Comparison of pulmonary defense mechanisms in Rocky Mountain bighorn (Ovis canadensis canadensis) and domestic sheep

Alveolar macrophages were obtained from Rocky Mountain bighorn sheep (Ovis canadensis canadensis) and domestic sheep for the purpose of comparing pulmonary host defense mechanisms in the two species. Specific variables studied included (1) characterization of the cell types present in the lung, (2) alveolar macrophage phagocytic and bactericidal functions, (3) measurement of protein levels in lavage fluid, and (4) measurement of cortisol levels in lavage fluid. While phagocytic cell populations were similar between bighorn and domestic sheep, a significantly higher percentage of lymphocytes were present in bighorns than domestics (20% in bighorn versus 6% in domestic sheep). Significant differences were not observed in the phagocytic or bactericidal functions of macrophages between the two species. Significant differences were not observed in either lavage fluid protein levels or in cortisol levels.     

A bighorn sheep die-off in southern Colorado involving a Pasteurellaceae strain that may have originated from syntopic cattle

We investigated a pasteurellosis epizootic in free-ranging bighorn sheep (Ovis canadensis) wherein a Pasteurellaceae strain carried by syntopic cattle (Bos taurus) under severe winter conditions appeared to contribute to pneumonia in affected bighorns. Twenty-one moribund or dead bighorn sheep were found on the "Fossil Ridge" herd's winter range, Colorado, USA, between 13 December 2007 and 29 February 2008. Eight carcasses examined showed gross or microscopic evidence of acute to subacute fibrinous bronchopneumonia. All eight carcasses yielded at least one β-hemolytic Mannheimia haemolytica biogroup 1(±(G)) strain, and seven also yielded a β-hemolytic Bibersteinia trehalosi biogroup 4 (CDS) strain; evidence of Pasteurella multocida, Mycoplasma ovipneumoniae, and parainfluenza 3 and bovine respiratory syncytial viruses was also detected. Isolates of β-hemolytic Manneimia haemolytica biogroup 1(G) from a bighorn carcass and a syntopic cow showed 99.5% similarity in genetic fingerprints; B. trehalosi biogroup 4(CDS) isolates were ≥94.9% similar to an isolate from a nearby bighorn herd. Field and laboratory observations suggested that pneumonia in affected bighorns may have been caused by a combination of pathogens including two pathogenic Pasteurellaceae strains--one likely of cattle origin and one likely of bighorn origin--with infections in some cases perhaps exacerbated by other respiratory pathogens and severe weather conditions. Our and others' findings suggest that intimate interactions between wild sheep and cattle should be discouraged as part of a comprehensive approach to health management and conservation of North American wild sheep species.     

Effects of delivery method on serological responses of bighorn sheep to a multivalent Pasteurella haemolytica supernatant vaccine

The safety and efficacy of a remotely delivered multivalent Pasteurella haemolytica supernatant vaccine (serotypes A2 and T10) were examined in captive Rocky, Mountain bighorn sheep (Ovis canadensis canadensis). Twenty bighorn sheep were grouped according to baseline leukotoxin neutralizing antibody titers (< or =2 or >2 log2(-1)) and vaccination history (previously vaccinated or unvaccinated). Within these groups, animals were randomly assigned to one of two delivery treatments: hand injection (control) or biobullet implantation. All bighorns received a single dose from the same lot of vaccine (n = 10/treatment); four additional animals were injected intramuscularly with 0.9% saline as unvaccinated sentinels. Mild, transient lameness one day after hand injection or biobullet implantation was the only adverse effect. Serum neutralizing antibody titers to P. haemolytica leukotoxin differed between delivery treatments (P = 0.009) and among baseline titer/vaccination history groups (P = 0.013). Neutralizing titers were higher among hand-injected bighorns. Although neutralizing titers were lower among implanted bighorns than hand-injected controls at 1 wk (P = 0.002) and 2 wk (P = 0.021) after vaccination, seroconversion rates in response to implantation (6/10) and hand injection (9/10) did not differ (P = 0.303). Agglutinating antibody titers to T10 were high and did not vary over time or between delivery treatments. Agglutinating antibody titers to A2 in the hand-injected controls were not different (P > or = 0.07) than those in bighorns vaccinated with biobullet implantation. These data demonstrate that although hand injection elicits higher absolute titers, biobullet implantation may also stimulate effective antibody responses to P. haemolytica supernatant vaccine. Further evaluation of biobullet vaccination against pneumonic pasteurellosis in free-ranging populations of wild bighorn sheep is warranted.     

