Уточнить поиск
Результаты 41-50 из 90
Evaluation of use of progesterone to counteract zearalenone toxicosis during early pregnancy in gilts
1991
Green, M.L. | Stouffer, D.K. | Scheidt, A.B. | Long, G.G. | Diekman, M.A.
It has been shown that zearalenone disrupts early pregnancy in swine without altering intrauterine content of estradiol 17 beta or progesterone, embryo migration, or estradiol-17 beta thesis by blastocysts. However, serum concentrations of progesterone were reduced 2 to 3 weeks after mating in gilts that ingested zearalenone. Therefore, progesterone was administered to gilts during early pregnancy to determine whether it could counteract the detrimental actions of zearalenone on embryonic development. Thirty-two crossbred gilts (Hampshire X Chester White X Yorkshire X Duroc) were assigned randomly to a 2 X 2 factorial arrangement of treatments: zearalenone (Z); zearalenone plus progesterone (ZP); progesterone (P); or control (C). From postmating days 4 to 15, Z- and ZP-treated gilts were fed 1 mg of Z/kg of body weight, and P-treated and C gilts were fed ethanol as vehicle in a corn-soybean diet. On postmating days 3 to 15, P- and ZP-treated gilts were injected IM with 100 mg of progesterone, and C and Z-treated gilts were injected with progesterone carrier (15% ethanol, 15% benzyl alcohol, 70% propylene glycol). Blood was collected from gilts by puncture of the jugular vein daily from days 3 to 15, on alternate days from days 17 to 31, and then twice weekly until the end of the experiment. Fetal development was assessed in Z and ZP-treated gilts on postmating day 47.6 +/- 2.9 by cesarean section and in P-treated and c gilts at slaughter on postmating days 51.2 +/- 3.2. Serum concentrations of progesterone in P-treated gilts were greater on days 7 to 8, 10 to 15, 17, and 19 than in C gilts. Serum concentrations of progesterone were greater on days 8, 10, and 12 in ZP-treated than in C gilts. However, serum concentrations of progesterone were lower in ZP-treated gilts than in C gilts on postmating days 19 to 31. Serum concentrations of progesterone were lower in Z-treated gilts than C gilts on postmating days 15, 17, and 19. At slaughter or cesarean section, viable fetuses were not found in Z-treated gilts, but 80% of the C and P-treated gilts had viable fetuses. All Z-treated gilts were classified as pseudopregnant because uteri were turgid and the ovaries had functional corpora lutea. Uteri of ZP-treated gilts appeared normal. Corpora lutea of pregnancy had regressed by postmating day 35 in 7 of 8 ZP-treated gilts. Crown-to-rump length was similar between P-treated and C gilts (94 vs 92 mm). Fetal weight was similar between P-treated and C gilts (70 vs 62 g). These data demonstrate that 100 mg of progesterone/d failed to counteract the adverse effects of 1 mg of Z/kg of body weight on early pregnancy in primiparous gilts.
Показать больше [+] Меньше [-]Blastocyst development on days 10 or 14 after consumption of zearalenone by sows on days 7 to 10 after breeding
1989
Diekman, M.A. | Long, G.G.
Sixteen primiparous sows were bred and fed either a control ration (n = 8) or a diet containing purified zearalenone (n = 8; 1 mg/kg of body weight) from days 7 to 10 after breeding. On day 7 after breeding, the jugular vein of each sow was cannulated and blood was collected at 20-minute intervals for 4 hours before feeding and 4 hour after feeding. On day 10 after breeding, blood samples were collected from 4 control sows and 4 zearalenonefed sows at 20-minute intervals for 4 hours before collection of blastocysts. A similar blood sampling schedule was followed for the remaining 4 control and 4 zearalenone sows on day 14 after breeding. On day 10 after breeding, spherical blastocysts were recovered from all control sows and from 3 of 4 zearalenone-treated sows. Average diameter of blastocysts from zearalenone-treated sows were similar to that of control sows. On day 14 after breeding, blastocysts were recovered from all control sows and 3 of 4 zearalenone-treated sows. Blastocysts from the control sows were filamentous, whereas blastocysts from zearalenone-treated sows were fragmented and contained foci of necrosis. Incidence of luteinizing hormone (LH) secretory spikes per sow was less (P less than 0.01) in zearalenone-treated sows (0.25 +/- 0.25/4 h) than control sows (1.75 +/- 0.25/4 h) on day 10 after breeding. Incidence of follicle-stimulating hormone (FSH) secretory spikes was simillar (P = 0.45) among treatments on days 7, 10, and 14 after breeding. Mean serum concentrations of LH were less on day 10 (P = 0.07) and day 14 (P less than 0.01) in zearalenone-treated sows than in control sows (3.3 +/- 0.2 ng/ml vs 6.2 +/- 1.3). These data indicate that administration of zearalenone on days 7 to 10 after breeding altered secretory patterns of serum LH during days 10 and 14 after breeding, which may have contributed to the death of blastocysts by day 14 after breeding.
