bluuebunny/crossref_metadata_2025 huggingface dataset:
The nature of embryo reduction in mares with twin conceptuses: Deprivation hypothesis
Authors: Ginther O. J.
Published: February 2025

Ultrasonography was used to determine whether there is embryo reduction in mares with unilaterally fixed twins when a major portion of the vascularized area of the wall of one of the embryonic vesicles is in apposition with the wall of the adjacent vesicle, rather than with the endometrium (deprivation hypothesis). In addition, the effect of ovulatory pattern (synchronous and asynchronous) on the incidence of embryo reduction was studied. Twin vesicles were ultrasonically detected on days 11 to 15 (ovulation = day 0) and were examined daily until there was embryo reduction or until day 40. In 31 mares with twin embryonic vesicles, unilateral fixation (71 %) was more frequent (P < 0.05) than was bilateral fixation (29%). In 28 mares with known ovulatory patterns, synchronous ovulations did not affect the type of fixation (9/17 unilateral and 8/17 bilateral); however, for asynchronous ovulators the frequency of unilateral fixation (10/11) was greater (P < 0.01) than the frequency of bilateral fixation (1/11). The incidence of embryo reduction was greater (P < 0.01) for unilateral fixation (14/19) than for bilateral fixation (0/9) and was greater (P < 0.05) for asynchronous ovulators (9/11) than for synchronous ovulators (5/17).

In mares with embryo reduction, the reduction was complete before detection of both embryo propers (early reduction) in 10/14 and after detection both embryo propers (late reduction) in 4/14. For 17 synchronous ovulators, fewer underwent early embryo reduction (0 mares) than late reduction (5 mares) or no reduction(12 mares; 4 unilateral and 8 bilateral), whereas in the 11 asynchronous ovulators, more underwent early reduction (8 mares) than late reduction (1 mare) or no reduction (2 mares; 1 unilateral and 1 bilateral; P < 0.01).

In mares with early embryo reduction, the orientation and spatial relationship of one vesicle relative to the other was not determinable until the embryo proper was detected. In the 2 mares in which the embryo proper of the survivor was detected before embryo reduction was complete, the embryo proper was located opposite to the site of reduction, ie, the vesicle that was to be eliminated impinged on the thin-walled area of the yolk sac wall of the survivor. The position of the embryo proper and its emerging allantoic sac seemed to determine whether a given conceptus survived or underwent late embryo reduction. The embryo proper, the vascularized wall of the yolk sac adjacent to the embryo proper, and the emerging allantoic sac were exposed to the endometrium (uterine lumen) in the surviving vesicles; in the vesicles that underwent reduction, much of the corresponding area of the vesicle wall was covered by the wall of the adjacent survivor. The results supported the deprivation hypothesis.
Hemostasis development in the lamb fetus and neonate
Authors: Moalic Pascale , Gruel Yves , Foloppe Patrick , Delahousse Bénédicte , Leclerc Marie-Hélène , Leroy Jean
Published: February 2025

Fetal and neonatal lamb hemostasis were studied from the 60th day of pregnancy to birth. Platelet counts and blood coagulation, as assessed by tests such as recalcification time and thromboelastography, were similar in fetuses, neonates, and adult sheep. The values of coagulation factors were low, ie, vitamin K-dependent Factors II, VII, IX, and X remained unchanged (30 and 40% of adult reference values) until the last 10 days of gestation, and then increased until birth (40 to 60%). Values of fibrinogen and Factor V followed a similar pattern, although their activities became identical to adult values at birth. Also, we measured values of protein C and antithrombin III, which are synthesized by the liver. The importance of hepatic failure and fetal vitamin K deficiency were discussed. Factors VIII and XII activities increased gradually during pregnancy to reach adult values at birth. Fetal fibrinolytic activity increased. This could not be explained by the values of tissue-type plasminogen activator (it was not detectable) or by the presence of its fast acting inhibitor, whose concentration did not decrease.
Concentration of receptors for estradiol and progesterone in canine endometrium during estrus and diestrus
Authors: Fernandes P. A. , Bowen R. A. , Sawyer H. R. , Nett T. M. , Gorell T. A.
Published: February 2025

Receptors for estrogen and progesterone were measured in cytosols prepared from specimens of canine endometrium obtained at late proestrus, day 4 of estrus, day 2 of diestrus, and at 10 day intervals from days 10 through 80 of diestrus. Twenty nine adult bitches were used, with 2 to 4 dogs used at each time point. Concentrations of estradiol receptors measured in endometrial cytosols from late proestrus through day 10 of diestrus were similar (mean ± SEM : 9.9 ± 2.2, 10.5 ± 1.2, 16.3 ± 1.6, and 16.2 ± 2.9 pmol/g of tissue at proestrus, day 4 of estrus, days 2 and 10 of diestrus, respectively). As serum concentrations of progesterone increased during early diestrus, the concentration of estradiol receptors decreased and were significantly (P < 0.05) lower on days 30 (4.9 ± 1.3 pmol/g of tissue) and 40 (3.7 ± 0.6 pmol/g of tissue) of diestrus. After day 40 of diestrus, when serum concentrations of progesterone were approaching basal concentration, the concentration of estradiol receptors increased and remained significantly (P < 0.05) higher from days 60 to 80 of diestrus (day 60, 13.4 ± 2.9; day 70, 15.7 ± 1.7; day 80, 19.8 ± 2.4 pmol/g of tissue). As observed for estrogen receptors, the concentration of endometrial receptors for progesterone also gradually increased from late proestrus (4.9 ± 1.3 pmol/g of tissue) to day 2 of diestrus (6.4 ± 0.3 pmol/g of tissue). When serum concentrations of progesterone increased during early diestrus, the concentration of progesterone receptors significantly (P < 0.05) decreased after day 2 of diestrus and remained low until day 40 of diestrus (day 10, 1.7 ± 0.1; day 20, 2.3 ± 0.2; day 30, 1.2 ± 0.2; day 40, 1.5 ± 0.1 pmol /g of tissue). Thereafter, when serum concentrations of progesterone returned to basal concentrations, the concentration of progesterone receptors significantly (P < 0.05) increased and remained constant from days 50 to 80 of diestrus (day 50, 4.6 ± 0.9; day 60, 6.6 ± 0.3; day 70, 6.7 ± 0.7; day 80, 5.5 ± 0.4 pmol /g of tissue).
Bioassay techniques and high-performance liquid chromatography for detection of oxytetracycline residues in tissues from calves
Authors: MacNeil James D. , Korsrud Gary O. , Naylor Jonathan M. , Yates William D. G.
Published: February 2025

