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91.
Serum samples from 77 animals belonging to 38 species and 19 families in Rio de Janeiro Zoo, Brazil were tested for antibodies against serovars of Leptospira interrogans by microscopic agglutination test. Antibodies were detected in serum samples of 37.7% of all animals belonging to 10 families. Seropositivity was more common in the Carnivora Canidae (7/9), Procyonidae (5/9) and the Edentata Myrmecophagidae (5/9). Icterohaemorrhagiae was the most common serogroup. Seropositivity was less common in primates.  相似文献   
92.
    
This study assessed the efficiency of synchronous oestrous induction by light programme followed by two doses of cloprostenol in acyclic Saanen goats of different parity orders. Primiparous (n = 22) and multiparous (n = 33) goats were subjected to 16 hr of light and 8 hr of darkness for 60 days (D0-D60), starting 10 days after the winter solstice. All goats received 120 µg cloprostenol doses on D130 (morning) and D141.5 (afternoon) (11.5 days apart). Oestrus behaviour, ovarian follicular dynamics and serum progesterone (P4) analyses were recorded from D0 to D174 at different intervals. Animals in oestrus after D141.5 were randomly assigned into two groups: assisted natural mating (NM) or artificial insemination (AI; 10–24 hr after oestrus onset with frozen-thawed semen). From D57 to D120, 89.0% of goats presented large follicles (5–8 mm) and P4 concentrations were subluteal from D0 to D120. More multiparous compared to primiparous goats (54.5%, 18/33 vs. 18.2%, 4/22) exhibited oestrus after both injections. More primiparous compared to multiparous goats (54.5%, 12/22 vs. 12.1%, 4/33) did not exhibit oestrus after any injection. A total of 35 goats (64%) were in oestrus after the second prostaglandin injection and were subjected to NM or AI. The conception rate was similar among primiparous (70.0%, 7/10) and multiparous (68.0%, 17/25) goats but the pregnancy rate differed, being 31.8% (7/22) and 51.5% (17/33), respectively. No interaction was found between parity order and P4 concentrations in does that became pregnant or not. Thus, the association between light programme (60 days, starting at the beginning of winter) and two cloprostenol administrations 11.5 days apart (starting 70 days after the end of the light treatment) resulted in sufficient synchronous oestrous response in multiparous acyclic Saanen goats to reach satisfactory fertility levels after both NM and AI.  相似文献   
93.
Tropical Animal Health and Production - This study evaluated the effect of energy and protein supplementation on the nutritional characteristics, ingestive behavior, and productive performance in...  相似文献   
94.
The iron-reducing activity of coffee beverages was determined by the ferric reducing antioxidant power (FRAP) assay. The influence on FRAP due to the degree of roasting (light, medium, and dark), species (Coffea arabica and Coffea robusta), and caffeine content (regular and decaffeinated) was investigated using ground and soluble coffee samples. The concentration of specific chlorogenic acids and caffeine in the beverages was determined by high-performance liquid chromatography and related to FRAP using Pearson correlation coefficients. All measurements were expressed per unit of soluble solids. Beverages prepared with ground coffee had, on average, 27% higher FRAP values than those prepared with soluble coffee (p < 0.05). In the former beverages, FRAP of C. robusta samples was significantly higher (on average, 50.3%) when compared to that of C. arabica samples, and FRAP values decreased with increasing degree of roasting (p < 0.05). A strong correlation (r > 0.91) was found between FRAP and the total content of chlorogenic acids, particularly that of the caffeoylquinic acid isomers. The iron-reducing activity of coffee beverages was not influenced by caffeine.  相似文献   
95.
    
Nitrogen (N) and potassium (K) fertilization play a key role in forage crops and can significantly increase yields of ‘Marandu’ palisadegrass [Brachiaria brizantha (Hochst. exA. Rich.) Stapf.], one of the most important forage crops in Brazil. This study aimed to identify the concentrations of total N and K, nitrate (NO3?), and ammonium (NH4+), chlorophyll meter readings (SPAD), and nitrate reductase activity (At-RNA) required to maximize yield. Plants were grown in quartz substrate and treated with nutrient solutions that ranged from 2 to 33 mmol L?1 for N and 0.5 to 11 mmol L?1 for K. Dry matter production and At-RNA increased with increasing N and K supplies. SPAD readings correlated strongly with N leaf concentration and dry matter production and can be used to assess the N status of this species. The supply of N and K in the fertilization promoted high yield and adequate N and K concentration for plant metabolism.  相似文献   
96.
    
