A. Florczyk  H. Simhofer  J. Rosser 《Equine Veterinary Education》2020,32(7):368-371

Hypothermia is a common, detrimental post-operative complication in man and veterinary medicine. Active warming strategies are paramount for prevention and treatment. Duration of operations, administered drugs and their adverse effects put horses undergoing procedures requiring long-standing sedation in danger of hypothermia. The aim of this study was to investigate whether an air warming device would be helpful to avoid severe hypothermia in adult horses. Twenty client-owned horses undergoing dental/sinusoidal procedures were divided into two equal groups. The treatment group was covered with a warming blanket connected to the warming device with the temperature set to 43°C. Horses in the control group were not blanketed. Temperature was measured at the time of first sedation (T0) and every hour throughout the length of the procedure. Use of the warming blanket was straightforward and caused no adverse reactions. The mean decrease in body core temperature in the treatment group was significantly less than the mean temperature decrease in the control group, beginning at the second hour of the procedure. No horse in the treatment group reached a body temperature below 36°C. Overall loss of temperature in the control group was more than double when compared with the treatment group (1.5°C and 0.7°C respectively). The use of an active air warming blanket in horses is an easy technique to prevent hypothermia in horses undergoing long-standing sedation procedures.  相似文献   

    

A. B. M. Rijkenhuizen  D. Lichtenberg  K. Weitkamp 《Equine Veterinary Education》2020,32(8):e130-e135

This case report describes the laparoscopic approach for removal of cystic intra-abdominal testicles in the standing colt. One 3-year-old Tobiano and one 2-year-old Warmblood colts were referred for abdominal cryptorchidectomy. The horses were clinically and ultrasonographically examined and a presumptive diagnosis of unilateral abdominal cryptorchidism was made. A laparoscopic approach via the flank was used to localise each abdominal testicle. In both colts the abdominal testicle was enlarged and cystic. Each spermatic cord was ligated and fluid was aspirated from the testicle. By reducing the size of the mass minimally invasive removal through an enlarged instrumental portal was possible. Histopathology revealed a cystic rete testis in the Tobiano and a teratoma in the Warmblood. In these cases the cystic enlarged testicles were nonpainful and were incidental findings. A cystic testicle might be developmental (Tobiano case) or arise due to neoplastic transformation (Warmblood case). The laparoscopic approach for enlarged cyst-like testicles in the standing horse offers a secure minimally invasive method for removal.  相似文献   

    

Collin E. Beachum  Matt J. Michel  Jason H. Knouft 《Ecology of Freshwater Fish》2020,29(2):210-219

Predicting the potential effects of changes in climate on freshwater species requires an understanding of the relationships between physiological traits and environmental conditions among populations. While water temperature is a primary factor regulating metabolic rates in freshwater ectotherms, how metabolic rates vary across the species range is unclear. In addition, photoperiod has also been hypothesised to influence metabolic rates in freshwater taxa based on seasonal changes in activity rates. Using an experimental approach, we investigated whether variation in routine metabolic rate (RMR) and sensitivity of RMR to changes in temperature are correlated with local thermal regimes, photoperiods and body mass among ten populations across the geographic range of the Bluntnose minnow (Pimephales notatus), a North American freshwater fish species. Routine metabolic rate data were collected from populations acclimatised to three temperature treatments (9, 18 and 27°C) and correlated with water temperature and photoperiod estimates at collection locations for each population. Routine metabolic rate was negatively correlated with minimum photoperiod at 9°C, negatively correlated with weekly high temperature at 18°C and positively correlated with weekly high temperature at 27°C. Body mass was also a predictor of RMR at each temperature treatment. Thermal sensitivity of RMR was positively correlated with weekly high temperature, indicating that individuals from warmer low latitude populations experienced greater sensitivity of RMR to changes in temperature than individuals from cooler high latitude populations. These results indicate differential responses among populations to variation in temperature and suggest the importance of recognising this variation when characterising responses of freshwater taxa to increases in water temperature.  相似文献   

    

Lou Frotté  Julien Ringelstein  Dominique Monti  Marie Robert  Christophe Pécheyran  Nadia Améziane  Hélène Tabouret 《Ecology of Freshwater Fish》2020,29(1):132-144