Tissue specimens from muscle, liver, kidney, and injection sites were collected, and serum was obtained from 3 calves euthanatized on each of posttreatment days 5 and 22. Calves were treated with 6.7, 13.4, or 20 mg of oxytetracycline (otc)/kg of body weight, im, once daily for 3 days; these dosages are 1, 2, and 3 times the label dose, respectively. One control calf was euthanatized on each of posttreatment days 5 and 22.

In treated male calves killed 2 days after the last injection, otc residues were detected in all tissues and serum, using high-performance liquid chromatography. Tissues from all injection sites also were considered positive for antimicrobial residues, using the swab test on premises (stop), microbial inhibition test (mit), and thin-layer chromatography-bioautography (tlcb) test. Kidney tissues from a calf given 13.4 mg of otc/kg and kidney and liver tissues from a calf given 20 mg of otc/kg also were considered positive, using the mit and tlcb. Results of the stop only were considered positive for the liver and kidney of a calf given 20 mg of otc/kg, but substitution of Saskatoon antibiotic medium-3 for the original medium (antibiotic medium-5) allowed the stop to detect residues in these tissues from all treated calves.

In female calves killed 19 days after the last injection, the stop, mit, and tlcb procedures revealed positive results for tissues from some injection sites, but revealed negative results for other tissues. High-performance liquid chromatographic analyses detected otc in tissues from injection sites from all treated calves, in muscle and liver from a calf given 20 mg of otc/kg, and in kidneys from calves given 13.4 or 20 mg of otc/kg.

The stop, mit, and tlcb procedures lacked the sensitivity of high-performance liquid chromatography for detection of otc residues. However, the stop procedure with Saskatoon antibiotic medium-3 did perform appropriately in that it failed to detect label doses in tissues from injection sites, but did detect 2 and 3 times extralabel doses after the recommended withdrawal time, and results were considered positive for all tissues after 2 days of withdrawal. A significant (P < 0.05) loss of otc was not observed after samples were stored at −20 C for 80 days. The highest concentration of otc residues persisted in kidneys and tissues from injection sites.
Immunohistochemical evaluation of intermediate filament expression in canine and feline neoplasms
Authors: Moore A. S. , Madewell B. R. , Lund J. K.
Published: February 2025

Specimens of neoplastic tissues from 19 dogs and 4 cats were examined immunohistochemically for intermediate filament expression, using commercially available antibodies. Staining was observed in a wide range of tumor tissues and in normal internal controls by use of antibodies to vimentin, desmin, glial fibrillary acidic protein, and low and high molecular weight cytokeratins. Intermediate filament expression was found to be consistent with light and/or electron microscopic findings, and hence believed to be an accurate indicator of tumor histogenesis in cats and dogs. Three fixatives were evaluated for their relative abilities to preserve antigenicity. Absolute alcohol was superior to B5 fixative and both were superior to formalin. Some tissues that clearly displayed intermediate filament antigens with alcohol and B5 fixative failed to stain when fixed in formalin.
Relationship of serum ferritin and iron concentrations and serum total iron-binding capacity to nonheme iron stores in dogs
Authors: Weeks Bradley R. , Smith Joseph E. , Northrop Janis K.
Published: February 2025

The relationships of various iron-related analytes were evaluated in 95 dogs. Liver and spleen nonheme iron content was determined coulometrically on acid-digested tissue specimens. Serum iron concentration and total iron-binding capacity also were measured coulometrically, whereas serum ferritin concentration was measured by ELISA. Significant (P < 0.0002) correlation was found between serum ferritin concentration and nonheme iron stores. Significant correlation was not found. between nonheme iron stores and serum iron concentration or total iron-binding capacity. Serum ferritin concentration should provide a convenient and relatively noninvasive means of estimating iron stores in dogs.
Expression of von Willebrand factor in plasma and platelets of cats
Authors: Waters Diane C. , Eaton Anthony H. , Steidley Kevin R. , McCarroll David R.
Published: February 2025

Immunochemical methods that are used to assess von Willebrand factor in human beings and dogs were used to assess von Willebrand factor in 3 cat species. Our findings indicated that the expression and multimeric composition of von Willebrand factor in plasma and platelets of cats were similar to those reported in human beings and dogs. We suggest that these methods may be used to evaluate von Willebrand disease in members of the cat family used in this study.
Prevalence estimation from pooled samples
Authors: Sacks Jerome M. , Bolin Steven R. , Crowder Stephen V.
Published: February 2025

Under certain conditions, prevalence can be estimated by testing samples from individual members or by pooling samples from members into a group and by testing the sample from the group as a single unit. Pooled tests are more accurate than individual tests when P is < 10%. Optimal group size is 1.6/P. Efficiency decreases slowly with suboptimal size and rapidly with overly large size.
Alterations in bovine lymphocyte function during the periparturient period
Authors: Kehrli Marcus E. , Nonnecke Brian J. , Roth James A.
Published: February 2025

