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271.
The pharmacological effects of glargine, protamine zinc (PZI), and lente insulins were evaluated in nine healthy cats. A 3-way crossover study was performed and plasma concentrations of insulin and glucose were determined for 24 h after a single subcutaneous injection of each insulin at 3-day intervals.
Time to onset of action did not differ between insulins. Mean time to first nadir glucose was longer for glargine (14 h) relative to PZI (4 h) and lente (5 h). PZI was biphasic in action with nadirs at 4 and 14 h with the second nadir occurring at a similar time to glargine. Nadir glucose did not differ significantly between insulin types. The duration of action was similar for glargine and PZI and was longer than that for lente insulin. Mean daily glucose after glargine and PZI were also similar and were lower than after lente insulin.
Time to reach peak insulin did not differ between insulin types. Time to return to baseline insulin level for PZI was longer than glargine but did not differ significantly from lente.
In conclusion, healthy cats injected subcutaneously with glargine, compared to those injected with lente insulin, have a later glucose nadir and longer duration of action. Glargine and PZI had similar durations of action in study cats but a larger study is required to obtain precise comparisons of duration of action.  相似文献   
272.
Breeding from prepubertal females, known as juvenile in vitro embryo transfer (JIVET), reduces the generation interval and increases the rate of genetic gain in animal breeding programs. While the birth of the first lambs from prepubertal ewes occurred nearly 30 years ago; and there is considerable interest in the commercialization of this technology, its efficiency remains too low. The advent of in vitro production (IVP) of embryo resulted in the more widespread use of JIVET. Morphologic and metabolic differences coupled with reduced in vitro and in vivo development of oocytes derived from prepubertal animals have been reported. Research has been undertaken to optimize donor selection and hormone stimulation methods in an attempt to reduce the variability and increase the proportion of donors responding to hormone stimulation and increase oocyte developmental competence. Yet, this variation persists and the development of oocytes and embryos from prepubertal animals remains reduced when compared with adults. Recent improvements to JIVET, resulting from a modified hormone stimulation regime, have eliminated the failure of donors to respond to hormone stimulation, and increased both the number and developmental competence of oocytes harvested from very young prepubertal lambs. This increased efficiency has facilitated the incorporation of other reproductive technologies such as sperm sexing with JIVET, resulting in the birth of lambs of a pre-determined sex from prepubertal lambs. Increased rates of genetic gain in sheep breeding programs can be achieved by combining sexed sperm with oocytes obtained from lambs as young as 3–4 weeks of age. Continued increases in the efficiency of JIVET resulting from further improvements to hormone stimulation regimes and an increased understanding of the differences between oocytes from adult and prepubertal animals will result in the commercialization of this technology.  相似文献   
273.
The primary objective of this study was to determine whether a single measurement of intravaginal electrical resistance (VER), using the commercially available Ovatec® probe, can discriminate between dioestrus and oestrus in Bos indicus females, which had been treated to synchronize oestrus. Santa Gertrudis heifers (n = 226) received one of three oestrous synchronization treatments: double PGF 10 days apart, 8‐day controlled internal drug release (CIDR) treatment or CIDR pre‐synchronization + PGF 10 days after CIDR removal. The heifers were inseminated within 12 h following observed oestrus, or, if not observed, at a fixed time approximately 80 h, following the last synchronization treatment. They were palpated per rectum for signs of pregnancy 9 weeks after artificial insemination (AI). Vaginal electrical resistance measurements were taken at the completion of synchronization treatments (presumed dioestrus), immediately prior to AI (oestrus), and then at 3 and 9 weeks post‐AI. Mean VER differed between presumed dioestrus and oestrus (113.7 vs 87.4, p < 0.001). The area under the receiver operating characteristics (ROC) curve was 0.925, indicating that VER was highly discriminatory between dioestrus and oestrus. Vaginal electrical resistance at time of AI was negatively associated with odds of conception when all inseminations were included in the analyses [odds ratio (OR) = 0.97; 95% CI 0.95–1.00; p = 0.018], but not when fixed time AIs were excluded (OR = 1.00; 95% CI 0.97–1.03; p = 0.982). Mean VER readings differed between pregnant and non‐pregnant animals at both 3 weeks (120.5 vs 96.7, p < 0.001) and 9 weeks (124.0 vs 100.3, p < 0.001) post‐AI. However, 3‐ and 9‐week VER measurements were not highly discriminatory between pregnancy and non‐pregnancy (area under ROC curve = 0.791 and 0.736, respectively). Mean VER at time of AI for animals diagnosed in oestrus differed between each of the oestrous synchronization treatments (84.7, 73.6 and 78.9, groups 1–3 respectively, p < 0.001). These findings suggest that measurement of VER may improve accuracy of oestrus diagnoses when selecting cattle for AI following oestrous synchronization programmes involving tropically adapted cattle.  相似文献   
274.
Outbreaks of nosocomial Salmonella infections in hospitalised horses can occur when surveillance and infection control protocols are not in place, or not well structured and enforced. The aim of this article is to present a review of published studies that have contributed to the literature of the epidemiology and infection control aspects of nosocomial Salmonella infections in hospitalised horses. The review highlights important elements that must be taken into consideration during the formulation, implementation and evaluation of a hospital surveillance and infection control programme designed to reduce the risk of an outbreak of nosocomial Salmonella infection in hospitalised horses.  相似文献   
275.
