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91.
Temperature and relative humidity (RH) are the most important environmental factors affecting the sensory quality of fresh produce, and therefore, the consumer acceptability for fruits and vegetables displayed in a produce department. Poor temperature management inevitably occurs in commercial handling and reduces the quality and maximum potential shelf life of fruits and vegetables. Since there is a lack of information on the actual temperatures registered inside local distribution trucks or in consumer retail displays, and the effects on the produce quality, the current study was designed to evaluate the segment of the distribution chain that comprises the time the produce arrives from the distribution center to the store, is displayed at the store, and then stored under household conditions. Temperature and RH were recorded in three different produce departments, at reception and during a 6-week retail display period. Truck and produce temperatures were collected immediately upon opening of the doors, and display temperatures were monitored inside 27 refrigerated and non-refrigerated retail displays. Visual quality of 37 different produce items was evaluated, and surface or pulp temperatures were measured immediately upon unloading from the delivery truck. Reasons for produce waste were recorded on a daily basis during a 6-week period. Shelf life studies were conducted under simulated household conditions using samples collected at the stores. Results from this study showed that chilling-sensitive commodities were transported under too cold conditions, whereas heat-sensitive commodities were transported under too warm conditions. Visual quality of the produce received at the store ranged from good to poor depending on the fruit or vegetable evaluated, with raspberry receiving the lowest visual quality score in 6.7% of store deliveries, and banana, fresh-cut vegetables, peach and pineapple receiving the best visual quality score in 100% of store deliveries. Temperatures measured inside retail displays showed a wide variation, depending on the store and location inside the display, ranging from ?1.2 °C to 19.2 °C in refrigerated displays and from 7.6 °C to 27.7 °C in non-refrigerated displays. RH ranged from 55.9% to 92.9% in refrigerated displays and from 29.7% to 86.6% in non-refrigerated displays. Poor temperature management was the major cause of produce waste (55%) whereas expired date and mechanical damage accounted for 45% of the produce wasted. Results from this study show that fruits and vegetables are often handled under adverse environmental conditions, resulting in produce with poor quality and shorter shelf life, and increased waste at the retail and consumer levels.  相似文献   
92.
A case of leishmaniasis in a domestic cat (Felis domesticus) is described. The animal showed a single, nodular lesion on the nose and many nodules of different size on the ears and digital regions of all the paws. Diagnosis was made by microscopic detection of amastigotes in Giemsa-stained smears from the lesions. By monoclonal antibodies the aetiological agent was identified as Leishmania (Leishmania) amazonensis, one of the seven species implicated in human leishmaniasis in Brazil. The clinical signs in feline leishmaniasis are unspecific and similar to those observed in other diseases such as cryptococcosis and in sporotrichosis, commonly found in cats. Leishmaniasis should therefore, be added to the differential diagnosis by feline veterinary practitioners and adequate investigations should carried out for dermal leishmaniasis in the area where the feline infection is detected.  相似文献   
93.
Objective: To evaluate the cardiorespiratory effects of continuous infusion of ketamine in hypovolemic dogs anesthetized with desflurane. Design: A prospective experimental study. Animals: Twelve mixed breed dogs allocated into 2 groups: saline (n=6) and ketamine (n=6). Interventions: After obtaining baseline measurements (time [T] 0) in awake dogs, hypovolemia was induced by the removal of 40 mL of blood/kg over 30 minutes. Anesthesia was induced and maintained with desflurane (1.5 minimal alveolar concentration) and 30 minutes later (T75) a continuous intravenous (IV) infusion of saline or ketamine (100 μg/kg/min) was initiated. Cardiorespiratory evaluations were obtained 15 minutes after hemorrhage (T45), 30 minutes after desflurane anesthesia, and immediately before initiating the infusion (T75), and 5 (T80), 15 (T90), 30 (T105) and 45 (T120) minutes after beginning the infusion. Measurements and main results: Hypovolemia (T45) reduced the arterial blood pressures (systolic arterial pressure, diastolic arterial pressure [DAP] and mean arterial pressure [MAP]), cardiac (CI) and systolic (SI) indexes, and mean pulmonary arterial pressure (PAP) in both groups. After 30 minutes of desflurane anesthesia (T75), an additional decrease of MAP in both groups was observed, heart rate was higher than T0 at T75, T80, T90 and T105 in saline‐treated dogs only, and the CI was higher in the ketamine group than in the saline group at T75. Five minutes after starting the infusion (T80), respiratory rate (RR) was lower and the end‐tidal CO2 (ETCO2) was higher compared with values at T45 in ketamine‐treated dogs. Mean values of ETCO2 were higher in ketamine than in saline dogs between T75 and T120. The systemic vascular resistance index (SVRI) was decreased between T80 and T120 in ketamine when compared with T45. Conclusions: Continuous IV infusion of ketamine in hypovolemic dogs anesthetized with desflurane induced an increase in ETCO2, but other cardiorespiratory alterations did not differ from those observed when the same concentration of desflurane was used as the sole anesthetic agent. However, this study did not evaluate the effectiveness of ketamine infusion in reducing desflurane dose requirements in hypovolemic dogs or the cardiorespiratory effects of ketamine–desflurane balanced anesthesia.  相似文献   
94.