Lymphocytes from 8 Holstein heifers were evaluated during the periparturient period for mitogen-induced lymphocyte blastogenic responses. Phytohemagglutinin P- and concanavalin A-induced lymphocyte blastogenesis increased 2 and 3 weeks before parturition, respectively. However, by the first week after parturition, lymphocyte blastogenesis was markedly impaired.
Effects of 4% pilocarpine gel on normotensive and glaucomatous canine eyes
Authors: Carrier Michel , Gum Glenwood G.
Published: February 2025

A 4% pilocarpine gel applied topically to eyes was evaluated in glaucomatous Beagles and normotensive Miniature Schnauzers to determine its efficacy in reducing intraocular pressure (IOP) and to assess any side effects. Pilocarpine gel significantly (P < 0.05) reduced IOP for 24 hours after treatment, compared with baseline (predrug) values, untreated fellow eyes, and placebo-treated eyes. The IOP remained significantly lower (P < 0.05) during 3 treatment days, as well as the first 2 days after treatment. The pupil sizes were significantly smaller (P < 0.01) in all treated dogs after the first administration of pilocarpine, compared with baseline values, untreated eyes, and placebo-treated eyes. The subsequent pilocarpine gel administrations induced significant miosis (P < 0.01), compared with baseline values, but the extent of miosis and duration were significantly less (P < 0.01) as the number of treatments increased. Conjunctival irritation and blepharospasm were observed mainly in the first 2 days of treatment and were minimal after subsequent applications. There was no contralateral effect on IOP or pupil size, compared with baseline values and placebo-treated eyes.
Effects of ketamine, xylazine, and a combination of ketamine and xylazine in Pekin ducks
Authors: Ludders J. W. , Rode J. , Mitchell G. S. , Nordheim E. V.
Published: February 2025

Effects of ketamine, xylazine, and a combination of ketamine and xylazine were studied in 12 male Pekin ducks (7 to 12 weeks old; mean [± SD] body weight, 3.1 ± 0.3 kg). After venous and arterial catheterization and fixation of a temperature probe in the cloaca, each awake duck was confined, but not restrained, in an open box in a dimly lit room. Blood pressure and lead-II ECG were recorded. Three arterial blood samples were collected every 15 minutes over a 45-minute period (control period) and were analyzed for pHa, PaCO2 and PaO2. After the control period, each duck was assigned at random to 1 of 3 drug groups: (1) ketamine (KET; 20 mg/kg of body weight, IV), (2) xylazine (XYL; 1 mg/kg, IV), and (3) KET+XYL (KET 20 mg/kg and XYL, 1 mg/kg; IV). Measurements were made at 1, 5, 10, 15, 30, 45, 60, and 90 minutes after drug administration.

All ducks survived the drug study. Cloacal temperature was significantly (P ≤ 0.05) increased above control cloacal temperature at 90 minutes after the administration of ketamine, and from 10 through 90 minutes after administration of ketamine plus xylazine. In ducks of the KET group, pHa, PaCO2, and PaO2, remained unchanged after administration of the drug. In ducks of the XYL group, pHa and PaO2 decreased significantly (P ≤ 0.05) from control values for all time points up to and including 15 minutes after drug administration. In ducks of the KET + XYL group, pHa and PaO2 were significantly (P ≤ 0.05) decreased at all time points up to and including 45 and 15 minutes, respectively, after administration of the drugs. In ducks of the XYL group, PaCO2 increased significantly (P ≤ 0.05) during the first 15 minutes after drug administration, and for 45 minutes after administration of KET + XYL. Results indicated that ketamine when given alone to ducks, was not associated with pulmonary depression. There was drug-associated respiratory depression after IV administration of XYL or KET + XYL.
Duration of experimentally induced Corynebacterium bovis colonization of bovine mammary glands during the lactating, nonlactating, and peripartum periods
Authors: Sordillo L. M. , Oliver S. P. , Doane R. M. , Shull E. P. , Maki J. L.
Published: February 2025

Bovine mammary glands were inoculated intracisternally with a streptomycin-resistant (SR) strain of Corynebacterium bovis to determine the number of colonyforming units (CFU) required to induce colonization and to maintain persistence of C bovis colonization throughout lactation and involution. Streptomycin resistance was used as a strain marker. Uninfected quarters in cows during midlactation were challenge exposed with successively higher numbers of SR C bovis until all quarters became colonized. Inoculum containing 790 CFU of SR C bovis established colonization in only 7 of 38 quarters. Colonization persisted in only 4 of these quarters by 23 days after inoculation. Eleven quarters were reinoculated with higher numbers of SR C bovis, and all became colonized by the time challenge-exposure inoculum contained 8 × 104 CFU. Colonization persisted throughout the 93- day experimental period. Somatic cell counts were sig-nificantly (P < 0.01) higher in SR C bovis-colonized quarters after inoculation than before. Sixteen additional quarters were inoculated with a mean number of 8 × 104 CFU of SR C bovis 7 days before suppression of lactation. All quarters became colonized, and SR C bovis was shed during the experimental period; throughout the nonlactating and peripartum periods, high numbers of SR C bovis in pure culture were shed from 13 of 16 quarters.
Effect of water vapor-saturated air therapy on bronchoalveolar lavage and tracheal mucus transport rate in clinically normal horses
Authors: Sweeney Corinne Raphel , Leary Herbert J. , Ziemer Ellen L. , Spencer Pamela A.
Published: February 2025

Water vapor-saturated air was delivered to 12 healthy, housed horses for 2 hours daily for 5 days. Treatment had no effect on tracheal mucus transport rate, bronchoalveolar lavage total and differential cell counts, blood cell counts, or plasma fibrinogen concentration.
Fatal Pasteurella haemolytica pneumonia in bighorn sheep after direct contact with clinically normal domestic sheep
Authors: Foreyt William J.
Published: February 2025