Показать больше [+] Меньше [-]Prevention of aflatoxicosis by addition of hydrated sodium calcium aluminosilicate to the diets of growing barrows
1989
Harvey, R.B. | Kubena, L.F. | Phillips, T.D. | Huff, W.E. | Corrier, D.E.
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 HSCA/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 less than 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 gamma-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 charaterized 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.
Показать больше [+] Меньше [-]Toxicologic evaluation of chlorpyrifos in cats
1988
Hooser, S.B. | Beasley, V.R. | Sundberg, J.P. | Harlin, K.
Twenty-four male domestic shorthair cats were used to evaluate the acute and chronic effects of a single, toxic but sublethal, orally administered dose of chlorpyrifos. A dose of 10 mg/kg of body weight did not induce clinical signs of toxicosis, but a dosage of 40 mg/kg induced clinical signs of toxicosis, and 1 of 12 cats died. Chlorpyrifos given at a dosage of 0.1 mg/kg to 2 cats reduced whole blood and plasma cholinesterase (Che) activities to values obtained after cats were given doses that induced clinical signs of toxicosis. Regeneration time for whole blood and plasma Che activities ranged from 7 to 28 days. Brain Che activity was considerably decreased in 1 cat that died 4.5 hours after dosing, but was normal in all others at 28 days after dosing. Other than decreased Che activity, significant changes were not seen in hematologic or serum biochemical values. Toxin-related lesions were not seen during macroscopic or microscopic examination.
Показать больше [+] Меньше [-]Anticoagulant Rodenticides in Nocturnal Birds of Prey: A European Perspective
2023
Andreia Garcês | Isabel Pires | Filipe Silva
Anticoagulant rodenticides are biocides that interfere with normal blood clotting, inhibit the vitamin K cycle in the liver, and cause death by hemorrhages. Even though the main target of these compounds is rodents, they may affect non-target species such as nocturnal birds of prey that feed on those rodents. To study secondary exposure to ARs, select species that specialize in rodent prey, such as nocturnal birds of prey. Besides their specialized diet in rodents, nocturnal birds of prey are one of the most widely distributed birds in Europe and live in rural and non-rural habitats, making them excellent sentinel species for several studies’ ecotoxicology studies. There are numerous studies regarding secondary AR exposure in raptor species all around the world, but evidence for population-level effects is still absent. The objective of this review is to show how ARs have influenced wild nocturnal birds of prey in Europe in the last decades, most affected species, and in summary, explain how they act and the main clinical signals/ lesions that can be observed in poisoned birds. Overall, a total of 19 works were included in this review, between the years 1983 to 2021 that satisfied all literature criteria. These 19 papers corresponded to 44 observations of different species, regarding eight types of anticoagulant rodenticide. In the future, more caution is needed in the use of anticoagulants for rodent control where avian predators may be exposed to poisoned prey. Some combinations can be highly lethal to the predator, putting it at risk species that are already treated, therefore new eco-friendly alternatives should be found.
Показать больше [+] Меньше [-]Pharmacokinetics of bupivacaine after intraperitoneal administration to cats undergoing ovariohysterectomy
2016
Benito Fernández, Javier | Monteiro, Beatriz P. | Beaudry, Francis | Lavoie, Anne-Marie | Lascelles, B. Duncan X. | Steagall, Paulo V.