1. Three experiments were conducted to evaluate the effects of the dietary addition of fungal phytase (derived from Aspergillus niger) on the performance and phosphorus utilisation in broiler chickens receiving low phosphorus diets without additional inorganic phosphates.

2. Graded amounts of supplemental phytase (125, 250, or 500 PU/kg diet) resulted in significant increases in both growth rate and food intake. However, only moderate improvements in food conversion were noted.

3. The enhancement of chick performance was related to an improved utilisation of dietary phosphorus, as confirmed by significantly elevated plasma concentrations of inorganic phosphorus and increased tibia ash percentages in birds receiving phytase‐treated diets. The apparent availability of phosphorus was markedly improved and its concentration in excreta was reduced (experiment 1, P<0.05).

4. It was concluded that an inclusion of phytase into practical broiler diet will allow the reduction or omission of additional dietary inorganic phosphorus.  相似文献   

95.
Canine babesiosis is an infectious disease caused by either Babesia gibsoni or Babesia canis protozoans. The latter is also classified under three different phylogenetic groups, referred to as subspecies B. canis canis, B. canis vogeli and B. canis rossi. The objective of the present study was to validate and standardize a PCR assay to discriminate the organisms at the subspecies level. First, the reference sequences of the 18S rRNA, 5.8S rRNA and 28S rRNA genes, including the internal transcribed spacer 1 (ITS1) and 2 (ITS2) of the most common species and subspecies of the genus Babesia were retrieved from the GenBank database. Subspecies-specific primers (BAB3, BAB4 and BAB5) and one genus-specific primer were designed from the alignment of the sequences. The PCR assays were evaluated in three different combinations of primer pairs in order to assure complete specificity for each reaction. The results of the tests had demonstrated effectiveness of the novel primer pairs BAB1/BAB3, BAB1/BAB4 and BAB1/BAB5 for the amplification of the subspecies-specific target fragments of 746 bp (B. c. canis), 546 bp (B. c. vogeli) and 342 bp (B. c. rossi) by PCR. The original enzymatic amplification assays with novel primers reported in this paper were confirmed to be a reliable tool for the specific discrimination among B. canis subspecies by single-step PCR assays.  相似文献   
96.
The aim of this study was to evaluate the correlation between the cerebral state index (CSI) and the estimated propofol plasma concentrations in dogs during induction of anaesthesia. Fifteen healthy dogs undergoing scheduled routine surgical procedures were enrolled in this study. Target controlled infusion (TCI) software, based on the pharmacokinetic model for propofol, was used to control the syringe pump and to estimate plasma propofol concentrations (PropCp) and the CSI values every five-seconds. Three electrodes placed in the centre of the forehead, on the left side of the forehead and on the left mastoid were used to collect the electroencephalographic (EEG) signal converted by the cerebral state monitor into the CSI. The cerebral electrical changes induced by increasing propofol concentrations appear to be detected by CSI monitoring in dogs. The negative correlation between CSI and PropCp demonstrates that the CSI could be used to assess electrical brain activity in dogs during the induction of anaesthesia with propofol.  相似文献   
97.