Six Rocky Mountain bighorn sheep were raised in captivity from birth (n = 5) or taken from the wild as a lamb (n = 1). After the bighorn sheep were in captivity for over a year, 6 clinically normal domestic sheep were placed on the 2 ha of pasture on which the bighorn sheep were kept. Nasal swab specimens were obtained from all sheep at the time the domestic sheep were introduced. Pasteurella haemolytica was isolated from swab specimens obtained from 4 of 6 domestic sheep, but not from specimens obtained from the bighorn sheep. All 6 bighorn sheep died of acute hemorrhagic pneumonia after exposure to domestic sheep. Death in the bighorn sheep occurred on days 4, 27, 27, 29, 36, or 71 after initial exposure to domestic sheep. Pasteurella haemolytica was isolated from respiratory tract tissue specimens of all bighorn sheep at the time of death. None of the domestic sheep were clinically ill during the study. At the end of the study, 3 of 6 domestic sheep were euthanatized, and at necropsy, P haemolytica was isolated from 2 of them. The most common serotypes in bighorn and domestic sheep were P haemolytica T-3 and A-2. Other serotypes isolated included P haemolytica A-1, A-9, and A-11 in bighorn sheep and A-1 in domestic sheep.

On the basis of results of this study and of other reports, domestic sheep and bighorn sheep should not be managed in proximity to each other because of the potential fatal consequences in bighorn sheep.
Role of IgE in the pathogenesis of bovine respiratory syncytial virus in sequential infections in vaccinated and nonvaccinated calves
Authors: Stewart Robert S. , Gershwin Laurel J.
Published: February 2025

A study was undertaken to evaluate the possible role of IgE in the pathogenesis of bovine respiratory syncytial virus (brsv) infection. Fifteen calves were allotted at random to 3 treatment groups. One group of 6 calves was vaccinated with attenuated brsv vaccine before live-virus challenge exposure, another group of 6 was not vaccinated before challenge exposure, and the remaining 3 calves served as controls (nonvaccinated, nonchallenge exposed). Calves of the 2 experimental groups were exposed to 2 live-virus aerosolizations (challenge exposure) 35 days apart. Histamine and brsv-specific IgE (brsv-IgE) concentrations in serum, lung lavage fluid, and nasopharyngeal exudate, as well as clinical signs of disease, were evaluated for 14 days after each challenge exposure. Vaccination before challenge exposure with live brsv appeared to have little or no effect on the severity of the disease, but did appear to affect disease persistence. A correlation (P < 0.02) existed between signs of disease and brsv-IgE concentration measured in lung lavage fluid, but this was only true for vaccinated calves. Although no other correlations were found between clinical signs of disease and IgE concentration, analysis of the results additionally revealed a strong correlation (P < 0.002) between disease signs and histamine concentration in nasopharyngeal exudate from calves of both experimental groups. Thus, indirect evidence implicated IgE in brsv infection pathogenesis.
Complement, bacteriostatic, and enzymatic activities in sera from guinea pigs given aflatoxin and/or rubratoxin
Authors: Thurston John R. , Sacks Jerome M. , Richard John L. , Peden W. Michael , Driftmier Kim
Published: February 2025

The relationship of serum complement activity and bacteriostatic activity was investigated in male guinea pigs given aflatoxin and/or rubratoxin. In experiment 1, guinea pigs were given 0.6 mg of aflatoxin/kg of body weight, po, once. In experiment 2, guinea pigs were given 0.02 mg of aflatoxin/kg, po, and/or 8 mg of rubratoxin, po, 11 times. Aflatoxin (0.02 mg/kg) had no effect given alone, but potentiated the effect of rubratoxin. In both experiments, changes in complement activity were accompanied by similar but not always significant (P < 0.05) changes in bacteriostatic activity of serum. Guinea pigs given 0.06 mg of aflatoxin/kg had significant (P < 0.05) changes in complement titers and in serum alkaline phosphatase, alanine aminotransferase, and aspartate aminotransferase activities. Guinea pigs given repeated oral doses of aflatoxin and/or rubratoxin had changes in complement titers, bacteriostasis, and alkaline phosphatase and aspartate aminotransferase activities, but not in alanine aminotransferase activities. Significant differences were detected only when average values for all guinea pigs given rubratoxin or rubratoxin with aflatoxin were compared with average values for guinea pigs not given rubratoxin.
Myoelectric activity of the cecum and right ventral colon in female ponies
Authors: Ross Michael W. , Rutkowski Judith A. , Cullen Kenneth K.
Published: February 2025

The myoelectric activity of the cecum and right ventral colon (rvc) was studied in 4 female ponies. Eight, bipolar Ag-AgCl electrodes were sequentially placed on the seromuscular layer of the cecum (6 electrodes) and rvc (2 electrodes), and recordings were begun 14 days after surgery. The myoelectric activity for each pony was recorded during 12, 60-minute recording sessions done during the interdigestive period (3 to 7 hours after the morning feeding).

Coordinated series of spike bursts were recognized as independent motility patterns in the cecum and in the rvc. Local haustra-haustra myoelectric activity involving approximately 40 cm of the cecal body (0.45 ± 0.03 spike bursts/min) were detected. A series of spike bursts started at the cecal apex and progressed to, but stopped at, the caudal cecal base (0.40 ± 0.03 spike bursts/min). Infrequently, a series of spike bursts started at the apex and progressed to the cranial cecal base (0.09 ± 0.01 spike bursts/min). More commonly, a series of spike bursts with a conduction velocity of 3.8 ± 0.07 cm/s, began in the cranial base and progressed orally to the cecal apex (0.46 ± 0.03 spike bursts/min). Spike bursts conducted aborally (propulsion) beginning at the origin of the rvc (0.05 ± 0.007 spike bursts/min) and spike bursts conducted orally (retropulsion; 0.15 ± 0.02 spike bursts/min) were seen independent of cecal myoelectric activity.