The science of ecology is undergoing many important shifts in emphasis and perspective which have important implications for its role in designing sustainable farming systems. In particular, a shift has occurred from the equilibrium paradigm to one which recognises the dynamic, non-equilibrium nature of ecosystems. Allied to this is the recognition that ecosystems can occur in any one of a number of alternative stable states, depending on the disturbance and management history. An increased emphasis on spatial patchiness in ecosystems has also emerged as appropriate tools have emerged to analyse spatial mosaics. These features have led to a recognition that considerable uncertainty is associated with the outcome of any particular ecosystem modification; hence predictive capacity is also low. Recent considerations of the interrelation between biodiversity and ecosystem function have also explored the questions of how many species need to be in a system to fulfil certain functions and confer resilience. We identify a set of steps that are required for the development of an agricultural system based on mimicking natural ecosystems. Central to this is identifying (1) the functions which are currently suboptimal in the agricultural system, and (2) the species which have key functional roles in the natural system, and then reaching decisions as to the array of species needed to confer system function and resilience.  相似文献   
276.
Coastal Social–Ecological Systems (SESs) are subject to several stresses, including climate change, that challenge fisheries and natural resource management. Fishers are front‐line observers of changes occurring both on the coast and in the sea and are among the first people to be affected by these changes. In this study, we perform a meta‐analysis of observations and adaptations to climate change by subsistence‐oriented coastal fishers extracted from a global review of peer‐reviewed and grey literature. Fishers' observations compiled from across the globe indicate increased temperatures and changes in weather patterns, as well as coastal erosion, sea level rise and shifts in species range and behaviours. Coastal areas offer a wide array of resources for diversifying livelihoods, but climate change is reducing these options. Specifically, climate change could reduce the resilience of fishers' communities, limiting options for diversification or forcing fishers to abandon their houses or villages.  相似文献   
277.
Agriculture is a major cause of non-point source water pollution in the Midwest. Excessive nitrate, phosphorous, and sediment levels degrade the Mississippi River and Gulf of Mexico. In this research we ask, to what extent can citizen involvement help solve the problem of non-point source pollution. Does connecting farmers to farmers and to other community members make a difference in moving beyond the status quo? To answer these questions we examine the satisfaction level of Iowa farmers and landowners with their current conservation measures as a proxy for willingness to change. A survey of 360 conservation minded farmers obtained from a random sample of 75 HUC (Hydrologic Unit Code) 12 Iowa watersheds reveals that 27% of the variance among farmers’ perception of adequacy of their conservation practices is explained by a combination of beliefs about the seriousness of water pollution, personal, civic, and expert connections. The more farmers talk with other farmers the more likely they are satisfied with their conservation efforts. However, the more frequently farmers talk to friends and neighbors that don’t farm, the more likely they are to not be satisfied with their conservation efforts. Further, the more social organizations farmers belong to—e.g., more non-farmers they interact with in a group setting—the more likely they are to be dissatisfied with their level of effort being adequate to protect local water bodies. These findings suggest the personal and civic connections among farmers and communities are important in explaining perceptions of how adequate conservation measures are. These perceptions have implications for farmers’ willingness to go beyond current actions and more actively engage in solving local watershed problems and explain why they may not currently be engaged in additional actions.  相似文献   
278.
The objective was to study the role of calpains in meat tenderness. Lambs were fasted for various periods of time to generate differences in meat tenderness and to determine in tandem the expression of calpain 1, calpain 2, calpain 3, and calpastatin. The assumption has been that increased calpain expression associated with an increase in tenderness indicates a role for calpain in the tenderization process and vice versa. Fasting lambs for 1 day caused a significant improvement in longissimus (LD) tenderness compared to the control. Correlations between the tenderness of the LD and the expression of the calpains and calpastatin were significant for calpains 1 and 3 but not for calpain 2 or calpastatin. Consequently, this study supports a role for calpains 1 and 3, but not for calpain 2, in the tenderization of the LD from fasted lambs during post-mortem aging.  相似文献   
279.
A quantum computer requires systems that are isolated from their environment, but can be integrated into devices, and whose states can be measured with high accuracy. Nuclear spins in solids promise long coherence lifetimes, but they are difficult to initialize into known states and to detect with high sensitivity. We show how the distinctive optical properties of enriched (28)Si enable the use of hyperfine-resolved optical transitions, as previously applied to great effect for isolated atoms and ions in vacuum. Together with efficient Auger photoionization, these resolved hyperfine transitions permit rapid nuclear hyperpolarization and electrical spin-readout. We combine these techniques to detect nuclear magnetic resonance from dilute (31)P in the purest available sample of (28)Si, at concentrations inaccessible to conventional measurements, measuring a solid-state coherence time of over 180 seconds.  相似文献   
280.
Growth rate is an important factor in neonatal survival. The aim of this study was to determine growth rates in hand-reared cheetah cubs in South Africa fed a prescribed energy intake, calculated for growth in the domestic cat. Growth was then compared with previously published data from hand-reared cubs in North America and the relationship between growth and energy intake explored. Daily body weight (BW) gain, feed and energy intake data was collected from 18 hand-reared cheetah cubs up to 120 days of age. The average pre-weaning growth rate was 32 g/day, which is lower than reported in mother-reared cubs and hand-reared cubs in North American facilities. However, post-weaning growth increased to an average of 55 g/day. Growth was approximately linear prior to weaning, but over the entire age range it exhibited a sigmoidal shape with an asymptotic plateau averaging 57 kg. Energy intake associated with pre-weaning growth was 481 kJ ME/kg BW(0.75). Regression analysis described the relationship between metabolic BW, metabolisable energy (ME) intake, and hence daily weight gain. This relationship may be useful in predicting energy intake required to achieve growth rates in hand-reared cheetah cubs similar to those observed for their mother-reared counterparts.  相似文献   
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