The detection of mycotoxins in feeds and their ingredients in aquaculture gained prominence due to losses caused in production and animal health, mainly the occurrence of aflatoxin (AFB1). The aim of this study was to evaluate the effects of AFB1 on the performance of tambaqui fingerlings (Colossoma macropomum). Four hundred tambaqui were used. Four different treatments were evaluated: treatment T1, considered as the control treatment (CT) with 3.84 μg kg−1; treatment T2, treatment T3 and treatment T4 with 500, 1000 and 2000 μg kg−1 of AFB1, respectively. The AFB1 of the samples (muscle, liver and kidney) was detected by high-pressure liquid chromatography. Four fingerlings from each treatment for histological analysis were examined. Moreover, the performance parameters (weight gain, feed conversion and feed intake) were studied. The levels of toxins used in T2, T3 and T4 represent a reduction in the growth of 14%, 35% and 45%, respectively. The T3 and T4 showed the lowest weight gain (78%) and the worst feed conversion. Aflatoxin B1 in muscle (3.28 μg kg−1) and kidneys (8.8 μg kg−1) in the T3, as well as liver (4.4 μg kg−1) and kidney (4.08 μg kg−1) in T4, was detected. Histopathological changes in liver and kidney tissues of fingerlings were more pronounced in T3 and T4. Fingerlings that consume feed contaminated with AFB1 in concentrations higher than 500 μg kg−1 present decreases in growth, reduction in weight gain and feed intake with increased feed conversion. The consumption of feed contaminated with 1000 and 2000 μg kg−1 of AFB1 caused severe deterioration in the hepatic and renal tissues.  相似文献   
98.
In Brazil, mussel seed are not a plentiful natural resource, and so the efficient use of seeds by reducing stocking densities should be considered. There are very few studies addressing the relationship between seeding density and growth of mussels in tropical conditions. This work aimed to determine the influence of low seeding densities on the productive performance of Perna perna (Linnaeus) mussels cultivated on ropes in Caraguatatuba, Brazil. In October 2014, 12 ropes, one metre in length each, were seeded at the densities of 200, 300 and 400 mussels/m (four ropes for each density) and suspended on a long line. After 226 days of growing, mussels were harvested and their performance at each density was evaluated in terms of mean weight and length, production, culture efficiency, condition index, survival, amount of recruited seed, amount of fouling on the ropes and morphometric relationships. We observed no significant differences (p > .05) for these indicators among the densities tested, except for mussel biomass, which was significantly higher (p < .05) at the greater densities. A partial budget analysis showed that the density of 400 m?1 showed better profitability and should be recommended, even in case of seed shortage.  相似文献   
99.
In an increasingly anthropic world, humans have profound impacts on the distribution and behaviour of marine fishes. The increased human presence has modified fishes’ antipredator behavioural responses, and consequently flight decisions, as a function of their changed perceptions of risk. Understanding how fish react to human presence can help identify the most vulnerable functional groups/species and estimate impacts caused by human disturbance. Shoal and body size are known to influence fish flight initiation distance (FID; the distance between the predator and prey when the prey begins to escape); however, few studies attempt to test the moderators of these relationships. Here, we present a comprehensive meta‐analysis evaluating FID of fish in response to human presence. Specifically, we investigated six candidate moderators that could influence the relationship between FID with shoal and body size. Our results showed that individual fish size was strongly and positively correlated with FID and the most important moderator that explained the variance in individual body size‐FID relationship was shoaling behaviour. However, and somehow surprisingly, we detected no significant relationship between shoal size and FID. We discuss how these results can inform the development of fish conservation strategies and ultimately assist in the management of marine protected areas.  相似文献   
100.
This study evaluated the addition (0.35 and 0.70 g/kg feed) of clove (EOcl) or cinnamon (EOci) essential oils to Nile tilapia feed for 45 days to assess animal performance, antioxidant capacity and lipid oxidation in fillets. The design was completely randomised with five treatments and three replicates. Antioxidant capacity was determined by the oxygen radical absorbance capacity (ORACFL), 2,2‐diphenyl‐1‐picrylhydrazylhydrate (DPPH), ferric reducing ability power (FRAP) and 2,2’‐azino‐bis (3‐ethylbenzothiazoline‐6‐sulphonic acid) (ABTS) assays, and lipid oxidation was determined by the thiobarbituric acid‐reactive substances (TBARs) assay. Animal performance was not altered by adding the essential oils. The fillets treated with 0.35 g/kg of EOcl presented higher antioxidant capacity in the L‐ORACFL assay and a 40.3% reduction in lipid oxidation, whereas the EOci provided a pro‐oxidant effect relative to the control treatment. Based on these results, adding 0.35 g/kg of EOcl to the diet for 45 days before slaughter increased the antioxidant capacity and reduced the lipid oxidation of the fillets, contributing to product quality without altering animal performance.  相似文献   
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