A progressive series of coordinated spike bursts, which began at the cecal apex, were conducted through the cecolic orifice and continued into the rvc (0.42 ± 0.02 spike bursts/min), representing the only pattern common to the cecum and rvc. This pattern, associated with a loud rush of ingesta heard on auscultation, had a conduction velocity of 5.65 ± 0.12 cm/s and was always generated in the cecal body, near the apex. An apparent electrical pacemaker area was proposed in this area. Duration of spiking activity during the progressive pattern was significantly (P = 0.0001) greater at electrodes 7 and 8 in the rvc than at any electrode locus in the cecum. Coordinated orally directed spike bursts were detected frequently in the cecum before and after the progressive pattern, indicating a complex sequence of motility patterns may exist.
Hemolytic anemia and red blood cell metabolic disorder attributable to low phosphorus intake in cows
Authors: Ogawa Eri , Kobayashi Kosaku , Yoshiura Nobuyuki , Mukai Jun
Published: February 2025

Hypophosphatemia was induced in 2 cows by reducing phosphorus content in their feed after parturition. Serum inorganic phosphorus (Pi) values decreased to 1 mg/dl within 10 days after parturition; and rbc adenosine 5’- triphosphate (atp) and reduced glutathione values decreased to 50 and 70% of baseline values, respectively. Methemoglobin concentration was moderately higher than normal. These changes preceded the onset of hemolysis, and anemia progressed with decreases in pcv, hemoglobin concentration, and rbc counts. Serum Pi resumed its normal value when anemia was most severe. This rbc disorder was confirmed to be characteristic of hemolytic anemia in cows resulting from hypophosphatemia. The rbc glycolytic intermediates, total triose phosphate (combined glyceraldehyde-3-phosphate and dihydroxyacetone phosphate content) and fructose-1,6-diphosphate, greatly increased in vivo and in vitro with decreases in serum or plasma Pi and rbc atp. From our results, we concluded that inadequate Pi in the plasma impairs the function and viability of rbc by hindering the production of atp via disturbance of reactions at the glyceraldehyde-3-phosphate dehydrogenase step.
Prevention of aflatoxicosis by addition of hydrated sodium calcium aluminosilicate to the diets of growing barrows
Authors: Harvey Roger B. , Kubena Leon F. , Phillips Timothy D. , Huff William E. , Cornier Donald E.
Published: February 2025

Hydrated sodium calcium aluminosilicate (hscas), an anticaking agent for mixed feed, was added to the diets of growing barrows and was evaluated for its potential to ameliorate the clinical signs of aflatoxicosis. The experimental design consisted of 6 treatments of 5 barrows each at concentrations of 0 g of hscas and 0 g of aflatoxin (af)/kg of feed (control), 5 g of hscas/kg of feed (0.5%), 20 g of hscas/kg of feed (2.0%), 3 mg of af/kg of feed, 5 g of hscas (0.5%) plus 3 mg of af/kg of feed, or 20 g of hscas (2.0%) plus 3 mg of af/kg of feed. Barrows were maintained in indoor concrete-floored pens, with feed and water available ad libitum for 28 days (from the age of 7 to 11 weeks). Barrows were observed twice daily and were weighed weekly, and blood samples were obtained weekly for hematologic and serum biochemical measurements. At the termination of the study, barrows were euthanatized and necropsied. Body weight gains were diminished significantly (P < 0.05) by consumption of 3 mg of af/kg of feed, whereas body weight gain in barrows consuming diets containing hscas or hscas plus af did not differ from that in control barrows. Serum enzymatic activities of alkaline phosphatase and γ-glutamyl transferase and prothrombin time were increased in barrows consuming 3 mg of af/kg of feed, but not in those consuming hscas or hscas plus af. Aflatoxin alone induced decreased serum concentrations of urea nitrogen, albumin, total protein, calcium, phosphorus, cholesterol, and glucose, as well as serum total iron-binding capacity, whereas hscas or hscas plus af did not induce such effects. Liver weight was increased in barrows of the af-alone treatment group, compared with control barrows. Hepatic lesions in barrows of the af-alone treatment group were characterized as peripheral lobular lipidosis accompanied by periportal and interlobular fibrosis and bile duct hyperplasia. Hepatic lesions were not observed in barrows of the 0.5% hscas plus af or 2.0% hscas plus af treatment groups. These findings suggested that hscas can modulate the toxicity of af in growing barrows (perhaps via sequestration and reduced bioavailability in vivo) and may offer a novel approach to the preventive management of aflatoxicosis in animals.
Efficacy of triclabendazole against experimentally induced Fascioloides magna infections in sheep
Authors: Foreyt William J.
Published: February 2025

Efficacy of oral administration of 20 mg of triclabendazole/kg of body weight was evaluated against 12-week Fascioloides magna infections in 12 sheep, each inoculated orally with 250 viable metacercariae. From 6 sheep treated with triclabendazole, 1 immature F magna was recovered, whereas 116 F magna with a mean length of 19 ± 6.5 mm were recovered from 6 untreated control sheep. Efficacy of triclabendazole was 99.14%. Signs of toxicosis or illness were not observed in the sheep.
Gastric emptying of a radionuclide-labeled test meal after surgical correction of gastric dilatation-volvulus in dogs
Authors: van Sluijs F. J. , van den Brom W. E.
Published: February 2025