Epidemic pasteurellosis in a bighorn sheep population coinciding with the appearance of a domestic sheep

A pneumonia epidemic reduced bighorn sheep (Ovis canadensis) survival and recruitment during 1997-2000 in a population comprised of three interconnected wintering herds (Kenosha Mountains, Sugarloaf Mountain, Twin Eagles) that inhabited the Kenosha and Tarryall Mountain ranges in central Colorado, USA. The onset of this epidemic coincided temporally and spatially with the appearance of a single domestic sheep (Ovis aires) on the Sugarloaf Mountain herd's winter range in December 1997. Although only bighorns in the Sugarloaf Mountain herd were affected in 1997-98, cases also occurred during 1998-99 in the other two wintering herds, likely after the epidemic spread via established seasonal movements of male bighorns. In all, we located 86 bighorn carcasses during 1997-2000. Three species of Pasteurella were isolated in various combinations from affected lung tissues from 20 bighorn carcasses where tissues were available and suitable for diagnostic evaluation; with one exception, beta-hemolytic mannheimia (Pasteurella) haemolytica (primarily reported as biogroup 1(G) or 1(alphaG)) was isolated from lung tissues of cases evaluated during winter 1997-98. The epidemic dramatically lowered adult bighorn monthly survival in all three herds; a model that included an acute epidemic effect, differing between sexes and with vaccination status, that diminished linearly over the next 12 mo best represented field data. In addition to the direct mortality associated with epidemics in these three herds, lamb recruitment in years following the pneumonia epidemic also was depressed as compared to years prior to the epidemic. Based on observations presented here, pasteurellosis epidemics in free-ranging bighorn sheep can arise through incursion of domestic sheep onto native ranges, and thus minimizing contact between domestic and bighorn sheep appears to be a logical principle for bighorn sheep conservation.     

Fecal corticosterone reflects serum corticosterone in Florida sandhill cranes

Florida sandhill cranes (Grus canadensis pratensis) were conditioned to confinement 6 hr/day for 7 days. On day 8, each bird's jugular vein was catheterized, blood samples were drawn, and each crane was confined for 6 hr. Using a randomized, restricted cross-over design, cranes were injected intravenously with either 0.9% NaCl solution or ACTH (cosyntropin; Cortrosyn; 0.25 mg). During the 6 hr of confinement, fecal samples (feces and urine) were collected from each of five cranes immediately after defecation. Individual fecal samples were collected approximately at hourly intervals and assayed for corticosterone. We showed previously that serum corticosterone did not vary significantly following saline injection, but peaked significantly 60 min after ACTH injection. Maximal fecal corticosterone concentrations (ng/g) were greater (P < 0.10; median 1087 ng/g) following ACTH stimulation compared to maximal fecal corticosterone concentrations at the end of acclimation (day 7; median 176) and following saline treatment (median 541). In cranes under controlled conditions, fecal corticosterone concentration reflects serum corticosterone levels, fecal corticosterone, Grus canadensis pratensis, sandhill cranes, serum corticosterone levels.     

Occurrence, diagnosis, and strain typing of Mycobacterium avium subspecies paratuberculosis infection in Rocky Mountain bighorn sheep (Ovis canadensis canadensis) in southwestern Alberta

The role that wildlife may play in the transmission of Mycobacterium avium subspecies paratuberculosis (Map), the causative agent of Johne's disease (JD), and the potential consequences of infection in these populations are being given increasing consideration. A yearling male Rocky Mountain bighorn sheep (Ovis canadensis canadensis) from southwestern Alberta, Canada, was found infected with Map in August 2009. Clinical signs of emaciation and diarrhea and histologic findings of diffuse granulomatous enteritis of the distal ileum, lymphadenitis of the mesenteric lymph nodes, and lymphangitis of the ileum were similar to previously described cases of JD in bighorn sheep. Infection with Map was confirmed by bacterial isolation through fecal culture, acid-fast staining, and polymerase chain reaction (PCR) of IS900. The Map1506 gene was sequenced, and the isolate was identified as a Cattle (Type II) strain. In a follow-up herd-level survey, three of 44 fecal samples (7%) from individual bighorn sheep from the same herd as the index case were PCR-positive and identified as Type II Map strains. Twenty-five samples from a distant bighorn population were negative. Additional strain typing of the isolates from the index case and the positive fecal samples was done by sequencing three discriminatory short sequence repeat (SSR) regions. All four SSR profiles differed from one another, suggesting multiple introductions or a long-existing circulation of Map within this bighorn population. Detailed molecular analyses are essential for understanding and managing diseases at the wildlife-livestock interface.     