All native fishes living in the Caribbean island rivers are considered diadromous but few species have been validated as diadromous. In Guadeloupe (Lesser Antilles) as well as in the other tropical islands, the riverine habitats are subject to strong anthropogenic pressure due to resource modifications or dams. The management of fish biodiversity requires knowledge concerning their life history traits and behaviour that are still unknown for most species at a local scale and at the whole distribution area of the species. In a Guadeloupe river, we inferred the migratory patterns of four freshwater fishes common to Caribbean rivers by the analysis of otolith microchemistry. We found two species Eleotris perniger (Eleotridae) and Sicydium plumieri (Gobiidae) to be completely amphidromous with a marine larval phase and a freshwater adult phase. Agonostomus monticola (Mugilidae) was also found to be amphidromous in this system. The fourth species Gobiesox cephalus (Gobiesocidae) showed elemental ratios suggesting an estuarine larval phase and was defined as “limited amphidromous”. The identification of such life history traits, with limited dispersion abilities, argues for specific management measures in tropical island rivers at a basin scale for the conservation of biodiversity.  相似文献   

    

Rebecca R. Gentry  Heidi K. Alleway  Melanie J. Bishop  Chris L. Gillies  Tiffany Waters  Robert Jones 《Reviews in Aquaculture》2020,12(2):499-512

Marine aquaculture is growing quickly and has substantial effects on people and the environment. Existing research has demonstrated that marine aquaculture can contribute to ecosystem service provisioning that extends beyond production of a resource; however, the extent and significance of these goods and services are not well understood. Here we review existing knowledge of ecosystem service provision by marine aquaculture by systematically examining 129 peer reviewed papers that describe the provision of nine distinct ecosystem services by operational or experimental marine aquaculture farms. We quantify service provision and classify services by type and by farm characteristics. We show that while certain services, such as nutrient absorption by kelp aquaculture, are well understood and have been documented across multiple species, scales and environments, the evidence for other services, such as the cultural service of tourism, is currently minimal. Importantly, we identify ecosystem services associated with a diversity of farm types (including fish, bivalve, algae and polyculture farms) but find that certain services were most often delivered by specific farm types (e.g. habitat services were most often associated with fish farms). Incorporating acknowledgement of ecosystem services into farm design and planning has the potential to improve environmental performance and sustainable management of aquaculture. However, outstanding questions, including how spatial expansion of marine aquaculture will affect the provisioning of these services, are important challenges facing sustainable development.  相似文献   

    

Samuel Bekele Mengistu  Han A. Mulder  John A. H. Benzie  Hans Komen 《Reviews in Aquaculture》2020,12(2):524-541

Productivity among small‐ and medium‐scale tilapia farms varies considerably. The difference between the best performers and lower ones (yield gap), is affected by differences in growth rate and feed conversion ratio (FCR). FCR at the farm level is strongly influenced by survival of fish. In this study a systematic literature review of two databases (ASFA and CAB‐Abstracts) identified 1973 potentially relevant articles. Data from 32 articles that met the inclusion criteria were analysed using linear mixed models for the most important factors with significant contributions to growth [investigated through analysis of the thermal growth coefficient (TGC)], survival and FCR of Nile tilapia. Increasing crude protein (CP), dissolved oxygen (DO) and pH significantly decreased FCR and increased TGC. Increasing stocking weight (SW) significantly improved both FCR and survival. Temperature had the largest effect on FCR followed by DO, pH and CP. DO had the largest effect on TGC followed by CP and pH. This study confirms that the optimal rearing temperature for Nile tilapia is between 27 and 32°C. Improving management to optimize DO (> 5 mg/L), stocking density (3–5 fish/m²), SW (> 10 g) and CP (25 − 30%) will improve performance and survival in small‐ and medium‐scale tilapia farming. However, it is hard to influence temperature in ponds and cages while DO is largely influenced by aeration. Since many small‐ and medium‐sized farms do not have aeration, these major tilapia farming systems could benefit from genetically improved strains selected for resilience to highly fluctuating diurnal temperature and DO levels.  相似文献   

    