Gastric emptying of a radionuclide-labeled test meal was studied in 10 dogs that had been treated surgically i for gastric dilatation-volvulus and in 10 clinically normal (control) dogs. There were no significant differences between the gastric emptying rates and patterns in treated and in control dogs. Thus, there are no indications that gastric emptying is delayed in dogs that have recovered from gastric dilatation-volvulus, and there is no reason for pyloric surgery in dogs with this condition.
Colostral volume and immunoglobulin G and M determinations in mares
Authors: Lavoie Jean-Pierre , Spensley Michael S. , Smith Bradford P. , Mihalyi Judy
Published: February 2025

Colostral volume and IgG and IgM concentrations were determined in 6 multiparous mares at foaling and then every 2 hours from 16 to 20 hours after parturition. Serum IgG and IgM concentrations at foaling also were determined in each mare. The rate of mammary secretion was 292 ± 26 ml/h (range, 202 to 389 ml/h), and the colostral volume was 5.1 ± 0.5 L (range, 3.2 to 7.0 L). The colostral IgG and IgM contents were 440 ± 106 g (range, 199 to 855 g) and 3.1 ± 0.9 g (range, 0.7 g to 7.1 g), respectively. There was no significant correlation between serum and initial colostral IgG and IgM concentration or between serum and total colostral IgG or IgM values. The colostral IgG and IgM concentrations at foaling correlated well with the total colostral IgG and IgM contents, respectively. The initial 250 ml of colostrum contained 10 ± 1.4% (range, 6.0 to 13.9%) and 6 ± 1.0% (range, 2.4 to 8.5%) of the total IgG and IgM contents, respectively, and the initial 500 ml of colostrum contained 20 ± 2.7% (range 12.0 to 27.1%) and 14 ± 1.2% (8.2 to 17%) of the total colostral IgG and IgM contents, respectively.
Natural killer cell activity in untreated and treated dogs with lymphoma
Authors: Raskin Rose E. , Tvedten Harold W. , Bull Robert W. , Crow Steven E. , Dunstan Robert W. , Krehbiel Janver D.
Published: February 2025

Natural killer (nk) cell activity and function were determined for 11 untreated and treated dogs with lymphoma. Concurrent chromium release and single cell binding assays, methods used to measure overall cytotoxic activity and that from individual cells, respectively, were performed at effector-to-target cell ratios of 50:1 and 100:1, with incubation periods of 12 and 16 hours. Significant reduction was achieved in overall activity for untreated dogs, using a 16-hour incubation period and an effector-to-target ratio of 100:1 (P < 0.05). Decreased activity (P < 0.025) was also achieved for those dogs that were administered combination chemotherapy, consisting of such drugs as cyclophosphamide, vincristine, prednisone, and doxorubicin. There was no significant difference in binding or cytotoxic activity by individual cells in the untreated or treated dogs, compared with the healthy controls. Short- or long-term treatment with glucocorticoids did not influence overall nk cell activity or individual cell cytotoxicity. The overall cytotoxic activity in untreated dogs was reduced, but these dogs had relatively normal numbers of nk cells compared with paracontrols. This suggests that a defect in recycling, or the ability to kill targets repetitively, may be involved. A similar defect was found in nk cells of dogs treated aggressively with combination chemotherapy.
In vitro immune monitoring of antibody response in dogs given chemoimmunotherapy for lymphoma
Authors: Jeglum K. Ann , Winters Wendell D. , Young Karen M.
Published: February 2025

Clinical remission in 30 dogs with lymphoma was induced with a combination of vincristine, l-asparaginase, cyclophosphamide, and doxorubicin HCl, administered sequentially, and then an autochthonous tumor cell vaccine, given intralymphatically, as maintenance therapy. Humoral antibody amounts were monitored in 11 dogs, using a solid-phase bead-type radioimmunoassay. The median survival of the 30 dogs was 13 months from the start of chemotherapy (range, 7 to 25 months; mean, 13.8). The median remission duration was 16 weeks (range, 9 to 98 weeks; mean, 26.8). Correlation between increase in amount of humoral antibody was significant (P = 0.0001 to 0.012), before and after chemoimmunotherapy, in dogs responding to therapy, compared with that in dogs not responding to therapy.
Pharmacokinetics of single-dose administration of moxalactam in unweaned calves
Authors: Soback Stefan
Published: February 2025

Twenty-nine healthy 17- to 29-day-old unweaned Israeli-Friesian male calves were each given a single iv or im injection of 10 or 20 mg of moxalactam disodium/kg of body weight. Serum concentrations were measured serially during a 12-hour period. Serum concentration vs time profiles were analyzed by use of linear least-squares regression analysis and the statistical moment theory. The elimination half-lives after IV administration were 143.7 ± 30.2 minutes and 155.5 ± 10.5 minutes (harmonic mean ± sd) at dosages of 10 and 20 mg of moxalactam/kg of body weight, respectively. Corresponding mean residence time values were 153.1 ± 26.8 minutes and 169.9 ± 19.3 minutes (arithmetic mean ± sd). Mean residence time values after im administration were 200.4 ± 17.5 minutes and 198.4 ± 19.9 minutes at dosages of 10 and 20 mg/kg, respectively. The volumes of distribution at steady state were 0.285 ± 0.073 L/kg and 0.313 ± 0.020 L/kg and total body clearance values were 1.96 ± 0.69 ml/min/kg and 1.86 ± 0.18 ml/min/kg after administration of dosages of 10 and 20 mg/kg, respectively. Moxalactam was rapidly absorbed from the im injection site and peak serum concentrations occurred at 1 hour. The estimated bioavailability ranged from 69.8 to 79.1%. The amount of serum protein binding was 53.4, 55.0, and 61.5% when a concentration of moxalactam was at 50, 10, and 2 μg/ml, respectively. The minimal inhibitory concentrations of moxalactam ranged from 0.01 to 0.2 μg/ml against Salmonella and Escherichia coli strains and from 0.005 to 6.25 μg/ml against Pasteurella multocida strains.
Pharmacokinetics of oxytetracycline in the turkey: Evaluation of biliary and urinary excretion
Authors: Dyer D. C.
Published: February 2025