OBJECTIVE To evaluate pharmacokinetics of bupivacaine after IP administration to cats undergoing ovariohysterectomy. ANIMALS 8 healthy cats. PROCEDURES Anesthesia was induced with propofol and maintained with isoflurane. Buprenorphine (0.02 mg/kg, IV) and meloxicam (0.2 mg/kg, SC) were administered. A 20-gauge catheter was inserted into a jugular vein for blood sample collection. A ventral midline incision was made, and a solution of 0.5% bupivacaine (2 mg/kg) diluted with an equal volume of saline (0.9% NaCl) solution (final concentration, 0.25% bupivacaine) was injected into the peritoneal space over the right and left ovarian pedicles and caudal aspect of the uterus before ovariohysterectomy. Cats were monitored for signs of bupivacaine toxicosis. Venous blood samples (2 mL) were collected before (time 0) and 2, 5, 10, 15, 20, 30, 60, 120, and 240 minutes after bupivacaine administration. Plasma bupivacaine concentrations were determined with a liquid chromatography–tandem mass spectrometry method. Pharmacokinetic parameters were determined by data plotting followed by analysis with a noncompartmental model. RESULTS No signs of bupivacaine toxicosis were observed. Maximum bupivacaine plasma concentration was 1,030 ± 497.5 ng/mL at a mean ± SD value of 30 ± 24 minutes after administration. Mean elimination half-life was 4.79 ± 2.7 hours. Mean clearance indexed by bioavailability and volume of distribution indexed by bioavailability were 0.35 ± 0.18 L•h/kg and 2.10 ± 0.84 L/kg, respectively. CONCLUSIONS AND CLINICAL RELEVANCE Intraperitoneal administration of bupivacaine resulted in concentrations that did not cause observable toxicosis. Studies to investigate analgesic effects for this technique in cats are warranted.
Показать больше [+] Меньше [-]Animal poisoning in Korea in 1974-June 2013
2013
Lee, H., Animal and Plant Quarantine Agency, Anyang, Republic of Korea | Bae, Y.C., Animal and Plant Quarantine Agency, Anyang, Republic of Korea | Lee, B., Animal and Plant Quarantine Agency, Anyang, Republic of Korea | Lee, K., Animal and Plant Quarantine Agency, Anyang, Republic of Korea | Baek, K., Animal and Plant Quarantine Agency, Anyang, Republic of Korea | Le,e M.H., Animal and Plant Quarantine Agency, Anyang, Republic of Korea
Animal poisoning has been occurred in Korea. However, the lack of the data about animal poisoning in Korea makes clinicians and diagnostician difficult to obtain information on poisoning cases. In this paper, we tried to gather information about animal poisoning from 1974 to June 2013 in Korea. Animal and Plant Quarantine Agency (QIA) record database were used to examine recent trends in animal poisoning. The analysis showed that the cattle was reported to be the most common species involved in animal poisoning and botulinum toxin constituted the primary group of toxicants. Animal poisoning occurred frequently on January and in Gyenggi-do. Although the data present in this manuscript is a little, it will be helpful to understand the general trend of animal poisoning in Korea.
Показать больше [+] Меньше [-]Toxicokinetics of norditerpenoid alkaloids from low larkspur (Delphinium andersonii) orally administered to cattle
2012
Green, Benedict T. | Welch, Kevin D. | Gardner, Dale R. | Stegelmeier, Bryan L. | Pfister, James A. | Cook, Daniel | Panter, Kip E.
Objective: To determine the toxicokinetics of N-(methylsuccinimido)anthranoyllycoctonine–type low larkspur alkaloids in beef cattle. Animals: 5 Black Angus steers and 35 Swiss Webster mice. Procedures: Low larkspur (Delphinium andersonii) was collected, dried, ground, and administered to 5 steers via oral gavage to provide a dose of 12 mg of N-(methylsuccinimido)-anthranoyllycoctonine alkaloids/kg. Steers were housed in metabolism crates for 96 hours following larkspur administration; heart rate was monitored continuously, and blood samples were collected periodically for analysis of serum concentrations of 16-deacetylgeyerline, methyllycaconitine, geyerline, and nudicauline and assessment of kinetic parameters. The LD50 of a total alkaloid extract from D andersonii was determined in Swiss Webster mice. Results: The alkaloids were quickly absorbed, with a maximum serum concentration achieved within 18 hours after administration. Geyerline and nudicauline coeluted as 1 peak and were considered together for toxicokinetic analysis. Mean ± SD elimination half-life was 18.4 ± 4.4 hours, 15.6 ± 1.5 hours, and 16.5 ± 5.1 hours for 16-deacetylgeyerline, methyllycaconitine, and geyerline and nudicauline, respectively. There were significant differences in maximum serum concentration, amount absorbed, and distribution half-life among the 4 alkaloids. The mouse LD50 was 9.8 mg/kg. Conclusions and Clinical Relevance: Results suggested that clinical poisoning was likely to be most severe approximately 18 hours after exposure. Cattle should be closely monitored for at least 36 hours after initial exposure. Additionally, a withdrawal time of approximately 7 days would be required to clear > 99% of the toxic alkaloids from the serum of cattle that have ingested low larkspur.
