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121.
Breeding efforts have been undertaken to increase resistance of maize to fusarium ear rot (FER) and to fumonisin accumulation. Flavonoids in the pericarp of the kernels are considered particularly able to reduce the fumonisin accumulation. The aim of this 2‐year field study was to assess the effect of flavonoids on FER symptoms and fumonisin contamination in maize kernels using two isogenic hybrids, one providing pigmentation in the pericarp (P1‐rr) and the other without it (P1‐wr). FER incidence (FERi), FER severity (FERs), the incidence of infections caused by Fusarium spp. in symptomless kernels (FF) and fumonisin contamination (FUM) were assessed in both hybrids. Significant differences between the two hybrids were detected mainly in 2012 trials where P1‐rr showed lower FERi (< 0·01), FF (< 0·05) and FUM (< 0·1) than P1‐wr. Site, characterized by local temperature and precipitation, played a relevant role in modelling all the measured variables, as its effect was highly significant in both years, whether they were considered individually or altogether. The interaction of hybrid with location was a significant (< 0·001) source of variation only for FF. FF, together with FERi, was also significantly (< 0·001) influenced by the interaction of hybrid with year. In general, FUM was more influenced by year and location parameters, such as temperatures during late ripening, than by flavonoid presence in kernel pericarp. The results indicate that flavonoid pigments alone may not be an important component in the resistance of maize to fumonisin accumulation.  相似文献   
122.
This study investigated the effects of different concentrations of FSH (10, 50, 100 and 200 ng/ml) in supplemented MEM+ on the development of equine pre‐antral follicles that were cultured in vitro for 2 or 6 days. The ovaries (n = 5) from mares in seasonal anoestrus were collected from a local abattoir. Ten ovarian tissue fragments of approximately 3 × 3 × 1 mm were obtained from each animal. The fragments were cultured in situ for 2 days (D2) or 6 days (D6) in MEM+ or MEM+ supplemented with FSH at four different concentrations, establishing the following 11 groups: control (D0); MEM + (D2); MEM + (D6); MEM + 10 ng/ml of FSH (D2); MEM + 10 ng/ml of FSH (D6); MEM + 50 ng/ml of FSH (D2); MEM + 50 ng/ml of FSH (D6); MEM + 100 ng/ml of FSH (D2); MEM + 100 ng/ml of FSH (D6); MEM + 200 ng/ml of FSH (D2); and MEM + 200 ng/ml of FSH (D6). Follicles were observed in only 9.65% (388 of 4,018) of the histological sections. Of the 861 follicles evaluated, 488 were in the primordial stage, and 373 were in various developmental stages; 59.7% were morphologically normal. Regarding the integrity of the pre‐antral follicles, the groups with 100 ng/ml FSH of 2‐days culture as well as 50, 100 and 200 ng/ml FSH of 6‐days culture provided the best results. In conclusion, the in vitro culture of abattoir‐derived equine ovarian fragments presented better morphological integrity when supplemented with FSH for 6 days, in comparison with the MEM culture group. However, no clear effects were observed with FSH regarding the promotion of activation from a primordial to a developing follicle.  相似文献   
123.

Objective

Influence of detomidine or romifidine constant rate infusion (CRI) on plasma lactate concentration and isoflurane requirements in horses undergoing elective surgery.

Study design

Prospective, randomised, blinded, clinical trial.

Animals

A total of 24 adult healthy horses.

Methods

All horses were administered intramuscular acepromazine (0.02 mg kg?1) and either intravenous detomidine (0.02 mg kg?1) (group D), romifidine (0.08 mg kg?1) (group R) or xylazine (1.0 mg kg?1) (group C) prior to anaesthesia. Group D was administered detomidine CRI (10 μg kg?1 hour?1) in lactated Ringer's solution (LRS), group R romifidine CRI (40 μg kg?1 hour?1) in LRS and group C an equivalent amount of LRS intraoperatively. Anaesthesia was induced with ketamine and diazepam and maintained with isoflurane in oxygen. Plasma lactate samples were taken prior to anaesthesia (baseline), intraoperatively (three samples at 30 minute intervals) and in recovery (at 10 minutes, once standing and 3 hours after end of anaesthesia). End-tidal isoflurane percentage (Fe′Iso) was analysed by allocating values into three periods: Prep (15 minutes after the start anaesthesia–start surgery); Surgery 1 (start surgery–30 minutes later); and Surgery 2 (end Surgery 1–end anaesthesia). A linear mixed model was used to analyse the data. A value of p < 0.05 was considered significant.