Detecting nonhemolytic Pasteurella haemolytica infections in healthy Rocky Mountain bighorn sheep (Ovis canadensis canadensis): influences of sample site and handling

Effects of sampling procedures on ability to culture Pasteurella spp. from Rocky Mountain bighorn sheep (Ovis canadensis canadensis) were examined experimentally. Sample site influenced (P less than 0.0001) recovery of P. haemolytica in adult bighorn sheep. We isolated nonhemolytic P. haemolytica from 18 of 19 tonsillar swabs and 18 of 19 tonsillar biopsies from adult sheep, yet only four of 19 nasal swabs yielded isolates. Sample handling also affected (P less than 0.0001) recovery of P. haemolytica. Nonhemolytic P. haemolytica was cultured from 14 of 19 tonsillar swabs plated directly onto blood agar, but from only two of 19 swabs stored for 24 hr in modified Stuart's medium. We detected nonhemolytic P. haemolytica at least once in bronchial aspirates from four and in nasal swabs from three of six bighorn lambs. Based on direct cultures of tonsillar swabs and/or biopsies, all 26 bighorn sheep (seven lambs, 19 adults) sampled were infected with nonhemolytic P. haemolytica; only two lambs developed pneumonia during the study period. Thirty-four of 37 nonhemolytic P. haemolytica isolates tested were biotype T; three were biotype A. Serotypes 3; 4; 3, 4 and 3, 4, 10 were identified in a subsample of 17 isolates. Our data suggest tonsillar swabs or biopsies plated directly onto blood agar and incubated immediately offer the greatest probability of recovering nonhemolytic P. haemolytica from health bighorn sheep.     

Development of nine new microsatellite loci for the American beaver, Castor canadensis (Rodentia: Castoridae), and cross-species amplification in the European beaver, Castor fiber

We developed nine new nuclear dinucleotide microsatellite loci for Castor canadensis. All loci were polymorphic, except for one. The number of alleles ranged from two to four and from five to 12 in populations from Arizona and Wisconsin, respectively. Average heterozygosity ranged from 0.13 to 0.86 per locus. Since cross-species amplification in Castor fiber was successful only in four loci, we tested also nine recently published C. canadensis loci in the Eurasian species. Eight of the published loci amplified; however, three were monomorphic. The number of alleles was lower in C. fiber than in C. canadensis at all loci tested.     

Impact of zoo visitors on the fecal cortisol levels and behavior of an endangered species: Indian blackbuck (Antelope cervicapra L.)

This study investigated behavioral activities (resting, moving, aggressive, social, and reproductive behavior) and fecal cortisol levels in 8 individually identified adult male blackbucks during periods of varying levels of zoo visitors (zero, low, high, and extremely high zoo visitor density). This study also elucidated whether zoo visitor density could disturb nonhuman animal welfare. This study analyzed fecal cortisol from the samples of blackbuck by radioimmunoassay and found significant differences (p < .05) for time the animals devoted to moving, resting, aggressive, reproductive, and social behavior on days with high and extremely high levels of zoo visitors. The ANOVA with Duncan's Multiple Range Test test showed that the fecal cortisol concentration was higher (p < .05) during the extremely high (137.30 ± 5.88 ng/g dry feces) and high (113.51 ± 3.70 ng/g dry feces) levels of zoo visitor density. The results of the study suggest that zoo visitor density affected behavior and adrenocortical secretion in Indian Blackbuck, and this may indicate an animal welfare problem.     

