (progesterone and its metabolites) levels of miniature pigs would change after excretion at room temperature. Our initial investigation focused on the correlations between the fecal progestagen concentrations with and without ether extraction and between the plasma progesterone and fecal progestagen concentrations in order to develop an enzyme-linked immunosorbent assay (ELISA) for fecal progestagen without ether extraction. There were significant correlations between fecal progestagen concentrations with and without ether extraction (r=0.880) and between fecal progestagen concentrations without ether extraction and plasma progesterone (r=0.763). The fecal progestagen concentration obtained by ELISA without ether extraction was almost identical to that obtained with ether extraction. These results validate the ELISA method without ether extraction, which was therefore used for the latter experiment. Fecal samples collected from the pigs were preserved for 0-24 h at room temperature, and then their fecal progestagen concentrations were measured. The fecal samples preserved for 0 to 24 h were analyzed by high performance liquid chromatography (HPLC) and ELISA. The concentrations of all samples significantly increased with time after preservation. The progestagen concentration of fresh feces (0 h) with high progestagen concentration (>1000 ng/g) increased significantly after 3 h. The concentration increased significantly after 12 h for fresh feces containing about 500 ng/g progestagen. HPLC analysis is showed that the fecal progesterone concentration, but not its other metabolites, doubled 24 h after excretion compared with the concentration at 0 h. These results suggest that dynamic changes in the profile of progesterone metabolites occur in feces after excretion.     

Protein-losing enteropathy in dogs is associated with decreased fecal proteolytic activity

Background: Measurement of proteolytic activity in feces is a traditional method for the diagnosis of exocrine pancreatic insufficiency (EPI). A drawback of this method is the occurrence of falsely low results that may lead to a false‐positive diagnosis of EPI. We hypothesized that intestinal loss of serum proteinase inhibitors in protein‐losing enteropathy (PLE) may inhibit fecal proteolytic activity and be a potential source of false low results. Objective: The objective of this study was to determine the effect of PLE on fecal proteolytic activity in dogs. Methods: Fecal proteolytic activity was measured using a radial diffusion casein digestion assay in 12 samples from 4 clinically healthy control dogs and 30 samples from 16 dogs with PLE. Gastrointestinal protein loss was assessed using an ELISA to determine fecal canine α₁‐proteinase inhibitor concentration. The relationship between the concentration of canine α₁‐proteinase inhibitor in the feces and the diameter cleared in the casein digestion assay was determined. The mean clearing diameter was compared between control dogs and dogs with PLE. Results: A significant negative correlation was observed between fecal canine α₁‐proteinase inhibitor concentration and casein clearing diameter (P < .001, Pearson r=—.6317, r 2 =.3999). Mean clearing diameter was significantly lower in dogs with PLE than in control dogs (12.63 vs 16.83 mm, P < .001, two‐tailed Student's t‐test). Conclusion: Increased fecal loss of α₁‐proteinase inhibitor in dogs with PLE is associated with a significant decrease in fecal proteolytic activity and may result in a false positive diagnosis of EPI.     

Comparison of canine capillary and jugular venous blood lactate concentrations determined by use of an enzymatic-amperometric bedside system

OBJECTIVE: To evaluate the analytical agreement between blood lactate concentrations determined by use of an enzymatic-amperometric bedside system in capillary blood samples from the pinna and in jugular venous blood samples from dogs. ANIMALS: 53 dogs. PROCEDURES: For each dog, venous and capillary blood samples were obtained from a jugular vein and from the ear pinna (by use of a lancing device), respectively, following a randomized sequence of collection. Lactate concentrations in both types of samples were analyzed by use of an enzymatic-amperometric bedside system intended for lactate detection in capillary blood samples from humans that was previously validated in dogs. The Passing-Bablock regression analysis was used to compare venous and capillary blood lactate concentrations; the level of agreement was calculated by use of the Bland-Altman method. RESULTS: Jugular venous blood samples were collected without difficulty from all 53 dogs. A capillary blood sample was obtained from only 47 dogs. The correlation coefficient between lactate concentrations measured in venous and capillary blood samples was 0.58 (slope, 2.0 [95% confidence interval, 1.5 to 3.0]; intercept, -1.2 [95% confidence interval, -3.1 to 0.4]). The mean difference between methods was 0.72 mmol/L (95% confidence interval, 0.38 to 1.06) with limits of agreement of -1.55 to 2.99 mmol/L. CONCLUSIONS AND CLINICAL RELEVANCE: Because of the lack of agreement between lactate concentrations determined in capillary and jugular venous blood samples, measurement of capillary blood lactate concentration in dogs performed with the technique used in the study does not appear to be a reliable alternative to jugular venous blood measurements.     