Soil sulfur (S) partitioning among the various pools and changes in tropical pasture ecosystems remain poorly understood. Our study aimed to investigate the dynamics and distribution of soil S fractions in an 8‐year‐old signal grass (Brachiaria decumbens Stapf.) pasture fertilized with nitrogen (N) and S. A factorial combination of two N rates (0 and 600 kg N ha–1 y–1, as NH4NO3) and two S rates (0 and 60 kg S ha–1 y–1, as gypsum) were applied to signal grass pastures during 2 y. Cattle grazing was controlled during the experimental period. Organic S was the major S pool found in the tropical pasture soil, and represented 97% to 99% of total S content. Among the organic S fractions, residual S was the most abundant (42% to 67% of total S), followed by ester‐bonded S (19% to 42%), and C‐bonded S (11% to 19%). Plant‐available inorganic SO4‐S concentrations were very low, even for the treatments receiving S fertilizers. Low inorganic SO4‐S stocks suggest that S losses may play a major role in S dynamics of sandy tropical soils. Nitrogen and S additions affected forage yield, S plant uptake, and organic S fractions in the soil. Among the various soil fractions, residual S showed the greatest changes in response to N and S fertilization. Soil organic S increased in plots fertilized with S following the residual S fraction increment (16.6% to 34.8%). Soils cultivated without N and S fertilization showed a decrease in all soil organic S fractions.  相似文献   
97.
    
ObjectiveTo compare the effects of tramadol alone, or in combination with dipyrone or meloxicam, on postoperative pain and analgesia requirement after unilateral mastectomy with or without ovariohysterectomy in dogs.Study designProspective, randomized, clinical study.AnimalsTwenty seven bitches undergoing unilateral mastectomy with or without ovariohysterectomy.MethodsAnesthesia was induced with propofol and maintained with isoflurane and a constant rate infusion of morphine. Before the end of surgery, dogs were randomly assigned to receive intravenous tramadol alone (3 mg kg?1, group T), combined with dipyrone (30 mg kg?1, group TD) or meloxicam (0.2 mg kg?1, group TM). Dogs received additional doses of tramadol (groups T and TM) or tramadol with dipyrone (group TD) at 8 and 16 hours after extubation. Postoperative pain was assessed by a blinded observer before anesthesia (baseline) and at 1, 2, 3, 4, 6, 8, 12, 16 and 24 hours after extubation using a visual analog scale (VAS) and a modified Glasgow scale. Rescue analgesia (morphine, 0.5 mg kg?1) was administered if the Glasgow pain score was >3.5.ResultsThere were no significant differences among groups in pain scores evaluated by the VAS or the Glasgow scale. In groups T, TD and TM, pain scores were significantly higher than at baseline for 6, 8 and 2 hours, respectively. Rescue analgesia was administered to 3/9, 2/9 and 1/9 dogs in groups T, TD and TM, respectively (p > 0.05) [Correction added on 15 August 2013, after first online publication: ‘T, TM and TD’ was changed to ‘T, TD and TM’.].Conclusions and clinical relevanceUnder the conditions of this study, tramadol alone or in combination with dypyrone or meloxicam provided effective analgesia for 24 hours in most dogs after unilateral mastectomy with or without ovariohysterectomy. Further evaluation of combination therapies is needed in larger groups of dogs.  相似文献   
98.
  总被引:1,自引:0,他引:1  
OBJECTIVE: To evaluate the effects of acepromazine maleate on the cardiovascular changes induced by dopamine in isoflurane-anesthetized dogs. STUDY DESIGN: Prospective, randomized cross-over experimental design. ANIMALS: Six healthy adult spayed female dogs weighing 16.4 +/- 3.5 kg (mean +/- SD). METHODS: Each dog received two treatments, at least 1 week apart. Acepromazine (0.03 mg kg(-1), IV) was administered 15 minutes before anesthesia was induced with propofol (7 mg kg(-1), IV) and maintained with isoflurane (1.8% end-tidal). Acepromazine was not administered in the control treatment. Baseline cardiopulmonary parameters were measured 90 minutes after induction. Thereafter, dopamine was administered intravenously at 5, 10, and 15 microg kg(-1) minute(-1), with each infusion rate lasting 30 minutes. Cardiopulmonary data were obtained at the end of each infusion rate. RESULTS: Dopamine induced dose-related increases in cardiac index (CI), stroke index, arterial blood pressure, mean pulmonary arterial pressure, oxygen delivery index (DO(2)I) and oxygen consumption index. In the control treatment, systemic vascular resistance index (SVRI) decreased during administration of 5 and 10 microg kg(-1) minute(-1) of dopamine and returned to baseline with the highest dose (15 microg kg (-1) minute(-1)). After acepromazine treatment, SVRI decreased from baseline during dopamine administration, regardless of the infusion rate, and this resulted in a smaller increase in blood pressure at 15 microg kg (-1) minute(-1). During dopamine infusion hemoglobin concentrations were lower following acepromazine and this contributed to significantly lower arterial O(2) content. CONCLUSIONS: Acepromazine prevented the return in SVRI to baseline and reduced the magnitude of the increase in arterial pressure induced by higher doses of dopamine. However, reduced SRVI associated with lower doses of dopamine and the ability of dopamine to increase CI and DO(2)I were not modified by acepromazine premedication. CLINICAL RELEVANCE: Previous acepromazine administration reduces the efficacy of dopamine as a vasopressor agent in isoflurane anesthetized dogs. Other beneficial effects of dopamine such as increased CO are not modified by acepromazine.  相似文献   
99.
An incompetent vulvar seal leads to reproductive failure, and a surgical intervention might be required. The present paper describes modifications to Pouret's surgery. We suggest the use of a simple interrupted vertical mattress suture, which avoids seroma. Eighteen Brazilian Jumping Horse mares, older than 20 years and barren for 3-5 consecutive years, underwent modified Pouret's surgery. A horizontal skin incision of 3-4 cm was made half way between the anus and upper commissure of the vulva. The submucosal and connective tissue were dissected, and the rectovaginal shelf was split horizontally by sectioning the muscular and ligamentous connections between the anus, vulva, caudal portion of the rectum, and vagina until the vulva was oriented vertically. The wound was changed from a horizontal plane to a vertical plane by placing the suture vertically using approximately eight interrupted U sutures distributed in two layers with polyamide thread. The modified Pouret's surgical technique provided a perfect coaptation of the vulvar lips and a correct perineal position. Those mares that presented with horizontally tipped vulvar lips due to advanced age and stretching of the pelvic tissues by multiple foaling had their vulvas replaced. Also, the surgical procedure was easy to perform. As to fertility, of the 18 initial mares, 14 were inseminated, and all became pregnant. Thus, it was possible to conclude that the anatomical changes performed throughout the surgical procedure predisposed to a better vulvar coaptation, correcting the pneumovagina.  相似文献   
100.
    