Results

There was a difference in plasma lactate between ‘baseline’ and ‘once standing’ in all three groups (p < 0.01); values did not differ significantly between groups. In groups D and R, Fe′Iso decreased significantly by 18% (to 1.03%) and by 15% (to 1.07%), respectively, during Surgery 2 compared with group C (1.26%); p < 0.006, p < 0.02, respectively.

Conclusions and clinical relevance

Intraoperative detomidine or romifidine CRI in horses did not result in a clinically significant increase in plasma lactate compared with control group. Detomidine and romifidine infusions decreased isoflurane requirements during surgery.  相似文献   
124.

This study evaluated the influences of nitrogen fertilizer and energy supplementation cattle on the growth performance of beef cattle. This study was conducted at the Federal University of Technology of Paraná, Dois Vizinhos through continuous grazing on 6.3 ha, divided into nine paddocks. The treatments were: Alexander grass +100 kg ha?1 of N (N100); Alexander grass + 100 kg ha?1 of N + 0.5 kg per 100 kg of weight live supplementation of wheat bran (N100S); and Alexander grass +200 kg ha?1 of N (N200), with an average herbage allowance of 10% for all treatments. Crossbred and non-castrated steers with an average weight of 276 ± 41 kg were used for 107 days. The crude protein from entire plant differed (P < 0.05) between treatments, with the greater value (14.8%) occurring in the N200, and the lesser value (13.3%) occurring in the N100S. The herbage accumulation rate was greater (P < 0.05) in the N200 (55.7  DM ha?1 d?1) than that in the N100S and N100 (40.0 and 39.7 kg DM ha?1 d?1, respectively). The N100S produced greater (P < 0.05) average daily weight gains (0.815 kg animal day?1) than did the N200 (0.685 kg animal day?1) and N100 treatments (0.727 kg animal day?1).

  相似文献   
125.
Toxoplasma gondii is an apicomplexan protozoan parasite which is able to infect a large variety of warm-blooded animals. Raw or undercooked pork has been regarded as an important source of infection for humans. The aim of this study was to evaluate an in-house enzyme-linked immunosorbent assay to diagnose natural T. gondii infection in swine using native affinity chromatography-purified T. gondii surface protein-1 (TgSAG1-ELISA) as antigen, comparing its performance to that of indirect fluorescent antibody test (IFAT) and immunoblotting (IB). To obtain a panel of sera showing the evolution of the antibody response in the time course 12 pigs were experimentally inoculated intravenously (iv) with tachyzoites of the T. gondii strains RH (clonal type I), ME49 (clonal type II) and NED (clonal type III) and serologically monitored for a period of 11 weeks. Both IFAT and ELISA showed a similar time course of antibody response to T. gondii; but by IFAT this response was characterized by rapidly rising titers with peaks at two weeks post inoculation (wpi), while the ELISA indices increased slowly and reached a maximum in most animals at five wpi. Three-hundred randomly selected sera from a total of 602 pigs of different ages derived from outdoor and indoor farms from Argentina were analyzed. Serum samples testing either positive or negative by both IFAT and IB were considered as "relative standards of comparison" (RSC). Sensitivity and specificity of TgSAG1-ELISA were obtained by a Receiver Operating Characteristics (ROC) analysis and statistical agreement among serological tests was evaluated. Antibodies to T. gondii were detected in 160 of 300 sera (53.3%) by IB, in 133 of 300 (44.3%) by IFAT and in 123 of 300 sera (41%) by TgSAG1-ELISA. One hundred and eleven sera tested positive and 118 sera tested negative by both IFAT and IB (RSC); 103 of 111 positive RSC sera tested positive by TgSAG1-ELISA, and 116 of 118 negative RSC sera tested negative by TgSAG1-ELISA. Agreement observed between RSC and TgSAG1-ELISA was almost perfect (κ=0.9124, p≥0.05) and between IFAT and IB was moderate (κ=0.53, p≥0.05). Relative sensitivity and specificity of the TgSAG1-ELISA using a cut-off index of 0.204 were of 92.8% and 98.3%, respectively. ROC analysis revealed that TgSAG1-ELISA was highly accurate (AUC=0.983) relative to the RSC. According to the results in this study, the ELISA based on affinity purified T. gondii surface antigen TgSAG1 was useful for the specific and sensitive detection of antibodies to this protozoan parasite in naturally infected pigs.  相似文献   
126.
127.
128.
Llamas (Lama glama) are South American camelids described as intermediate hosts of Neospora caninum, Toxoplasma gondii and Sarcocystis aucheniae. Due to the potential role of these protozoan infections as a cause of economic losses, the aim of this study was to determine the seroprevalence for T. gondii, N. caninum and Sarcocystis sp. in llamas from Argentina. Serum samples from 308 llamas (>2 years old) were collected between 2005 and 2007. A total of 55 farms located in six departments of Jujuy province, Argentina were sampled. Presence of antibodies to N. caninum, T. gondii and Sarcocystis sp. was determined by the indirect fluorescent antibody test (IFAT). For Sarcocystis, 2 different bradyzoites-based antigens were prepared using S. aucheniae and S. cruzi. Sera were tested at dilutions 1:25 and 1:50. Antibodies to N. caninum were found in 4.6% serum samples. Fifty percent of departments and 14.5% of farms had positive animals. Antibodies to T. gondii were found in 30% of samples, distributed in 66% of departments and 43.6% of farms. Antibodies to Sarcocystis sp. were detected in 96% of samples and all departments and farms had positive animals, suggesting frequent contact between llamas and canids. Co-infection with N. caninum, T. gondii and Sarcocystis sp. was also recorded. Low seroprevalence of N. caninum in llamas detected in this study could be related to climatic and geographical conditions that limit cattle breeding activity, reducing the source of infection for definitive hosts. Seroprevalence of T. gondii and the positive animal distribution suggest frequent contamination of grass with felid faeces. In conclusion, this is the first report of combined seroprevalence for N. caninum, T. gondii and Sarcocystis sp. in llamas. Further studies are needed to determine the potential role of these protozoan infections as cause of abortion in Argentina as well as presence of these protozoans in llama meat used for human consumption.  相似文献   
129.
AIM: To investigate the attitudes of veterinary practitioners in New Zealand to pain and analgesia, and their use of analgesic drugs, in dogs and cats.