Oxytetracycline (otc) pharmacokinetic values in plasma and bile were ascertained after IV administration of the drug. At 6 hours after administration of 1 mg of otc/kg of body weight, 2.15% of the dose was found in the bile and 37.6% was found in the urine. At 2 hours after administration, the peak bile-to-plasma otc concentration ratio was 60:1. Bioavailability of otc was 47.6% when it was administered orally to fasted turkeys and was 9.4% when administered to fed turkeys.
Modified in vitro method to label equine red blood cells with technetium 99m in concentrated whole blood
Authors: Koblik Philip D. , Hornof William J. , Srivastava Suresh C.
Published: February 2025

An in vitro method to label equine rbc with technetium 99m was modified to achieve quantitative labeling of cells in concentrated whole blood. After a blood sample was incubated with a reducing agent (stannous citrate), an oxidizing reagent (NaOCl) and a chelating agent (edta) were added to inactivate residual Sn2+ in the plasma. This step prevented premature reduction of pertechnetate in plasma. Labeling of rbc from 9 healthy horses, using a standard whole blood protocol, resulted in only moderate labeling efficiency (44 to 85%) and indicated a linear relationship between labeling efficiency and pcv. Effects of increased incubation time, increased incubation temperature, prelabeling sedimentation, and double addition of NaOCl/edta were investigated in whole blood from 10 healthy horses. Labeling efficiency was improved by each independent factor and by combination of factors. Highest labeling efficiencies (96 to 97%) were achieved when blood samples were sedimented for 20 minutes before being labeled, regardless of incubation time or incubation temperature. Morphologic features of rbc were unaffected by labeling procedures.

In vivo whole blood clearance time for labeled cells was determined in 5 healthy horses. Sedimented blood samples were labeled, using a standard 15-minute incubation time at 20 to 22 C. Mean clearance half-time for 5 horses was approximately 20 hours. More than 95% of 99mTc activity was associated with the cells during the 24 hours after reinjection.
Infertility in heifers inoculated with modified-live bovine herpesvirus-1 vaccinal strains against infectious bovine rhinotracheitis on postbreeding day 14
Authors: Miller J. M. , Van Der Maaten M. J. , Whetstone C. A.
Published: February 2025

Heifers were inoculated iv with 1 of 4 modified-live bovine herpesvirus-1 vaccinal strains against infectious bovine rhinotracheitis (2 heifers/strain) on postbreeding day (pbd) 14. The effect of infection on fertility was monitored by plasma progesterone assay at 1- to 3-day intervals from the time of virus exposure until pbd 60. Infertility was detected in 4 of 8 inoculated heifers. In 2 heifers, progesterone concentrations decreased to values indicative of estrus within 10 days after inoculation (pbd 24). The 2 other heifers had evidence of embryonic death on pbd 40 and 42. Two control heifers inoculated with culture medium from noninfected cells maintained their pregnancies.
Effect of Pasteurella haemolytica (A1) capsular polysaccharide on sheep lung in vivo and on pulmonary surfactant in vitro
Authors: Brogden Kim A. , Adlam C. , Lehmkuhl Howard D. , Cutlip Randall C. , Knights J. M. , Engen Richard L.
Published: February 2025

Capsular polysaccharide (CP) of Pasteurella haemolytica (type A1) was first deposited by fiberoptic bronchoscopy into the lungs of sheep to examine lesions and changes in bronchoalveolar lavage cell populations and, later, was mixed with pulmonary surfactant to investigate alterations in physical properties or surface tension. At 22 hours after deposition, minimal lesions were seen in the lungs only at and contiguous to the site of cp deposition in 2 of 4 sheep. Microscopically, alveoli and interlobular septa were filled with edema fluid. Terminal airways and alveoli contained a moderate amount of neutrophils that varied between sheep. Significant differences in number or type of bronchoalveolar lavage cells were not observed in the weekly lavages between each group or among sheep within each group, either before or after deposition of cp or physiologic saline solution.

After 6 hours of incubation at 37 C, cp-surfactant mixtures were examined with a surface tensiometer and centrifuged in sucrose gradients. The cp bound to surfactant, resulting in formation of a precipitate with a surface tension of 31.6 ± 0.1 dynes/cm and a density of 1.07 to 1.08 g/ml. Lipopolysaccharide of P haemolytica, used as a control, also bound to surfactant, resulting in a complex with a surface tension of 57.7 ± 0.4 dynes/cm and a density of 1.06 to 1.10 g/ml. Surfactant alone had a surface tension of 32.6 ± 0.2 dynes/cm and density of 1.05 to 1.06 g/ml. The cp appears by itself not to be a direct major factor in the lung damage that develops in cases of pneumonic pas-teurellosis. However, the precipitation of surfactant by cp may be a lectin reaction that would allow the attachment of the organism to the lining of the alveolus and become established during an infection.
Efficacy of long-acting oxytetracycline alone or in combination with streptomycin for treatment of Brucella ovis infection of rams
Authors: Marín Clara M. , de Bagués María P. Jiménez , Barberán Montserrat , Blasco José M.
Published: February 2025