Comparison of three fecal steroid metabolites for pregnancy detection used with single sampling in bighorn sheep (Ovis canadensis)

We conpared three fecal steroid metabolite assays for their usefulness in detecting pregnalcy among free-ranging Rocky Mountain bighorn sheep (Ovis canadensis canadensis) from Bighorn Canyon National Recreation Area, Wyoming and Montana (USA) and captive bighorn ewes at ZooMontana in Billings, Montana. Fecal samples were collected from 11 free-ranging, radio-collared bighorn ewes in late January-May 2001 and from 20 free-ranging, radio-collared ewes in late March to mid-May 2002. Free-ranging ewes were monitored the following spring to determine whether or not they lambed. In addition, two captive ewes were studied at ZooMontana. With three exceptions, free-ranging bighorn ewes that produced lambs had nonspecific progesterone metabolite (iPdG) levels of >1800 ng/g feces and iPdG levels >7000 ng/gm feces when samples were collected between early March and mid-May. Samples collected earlier in the year were inconclusive. One false negative was suspected to be the result of sample collection error. Of the captive ewes, nonspecific pregnanediol-3alpha-glucuronide (PdG) and iPdG followed a predictable curve over the course of the 180-day pregnancies. We conclude that estrone conjugates are not useful in diagnosing pregnancy; however, fecal steroid analysis of PdG and iPdG can be used to accurately determine pregnancy and reproductive function in bighorn sheep. This holds great potential as a noninvasive technique for understanding the role of reproductive disease in wild bighom sheep.     

Impact of Zoo Visitors on the Fecal Cortisol Levels and Behavior of an Endangered Species: Indian Blackbuck (Antelope cervicapra L.)

This study investigated behavioral activities (resting, moving, aggressive, social, and reproductive behavior) and fecal cortisol levels in 8 individually identified adult male blackbucks during periods of varying levels of zoo visitors (zero, low, high, and extremely high zoo visitor density). This study also elucidated whether zoo visitor density could disturb nonhuman animal welfare. This study analyzed fecal cortisol from the samples of blackbuck by radioimmunoassay and found significant differences (p < .05) for time the animals devoted to moving, resting, aggressive, reproductive, and social behavior on days with high and extremely high levels of zoo visitors. The ANOVA with Duncan's Multiple Range Test test showed that the fecal cortisol concentration was higher (p < .05) during the extremely high (137.30 ± 5.88 ng/g dry feces) and high (113.51 ± 3.70 ng/g dry feces) levels of zoo visitor density. The results of the study suggest that zoo visitor density affected behavior and adrenocortical secretion in Indian Blackbuck, and this may indicate an animal welfare problem.     

Renal function and fractional clearances of American river otters (Lutra canadensis)

The finely lobulated kidneys of American river otters (Lutra canadensis) are not visualized on plain abdominal radiographs. Similar values for blood urea nitrogen (BUN), creatinine, and uric acid were obtained on different analytical systems used in 1984 and 1985. The mean +/- SD for measured plasma osmolalities (309.80 +/- 8.86 mOsmol/kg) of otters in 1985 was significantly (P less than 0.01) less than that of calculated serum osmolalities in the same 1985 specimens (321.61 +/- 5.64 mOsmol/kg) and in 1984 specimens (322.20 +/- 7.16 mOsmol/kg). Urine specific gravities and osmolalities were highly correlated (r = 0.92). On routine urinalysis, protein and bilirubin were frequent chemical findings, and urobilinogen was present in all urine samples. White and red blood cells and epithelial cells were frequent findings on urine microscopic examinations. Proteus mirabilis was cultured from four of four female otters with genitourinary infections. The mean +/- SD creatinine values for paired serum and urine samples (n = 13) were serum creatinine (Scr) 0.66 +/- 0.09 mg/dl and urine creatinine (Ucr) 186.9 +/- 55.6 mg/dl. Corresponding values for serum electrolytes (Se) and urine electrolytes (Ue) yielded mean +/- SD calculated renal fractional clearances (FC = Ue/Se x Scr/Ucr) of sodium 9.65 +/- 5.81 x 10(-4), potassium 4.15 +/- 2.01 x 10(-2), chloride 10.81 +/- 5.33 x 10(-4), calcium 4.52 +/- 4.46 x 10(-3), and phosphate 6.58 +/- 3.44 x 10(-3).     