Measurement of urinary glycosaminoglycans in dogs

OBJECTIVES: To measure urine concentrations of sulfated glycosaminoglycans (GAGs), determine optimal storage conditions for urine samples, establish a reference range, and determine whether there is correlation between 24-hour total urine GAG excretion and the GAG-to-creatinine ratio (GCR). ANIMALS: 14 healthy adult dogs. PROCEDURE: Single urine sample GAG concentrations and GCRs were measured in samples collected from 14 healthy dogs at the start of the 24-hour collection period. Twenty-four-hour total urine GAG excretions were determined from urine collected during a 24-hour period in the same 14 dogs. Total sulfated GAG concentrations were also measured in urine from these dogs after the urine had been stored at 4 degrees C and -20 degrees C for 1, 7, and 30 days. RESULTS: Urine GAG concentrations were not significantly different from baseline values after urine was stored at 4 degrees C for up to 1 day and -20 degrees C for up to 30 days. Neither single urine sample GAG concentration (R2, 0.422) nor GCR (R2, 0.084) was an adequate predictor of 24-hour total urine GAG excretion. CONCLUSIONS AND CLINICAL RELEVANCE: Results of this study provide data that can be used to establish a reference range for 24-hour total urine GAG excretion in dogs and adequate conditions for sample storage. Contrary to findings in humans, there was no significant linear correlation between 24-hour total urine GAG excretion and single urine sample GCR in dogs, limiting clinical use of the single urine sample test.     

Evaluation of bacteriologic culture of pooled fecal samples for detection of Mycobacterium paratuberculosis

OBJECTIVES: To compare sensitivity of several methods of bacteriologic culture of pooled bovine fecal samples for detection of Mycobacterium paratuberculosis and evaluate homogeneity in number of M paratuberculosis in pooled fecal samples. SAMPLE POPULATION: Feces from 10 dairy cows that shed M paratuberculosis at various concentrations and 1 dairy cow known to be free of infection with M paratuberculosis. PROCEDURE: 5 fecal pooling methods, 2 culture methods, and 2 pool sizes were evaluated. Each pooled sample contained 1 infected sample and 4 or 9 uninfected samples. RESULTS: Sensitivity of detection of M paratuberculosis was greater with smaller pool size (5 vs 10 samples/pool). Detection sensitivity was also associated with concentration of bacteria in the infected sample. Results indicated that, compared with concurrent bacterial culture of individual infected samples, 37 to 44% of pooled samples with low bacterial concentrations yielded positive culture results and 94% of pooled samples with high bacterial concentrations yielded positive results. CONCLUSIONS AND CLINICAL RELEVANCE: Bacteriologic culture of pooled fecal samples may provide a valid and cost-effective method of detecting M paratuberculosis infection in cattle herds.     

Comparison of insulin-like growth factor-I concentration in mammary secretions and serum of small- and giant-breed dogs.

OBJECTIVE: To determine insulin-like growth factor-I (IGF-I) concentrations in canine mammary secretions and serum during lactation and to compare them between small and giant breeds of dogs. ANIMALS: 7 gestating Beagles and 4 gestating Great Danes. PROCEDURE: Dogs were fed a common nutritionally complete and adequate gestation and lactation diet. Milk samples were collected at postpartum hour 12 and postpartum days 3, 7, 14, 21, and 28 after IV oxytocin administration. Two puppies/litter were identified at whelping for collection of blood samples corresponding to the days of milk sample collection plus days 35 and 42. Maternal blood samples were obtained on days 1, 7, and 42 from Beagles and days 1, 7, and 28 from Great Danes and were acid/ethanol extracted and analyzed by use of a radioimmunoassay. RESULTS: Maternal serum IGF-I concentration was greater in Great Danes at all sample collection times. Similarly, colostrum from Great Danes contained more IGF-I, compared with that of Beagles (70 ng/ml vs 40 ng/ml, respectively). These values decreased to approximately 10 ng/ml by day 3 in both breeds and remained between 10 and 20 ng/ml for the duration of lactation. Growth rate and serum IGF-I concentration were greater in Great Dane puppies at birth to day 42. CONCLUSIONS AND CLINICAL RELEVANCE: High IGF-I concentration in colostrum may be biologically important for newborn puppies. Body mass and serum IGF-I concentration are directly correlated in growing Beagle and Great Dane puppies. Serum IGF-I concentration may be an indicator of growth potential in dogs.     

Technical note: effectiveness of different methods of continuous marker administration for estimating fecal output.