Показать больше [+] Меньше [-]Effects of intratumoral administration of a hyaluronan-cisplatin nanoconjugate to five dogs with soft tissue sarcomas
2012
Objective: To determine the effects of intratumoral injection of a hyaluronan-cisplatin nanoconjugate on local and systemic platinum concentrations and systemic toxicosis. Animals: 5 dogs with spontaneous soft tissue sarcomas (STSs). Procedures: For each dog, approximately 1.5 mL of hyaluronan nanocarrier conjugated with 20 mg of cisplatin was injected into an external STS. Blood samples were collected immediately before (0 hours) and at 0.5, 1, 2, 3, 4, 24, and 96 hours after hyaluronan-cisplatin injection for pharmacokinetic analyses. Urine samples were obtained at 0 and at 96 hours after hyaluronan-cisplatin injection for urinalysis. Each treated STS and its sentinel lymph nodes were surgically removed 96 hours after the hyaluronan-cisplatin injection. Inductively coupled plasma mass spectrometry was used to measure platinum concentrations in blood samples, tumors, and lymph nodes. Results: No tissue reactions were detected 96 hours after hyaluronan-cisplatin injection. Mean ± SD area under the curve, peak concentration, and terminal half-life for unbound (plasma) and total (serum) platinum were 774.6 ± 221.1 ng•h/mL and 3,562.1 ± 2,031.1 ng•h/mL, 56.5 ± 20.9 ng/mL and 81.6 ± 40.4 ng/mL, and 33.6 ± 16.1 hours and 51.2 ± 29.1 hours, respectively. Platinum concentrations ranged from 3,325 to 8,229 ng/g in STSs and 130 to 6,066 ng/g in STS-associated lymph nodes. Conclusions and Clinical Relevance: Intratumoral injection of the hyaluronan-cisplatin nanoconjugate was well tolerated in treated dogs. Following intratumoral hyaluronan-cisplatin injection, platinum concentration was 1,000-fold and 100-fold greater within treated tumors and tumor-draining lymphatics, respectively, compared with that in plasma.
Показать больше [+] Меньше [-]A case of treatment on amitraz toxicosis in a Thoroughbred racehorse
2010
Yang, J.H., Equine Hospital of Busan Race Park, Korea Racing Authority, Busan, Republic of Korea | Song, H.E., Equine Hospital of Busan Race Park, Korea Racing Authority, Busan, Republic of Korea | Lee, K.K., Jeju National University, Jeju, Republic of Korea | Jee, Y.H., Jeju National University, Jeju, Republic of Korea | Woo, H.C., Jeju National University, Jeju, Republic of Korea | Lim, Y.K., Jeju National University, Jeju, Republic of Korea
A 3-year-old female Thoroughbred racehorse was presented following the accidental oral and skin administration of amitraz. This case report describes the clinical signs and the treatment of this horse. Clinical signs of amitraz toxicosis are associated with the stimulation of alpha2-adrenergic receptors. Amitraz is seldom fatal because the effects can be reversed by alpha2-adrenergic antagonists. The horse displayed typical clinical signs of colic, including pawing, small hard drops, tranquillisation, depression, ataxia, muscular incoordination and impaction colic lasting up to 7 days. The syndrome was accompanied by mild dehydration. The horse survived after persistent symptomatic treatment, including the giving of intravenous fluids, antibiotics, multiple doses of mineral oil per os, nonsteroidal anti-inflammatory drugs and dexamethasone intramuscularly and intravenously.
Показать больше [+] Меньше [-]