A non-invasive technique for analyzing fecal cortisol metabolites in snowshoe hares (<Emphasis Type="Italic">Lepus americanus</Emphasis>)

To develop non-invasive techniques for monitoring steroid stress hormones in the feces of free-living animals, extensive knowledge of their metabolism and excretion is essential. Here, we conducted four studies to validate the use of an enzyme immunoassay for monitoring fecal cortisol metabolites in snowshoe hares (Lepus americanus). First, we injected 11 hares with radioactive cortisol and collected all voided urine and feces for 4 days. Radioactive metabolites were recovered predominantly in the urine (59%), with only 8% recovered in the feces. Peak radioactivity was detected an average of 3.5 and 5.7 h after injection in the urine and feces, respectively. Second, we investigated diurnal rhythms in fecal cortisol metabolites by measuring recovered radioactivity 2 days after the radioactive cortisol injection. The total amount of radioactivity recovered showed a strong diurnal rhythm, but the amount of radioactivity excreted per gram of feces did not, remaining constant. Third, we injected hares with dexamethasone to suppress fecal cortisol metabolites and 2 days later with adrenocorticotropic hormone to increase fecal cortisol metabolites. Dexamethasone decreased fecal cortisol metabolites concentrations by 61% and adrenocorticotropic hormone increased them by 1,000%, 8–12 h after injection. Fourth, we exposed hares to a simulated predator (dog). This increased the fecal cortisol metabolites concentrations by 175% compared with baseline concentrations 8–12 h after exposure. Thus, this enzyme immunoassay provides a robust foundation for non-invasive field studies of stress in hares.     

Noninvasive monitoring of fecal cortisol metabolites in the eastern chipmunk (Tamias striatus): validation and comparison of two enzyme immunoassays

Monitoring fecal glucocorticoid metabolites in wild animals, using enzyme immunoassays, enables the study of endocrinological patterns relevant to ecology and evolution. While some researchers use antibodies against the parent hormone (which is typically absent from fecal samples), others advocate the use of antibodies designed to detect glucocorticoid metabolites. We validated two assays to monitor fecal cortisol metabolites in the eastern chipmunk (Tamias striatus). We compared an antibody produced against cortisol and one produced against 5α-pregnane-3β, 11β, 21-triol-20-one using a radiometabolism study and an injection with adrenocorticotropic hormone (ACTH). Most cortisol metabolites were excreted in the urine (～83%). Peak excretion in the feces occurred 8 h after injection. Both assays detected an increase in fecal cortisol metabolite levels after injection of ACTH. Males, but not females, exhibited a circadian variation in metabolite levels. The sexes did not exhibit any difference over the time course and route of excretion or the relative increase in fecal cortisol metabolite levels after ACTH injection. The cortisol assay displayed higher reactivity to ACTH injection relative to baseline than did the metabolite assay. While both antibodies gave comparable results, the cortisol antibody was more sensitive to changes in plasma cortisol levels in eastern chipmunks.     

Using Bedtime (pm) and early Morning (am) urine cortisol/creatinine ratios to evaluate pituitary-adrenal function in an office practice

ObjectiveTo evaluate the use of cortisol/creatinine ratios in urine specimens collected at bedtime (pm) and the following morning (am) in a general endocrine practice as a means of assessing pituitary-adrenal function in normal volunteers, outpatients with symptoms but no clinical endocrine dysfunction, patients with Cushing syndrome, and patients with known hypopituitarism.MethodsDouble-voided pm and am urine samples were collected from 26 healthy control subjects and 131 outpatients who had complaints of fatigue and malaise, inability to lose weight, or nonspecific concerns about potential underlying problems with their metabolism. The findings on physical examination and laboratory studies were normal in each of these outpatients. Urine was assayed for free cortisol and creatinine and expressed as ng of cortisol/mg of creatinine. Eleven patients with documented Cushing syndrome also collected urine specimens, and data for 11 patients with known hypopituitarism were also studied.ResultsA clear diurnal pattern of low cortisol excretion at night that increased some 7-fold in the morning (P < .0001) was reproducibly identified in healthy control subjects and those outpatients with no clinical endocrine disease. In the healthy control subjects, the mean PM urine cortisol/creatinine ratio was 15.8 (95% confidence interval [CI], 12.5 to 19.0); the mean AM cortisol/creatinine was 91.5 (95% CI, 65.0 to 118.0). The mean AM/pm ratio was 6.9, and the mean difference in AM - pm was 75.7. In the outpatients, there was no significant difference in pm, AM, AM/ pm, and AM - pm values in comparison with those in healthy control subjects, and no significant difference was noted in these variables among the 3 groups of outpatients (those with fatigue, weight gain, and metabolism concerns). In 11 patients with Cushing syndrome, the mean pm urine cortisol/creatinine ratio was 127.0 (95% CI, 87.0 to 166.0), and there was loss of diurnal variation with the AM/pm ratio of 1.16 (95% CI, 0.98 to 1.35). Patients with hypopituitarism had little to no increase in am urine cortisol/creatinine in comparison with pm urine cortisol/creatinine.ConclusionDetermination of pm and am urine cortisol/creatinine ratios offers a convenient method for assessing pituitary-adrenal function. (Endocr Pract. 2011;17: 591-597)     