METHODS: A questionnaire posted to 1,200 practising veterinarians was used to gather information about the use of analgesia in dogs and cats, assessment of pain, attitudes to pain relief, analgesic drugs and procedures used, factors affecting choice of analgesic agent, and veterinary demographics, continuing education and staffing.

RESULTS: Three hundred and twenty questionnaires with useable data were returned, a response rate of 28%. Male and female veterinarians were evenly represented. The analgesic agents most commonly used were morphine (opioids) and carprofen (a non-steroidal anti-inflammatory drug; NSAID). Use of peri-operative pain relief ranged from 50% for castration of cats to 91% for fracture repair in dogs. For most procedures, female veterinarians scored pain at a significantly higher level than their male colleagues. Fifty-eight percent of respondents considered their knowledge in the area of assessment and treatment of pain was adequate.

CONCLUSIONS: This survey was considered representative of veterinarians working in companion animal practice in New Zealand. Results indicated a relatively high use of peri-operative analgesia, including both pre-emptive and multi-modal analge- sia, in cats and dogs, although there was still some disparity between the perception of how painful a procedure was and the consequent use of pain relief.

CLINICAL RELEVANCE: The establishment of current attitudes and practices indicates to practising veterinarians how their own use of analgesics compares with that of their colleagues. It also provides information to educators on potential areas of focus, given that 42% of respondents felt their knowledge in the area of assessment and treatment of pain was inadequate.  相似文献   
130.
Water buffalo industry has become a profitable activity worldwide, including the Northeast of Argentina (NEA). However, research on diseases affecting this species is scarce. The aim of the present study was to detect antibodies against Brucella abortus, Leptospira spp., Neospora caninum, Toxoplasma gondii, and Sarcocystis spp. in 500 water buffalo cows from five ranches (100 animals each) in the NEA. Serum samples were tested for B. abortus by fluorescence polarization assay, Leptospira spp. by microagglutination test, and N. caninum, T. gondii, and Sarcocystis spp. by indirect fluorescent antibody tests. Overall, the proportion of seropositive animals was 6.4, 22.2, 42.2, 25.4, and 50.8 % for brucellosis, leptospirosis, neosporosis, toxoplasmosis, and sarcocystosis, respectively. The proportion of seropositive animals for all diseases was statistically different among herds (p?<?0.05). Statistical differences were also detected among age groups for brucellosis and neosporosis (p?<?0.05). The detection of specific antibodies to B. abortus, Leptospira spp., and several Apicomplexa protozoans in water buffaloes in the NEA is reported in this study.  相似文献   
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