Vincenzo A. Laudicella  Phillip D. Whitfield  Stefano Carboni  Mary K. Doherty  Adam D. Hughes 《Reviews in Aquaculture》2020,12(2):678-702

Bivalve production is a relevant aquaculture activity in Europe; however, it is not developing with same extents of other aquaculture sectors due to causes connected with regulation stringency, labour cost, space availability, habitat loss as well as variability in recruitment events, climate change and diseases. Understanding the physiology and nutritional requirements of bivalves during aquaculture activities might result beneficial to fuel up the development of the sector. Lipids are important molecules as they are relevant components of cellular membranes acting in several physiological processes like reproduction, growth, immunological responses and energy reserve. Nevertheless, lipid diversity is still poorly understood despite the research efforts of the last decades. Technological advancements provide tools to unveil such diversity. Lipidomics, a branch of metabolomics, is the science targeting the lipidome (e.g. the totality of biological lipids in an organism). In this review, lipidomics, and its related concepts, are discussed providing an overview of recent lipidomics studies on bivalves. Lipidomics could result in several advantages if compared with traditional lipid profiling techniques; however, aims and scopes of future lipidomics studies should be expanded. Here, possible future applications of lipidomics in the context of bivalve production are presented and discussed. Unveiling the lipidome of marine bivalves could aid disclosing important information regarding nutrition, biology, physiology and epidemiology on bivalves. This knowledge, once applied, has the potential to improve bivalve production and the resilience of the sector to environmental changes.  相似文献   

    

Brett D. Glencross  Johanna Baily  Marc H.G. Berntssen  Ronald Hardy  Simon MacKenzie  Douglas R. Tocher 《Reviews in Aquaculture》2020,12(2):703-758

A wide range of raw materials are now used routinely in aquaculture feeds throughout the world, primarily to supply protein and energy in the form of lipid from edible oils. Protein meals and oils used can generally be divided into those of plant or animal origin and many have considerable potential to supply the required dietary nutrients required by aquaculture species. However, the use of any raw material introduces a suite of risks that need to be considered to enable the production of safe, sustainable and functional feeds to underpin this sector. A lack of understanding of some of those risks can result in failure of dietary specifications being met and/or negative nutritional elements being introduced (e.g. antinutritional factors). Importantly, it is this feed that when fed to food‐producing animals is such an important element of food safety, and as such any undesirable aspects relating to feed production can also have a negative impact on the rest of the food chain. However, there is some disparity internationally among raw materials that are used and the perceptions surrounding the risk of their use. It is the scientific assessment of these risks that is the basis of this review.  相似文献   

    

Derek P. Crane  Derek H. Ogle  Daniel E. Shoup 《Reviews in Aquaculture》2020,12(3):1542-1547

Growth is an important metric in fisheries and aquaculture. Growth of small fish over relatively short periods of time is commonly modelled with an exponential function using instantaneous growth rate (g). Instantaneous growth rates are logarithmic and inherently difficult to interpret, but specific growth rates (SGR) express growth as the intuitively understandable per cent change in size per unit of time. A simple metric of SGR (G) is easily computed by exponentiating g, subtracting 1 and multiplying by 100. However, several prominent fisheries publications suggest that SGR should be calculated by simply multiplying g by 100 (we call this G*). A search of the fisheries literature found that the number of papers that used SGR for fish increased significantly from 1830 papers in 2009 to 3170 papers in 2018. An extensive review of 300 papers from this search found that 92.6% were related to aquaculture and only 3.3% of all papers correctly used G to calculate SGR. We algebraically show that G* is fundamentally different than G and cannot be interpreted as a per cent change in weight per unit of time. Furthermore we demonstrate, with three examples from the literature, that using G* as if it were the same as G leads to biologically meaningful underestimates of true growth rates and estimated weights. Given these results and the simplicity with which G can be computed from g, we recommend that fisheries scientists abandon the pervasive practice of incorrectly measuring SGR as 100 times the instantaneous growth rate.  相似文献   

    

K. Obasa  A. Adesemoye  R. Obasa  D. Moraga-Amador  H. Shinogle  S. Alvarez  K. Kelley 《Plant pathology》2020,69(1):87-100

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