Plague as a mortality factor in Canada lynx (Lynx canadensis) reintroduced to Colorado

As part of a species recovery program, 129 Canada lynx (Lynx canadensis) originating from British Columbia, the Yukon, Manitoba, and Quebec, Canada, and Alaska, USA, were reintroduced to southwestern Colorado, USA, from 1999 to 2003. Of 52 lynx mortalities documented by October 2003, six lynx, including a female and her 5-mo-old kitten, had evidence of Yersinia pestis infection as determined by fluorescent antibody test and/or culture. Postmortem findings in these lynx were characterized by pneumonia, ranging from acute suppurative pneumonia, to multifocal necrotizing pneumonia, to fibrinous bronchopneumonia. Histopathologic examination of lung revealed multiple areas of inflammation and consolidation, areas of edema and hemorrhage, and bacteria surrounded by extensive inflammation. Spleens had severe lymphoid depletion and hypocellular red pulp. Lymphadenomegaly was observed in only one plague-affected lynx. We hypothesize that these Canada lynx were exposed to Y. pestis by infected prey, and these are the first reports of plague in this species.     

Reproductive endocrine responses to photoperiod and exogenous gonadotropins in the pallas' cat (Otocolobus manul)

Fecal samples were collected for 14–26 months from three male and six female Pallas' cats (Otocolobus manul) to examine gonadal steroidogenic activity in response to changes in photoperiod and treatment with exogenous gonadotropins. Females exhibited a seasonal anestrus from May–December, excreting consistently low concentrations of fecal estrogens (overall mean, 50.2±8.5 ng/g). During the breeding season (January–April), baseline fecal estrogen concentrations were higher, averaging 128.4±18.9 ng/g, with peak concentrations ranging from 455.8–909.6 ng/g. Interpeak intervals in estrogen excretion ranged between 7 and 21 days, with an average estrous cycle length of 14.3±1.7 days. Two females became pregnant after natural mating, with overall luteal progestogen concentrations averaging ～40 μg/g throughout gestation. Fecal estrogens increased in mid‐gestation, peaking just before birth. Induction of follicular development with eCG (100–300 IU, i.m.) resulted in an increase in fecal estrogens (peak range, 263.1–1198.1 ng/g), followed by a postovulatory increase in fecal progestogens (overall mean, 41.1±11.9 μg/g) after hCG (75–150 IU, i.m.). Despite apparently normal ovarian responses, none of the females conceived after artificial insemination (AI). The gonadotropin‐induced nonpregnant luteal phase lasted 49.8±5.3 days (range, 30–60 days), whereas gestation lasted ～70 days. In the male Pallas' cat, fecal androgens were elevated from November–April (overall mean, 352.3±30.3 ng/g) compared with nadir concentrations during the rest of the year (82.1±3.3 ng/g). Entrainment of seasonality to photoperiod was demonstrated by stimulation of gonadal steroidogenic activity in cats exposed to increasing artificial light during natural (nonbreeding season) and artificially induced short‐day photoperiods. In summary, reproduction in Pallas' cats is highly seasonal and photoperiod‐dependent. Females exhibit elevated baseline and peak fecal estrogen concentrations for 3–4 months during late winter/early spring. Testicular steroidogenic activity precedes the rise in female estrogen excretion by about 2 months, presumably to ensure maximal sperm production during the breeding season. Zoo Biol 21:347–364, 2002. Published 2002 Wiley‐Liss, Inc.     