Twenty-four rams inoculated with Brucella ovis by conjunctival and preputial routes were treated with a long-acting oxytetracycline alone or in combination with di-hydrostreptomycin sulfate. The combined treatment eliminated Brucella ovis from 11 of 12 (91.6%) treated rams. Only 4 of 12 (33.3%) rams treated with oxytetracycline alone were bacteriologically negative. Neither treatment resolved clinical epididymitis in 2 rams affected before treatment. Many rams had pathologic lesions in the epididymis and ampullae, which limited the efficacy of antibiotic treatment.
Distribution of bovine cysticercosis in Washington
Authors: Hancock Dale D. , Wikse Steven E. , Lichtenwalner Anne B. , Wescott Richard B. , Gay Clive C.
Published: February 2025

Data from slaughter plants (n = 3) and feedlots (n = 18) in eastern Washington were analyzed to characterize occurrence patterns of cysticercosis in Washington during 1984. Three concurrent peaks in cysticercosis rates (0.6/1,000 to 5/1,000 slaughtered cattle) were detected at 3 slaughter plants. Peaks were observed at 8 feedlots from December 1983 to March 1984, at 6 feedlots from April to July 1984, at 2 feedlots from August to October 1984, and at 3 feedlots from November 1984 to February 1985. Affected feedlots were not closely associated geographically and were feeding cattle from many, predominantly northwestern, origins. For 3 feedlots for which time in the feedlot was available for each slaughter shipment, an increase in cysticercosis rate with increasing time in the feedlot was noticed. Within these 3 feedlots, cases of cysticercosis were widely scattered spatially. The pattern of cysticercosis indicated human fecal contamination of a regionally available feed source. Of feedstuffs in use, potato waste, a byproduct of the processed potato industry, appeared to be the most likely source of Taenia saginata ova.
Hematologic, biochemical, blood-gas, and acid-base values in Greyhounds before and after exercise
Authors: Ilkiw Jan E. , Davis Philip E. , Church David B.
Published: February 2025

After racing 722 m, 16 Greyhounds were evaluated to determine changes in hematologic, biochemical, blood-gas, and acid-base values following exercise. Values were determined before racing (T0), immediately after racing (T1), and 3 hours after racing (T2). Significant changes detected immediately after racing included increased heart rate, respiratory rate, and rectal temperature. Significant changes in hematologic values included increases in pcv, total plasma protein, hemoglobin, rbc, wbc, neutrophils, and lymphocytes. Change was not detected in values for monocytes, eosinophils, and neutrophil/lymphoçyte ratio. Other increases included those for plasma concentrations of sodium, chloride, calcium, lactic acid, aspartate transaminase, alanine transaminase, alkaline phosphatase, creatine kinase, lactate dehydrogenase, and glucose. Concentrations of potassium and urea did not change. Measurement of blood-gas and acid-base status revealed significant increases in Pao2 and base deficit, whereas Paco2, pH, and bicarbonate decreased. Three hours after exercise, all vital signs and blood-gas and acid-base values, except for Paco2, which was still slightly low, had returned to baseline (T0) values. Most biochemical values had also returned to baseline, although sodium, chloride, aspartate transaminase, and creatine kinase were still high, and urea was low. Many hematologic values were still different from baseline values, with high values for wbc, neutrophils and neutrophil/lymphocyte ratio, and low values for pcv, total plasma protein, hemoglobin, rbc, and lymphocytes.
Cell proliferation of epidermis, hair follicles, and sebaceous glands of Beagles and Cocker Spaniels with healthy skin
Authors: Kwochka Kenneth W. , Rademakers Adriana M.
Published: February 2025

Cell proliferation kinetic values were established for the epidermis, hair follicle epithelium, and sebaceous glands of 10 Beagles and 4 Cocker Spaniels with healthy skin and coats. Values were established by intradermal pulse-labeling injections of [3H]thymidine, examination of cutaneous biopsied tissues, and autoradiography. The epidermal basal cell-labeling index was 1.41 ± 0.46% for Beagles and 1.71 ± 0.56% for Cocker Spaniels. The hair follicle basal cell-labeling index was 1.46 ± 0.78 and 1.07 ± 0.42%, respectively. Calculated epidermal cell-renewal time for viable layers of the epidermis was 23.38 ± 5.93 days for Beagles and 20.97 ± 4.92 days for Cocker Spaniels. Differences between cell kinetic data for the 2 breeds were not significant (P > 0.05).

The basal cell-labeling index for the sebaceous gland was significantly (P = 0.009) lower for Cocker Spaniels (0.40 ± 0.18%) than for Beagles (1.81 ± 1.08%). Seemingly, epidermal and follicular cell proliferation kinetics in healthy dogs was similar between the 2 breeds, whereas sebaceous gland basal cells were less proliferative in healthy Cocker Spaniels than in healthy Beagles.
Pathogenesis of psoroptic scabies in Hereford heifer calves
Authors: Stromberg Paul C. , Guillot Frank S.
Published: February 2025

Hereford heifer calves were experimentally infested with Psoroptes ovis. Histologic examination of skin specimens was conducted at weekly intervals before and after treatment with ivermectin on postinfestation week 7. Electron microscopy revealed numerous degranulating mast cells in the skin of infested but not in control calves. Many active, as well as degenerate, neutrophils were in the scab on infested calves. Microscopic epidermal ulcers developed on infested calves when live mites were present but not after treatment. Numbers of dermal neutrophils and plasma cells decreased and numbers of circulating neutrophils increased 1 week after treatment. Numbers of dermal eosinophils and mast cells in calves with eosino-philia increased for several weeks after treatment. Statistical analysis indicated significant correlations (P < 0.05) among numbers of dermal inflammatory cells, hem-ogram values, and changes in dermal thickness. Seemingly, mite-induced epidermal damage was the key pathogenic event in psoroptic scabies in calves. Mast cell degranulation contributed to the pathogenesis of the dermatitis, and neutropenia was caused by sustained, poorly compensated efflux of neutrophils into the scab through mite-induced breaks in the epidermis.