ObjectiveTo evaluate the effects of methadone, administered alone or in combination with acepromazine or xylazine, on sedation and on physiologic values in dogs.Study designRandomized cross-over design.AnimalsSix adult healthy mixed-breed dogs weighing 13.5 ± 4.9 kg.MethodsDogs were injected intramuscularly with physiologic saline (Control), or methadone (0.5mg kg−1) or acepromazine (0.1 mg kg−1) or xylazine (1.0 mg kg−1), or acepromazine (0.05 mg kg−1) plus methadone (0.5 mg kg−1) or xylazine (0.5 mg kg−1) plus methadone (0.5 mg kg−1) in a randomized cross-over design, with at least 1-week intervals. Sedation, pulse rate, indirect systolic arterial pressure, respiratory rate (RR), body temperature and pedal withdrawal reflex were evaluated before and at 15-minute intervals for 90 minutes after treatment.ResultsSedation was greater in dogs receiving xylazine alone, xylazine plus methadone and acepromazine plus methadone. Peak sedative effect occurred within 30 minutes of treatment administration. Pulse rate was lower in dogs that received xylazine either alone or with methadone during most of the study. Systolic arterial pressure decreased only in dogs receiving acepromazine alone. When methadone was administered alone, RR was higher than in other treatments during most of the study and a high prevalence of panting was observed. In all treatments body temperature decreased, this effect being more pronounced in dogs receiving methadone alone or in combination with acepromazine. Pedal withdrawal reflex was absent in four dogs receiving methadone plus xylazine but not in any dog in the remaining treatments.Conclusions and clinical relevanceMethadone alone produces mild sedation and a high prevalence of panting. Greater sedation was achieved when methadone was used in combination with acepromazine or xylazine. The combination xylazine–methadone appears to result in better analgesia than xylazine administered alone. Both combinations of methadone/sedative were considered effective for premedication in dogs.  相似文献   
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