Carbonic anhydorase isoenzyme I (CA-I) concentration in feces and urine as a temporary marker of occult blood in beagle dogs.

This study was undertaken to investigate whether the concentration of carbonic anhydorase isoenzyme I (CA-I) in canine feces and urine is useful as a temporary marker of occult blood. Concentrations of CA-I were measured by enzyme-linked immunosorbent assay (ELISA). Fecal CA-I concentrations in 113 healthy beagle dogs (50 male and 63 female) of various ages ranged from 4.3 to 16.7 ng/g feces (mean; 7.0 +/- 2.9 ng/g feces). One milliliter of blood from 3 healthy beagle dogs was found to contain 1,047, 1,062 and 1,150 microg CA-I. The fecal CA-I concentrations of dogs receiving intragastric infusions of autologous blood (10 ml) were very low. However, the fecal CA-I concentrations of dogs receiving infusion of autologous blood (5 ml) into the ascending colon were very high. Detection of fecal CA-I would be useful for identifying dogs with hemorrhaging of the large intestine. Of 55 urinary samples collected from healthy beagle dogs by catheter, chemical tests for occult blood were negative in 44, but CA-I concentrations ranged from 1.8 to 12.6 ng/ml (mean; 6.9 +/- 5.4 ng/ml) by ELISA. The CA-I concentrations of the other 11 samples, which tested positive for occult blood on chemical testing, ranged from 41.2 to 525.0 ng/ml by ELISA. Although CA-I is not a specific marker of erythrocytes, CA-I may be used to detect occult blood in canine feces and urine until a specific immunological test kit using antibody for Hb is developed.     

Nonfaecal and faecal losses of the marine teleost, Lichia amia (Linnaeus, 1758), feeding on live southern mullet, Liza richardsonii (Smith, 1846)

1. Nonfaecal and faecal losses of Lichia amia were determined under controlled laboratory conditions at 15, 20 and 25 degrees C. 2. Ammonia-N was the major form of nonfaceal nitrogen excreted by L. amia and excretion rates were temperature-dependent. 3. The mass component b of the mass/ammonia-N excretion equation was temperature-independent and ranged from 0.63-0.65 and from 0.66-0.73 for starved and fed fish, respectively. 4. Mean nonfaecal energy loss (exogenous plus endogenous) was 3.78 +/- 1.99% of the ingested energy. 5. Assimilation efficiencies varied between individual fish and ranged from 61.24-93.79% (mean 80.76 +/- 7.14%) for dry matter and 87.52-98.22% (mean 94.09 +/- 2.22%) for energy. 6. The mean nonfaecal and faecal energy loss was 23.11 +/- 1.67% of the ingested energy.     

Digestibility, nitrogen excretion, and mean retention time by North American porcupines (Erethizon dorsatum) consuming natural forages

North American porcupines (Erethizon dorsatum) subsist predominantly on low-protein, high-fiber, high-tannin diets. Therefore, we measured the porcupine's ability to digest dry matter, fiber, and protein by conducting digestion trials on eight natural forages and one pelleted ration varying in concentration of fiber, nitrogen, and tannins. On these diets, dry matter intake ranged from 5 to 234 g/kg(0.75)/d and dry matter digestibility ranged from 62% to 96%. Porcupines digested highly lignified fiber better than many large hindgut fermenters and ruminants. The porcupine's ability to digest fiber may be explained, in part, by their lengthy mean retention time of particles (38.43+/-0.56 h). True nitrogen digestibility was 92% for nontannin forages and pellets. Endogenous urinary nitrogen was 205 mg N/kg(0.75)/d, and metabolic fecal nitrogen was 2.8 g N/kg dry matter intake. Porcupines achieved nitrogen balance at relatively low levels of nitrogen intake (346 mg N/kg(0.75)/d). Tannins reduced the porcupines' ability to digest protein. However, the reduction in protein digestion was not predictable from the amount of bovine serum albumin precipitated. Like many herbivores, porcupines may ameliorate the effects of certain tannins in natural forages on protein digestibility through physiological and behavioral adaptations.