Six ruminally fistulated crossbred steers (BW = 369 kg) were used in a randomized complete block experiment to test the efficacy of continuous-infusion pumps and controlled-release boluses for administering external markers to predict fecal output. Steers, limit-fed chopped alfalfa hay at 2% of BW daily, were fitted with continuous-infusion pumps that administered Co-EDTA and YbCl3 solutions intraruminally. In addition, a controlled-release bolus containing Cr2O3 was inserted into the rumen of each steer. Fecal grab samples were taken every 6 h for 7 d during initial marker equilibration; after this period, fecal grab samples were taken every 3 h for 48 h to evaluate diurnal variation patterns. Steers were subsequently fitted with fecal bags for 7 d to allow total fecal collection. Grab samples also were taken during the total fecal collection period at 0600 (AM) and 1400 (PM). The marker X time effect was nonsignificant. Similarly, time of grab sampling (AM or PM) did not affect estimates of fecal output (P greater than .10), but the Cr2O3 bolus overestimated fecal output (P less than .05). Fecal marker concentrations during the 48-h profile showed little diurnal variation regardless of marker used. All markers equilibrated in the feces at approximately 100 to 120 h after initiating infusions. The continuous-infusion pumps evaluated were efficacious for administering markers for estimating total fecal output in limit-fed steers; however, the Cr2O3 boluses evaluated overestimated fecal output when the manufacturer's suggested release rate was used for fecal output calculations.     

Quantification of cortisol, cortisol immunoreactive metabolites, and immunoglobulin A in serum, saliva, urine, and feces for noninvasive assessment of stress in reindeer

This study was designed to develop reliable methods for quantification of cortisol and cortisol immunoreactive metabolites (C-CIM) and immunoglobulin A (IgA) in reindeer serum, saliva, urine, and feces as tools for the objective noninvasive assessment of well-being and immunocompetence in reindeer. Although C-CIM was readily quantifiable by radioimmunoassay in serum, urine, and feces, the levels in saliva samples were low, rendering quantification unreliable. Whereas IgA concentrations were high in feces samples, they were much lower, albeit quantifiable, in serum and urine; the levels in saliva samples were too low for quantification with the use of an enzyme-linked immunosorbent assay that we developed. Further studies are in progress to validate the usefulness of fecal levels of C-CIM and IgA in the assessment of welfare in reindeer.     

Correlation of periovulatory serum and fecal progestins in the domestic dog.

This study was initiated to determine the relationship between canine ovarian steroids detected in serum and feces during the periovulatory interval in domestic dogs, and to examine the feasibility of a non-invasive method to estimate the time of ovulation in canid species. When bitches (n = 14) were observed to enter proestrus (based on vulvar enlargement or serosanguineous vaginal discharge), paired daily serum and fecal samples were collected for a 15- to 20-day period and stored at -20 degrees C. After extraction, progestin concentrations in both substrates were measured using an established enzyme immunoassay procedure. All samples were aligned to Day 0, the first day in which fecal progestins reached a sustained rise above 100 ng/g feces. Mean fecal progestin concentrations increased in parallel with mean serum progesterone values (r = 0.78), rising from 44.6+/-2.6 ng/g feces to 409.6+/-90.9 ng/g feces, and 5.4+/-0.9 nmol/L to 81.2+/-18.5 nmol/L, on Day -5 and Day 5, respectively. Individual fecal progestin concentrations varied markedly, but plotted against serum progesterone concentrations demonstrated correlation coefficients ranging from 0.41 to 0.97 (P<0.05). These results demonstrate that sequential changes in domestic dog serum ovarian steroid concentrations are paralleled in the feces, and that it is feasible to non-invasively monitor individual progestin changes in the periovulatory interval using fecal hormone analysis.     

Quantification of stress sensitive markers in single fecal samples do not accurately predict excretion of these in the pig

All feces produced during 24 h were collected from five pigs and cortisol and immunoreactive cortisol metabolites (CICM), and IgA were quantified. Within pigs, the concentrations of CICM and IgA varied extensively between random samples obtained from a single fecal dropping, and deviated in most cases significantly from the true concentration measured in total fecal output (CV 6.7-130%). The CICM and IgA contents varied considerably (CV 8.1-114%) within and between individual fecal droppings from the same pig compared to the total fecal excretion. In conclusion, single random samples could not be used to reliably quantify the total fecal concentration or excretion of CICM or IgA in pigs. Analyses of all feces collected during shorter periods than 24 h did not provide an accurate estimate of the daily excretion of CICM. Thus, the concentration of stress sensitive molecules in random single fecal samples as an indicator of animal welfare should be interpreted with prudence.