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61.
The Hazard Analysis and Critical Control Point (HACCP) monitoring system has been used traditionally to increase quality control in human food production operations and there is pressure to implement it at the producer and purchaser levels of the food chain. Recently, the concept of HACCP monitoring has extended to food fed to domestic animals. Captive wildlife facilities, such as zoos and aquaria, would benefit from a well‐organized, food safety and nutritional monitoring system. Zoos and aquaria spend significant resources in time and money on maintaining the health of their animals; much of this energy is focused on disease prevention and adequate nutrition. The result of these combined efforts is the implementation of a HACCP program in zoo food management. Although zoo food handling standards have been implemented through the American Zoo and Aquarium Association (AZA) accreditation process, food borne disease outbreaks and malnutrition still exist. By implementing an organized approach to monitoring the quality of food delivered to the animals, the safety and nutritional value of the foods will increase, while decreasing the financial loss due to food waste and time spent caring for ill animals. This report provides a framework for implementing a HACCP program into the food preparation and handling system of zoos and aquaria. Zoo Biol 0:1–11, 2005. © 2005 Wiley‐Liss, Inc.  相似文献   
62.
Despite its value as a crop and potential utility as an experimental system, relatively little is known about the molecular-genetic aspects of inheritance or physiology in the cultivated strawberry (Fragaria xananassa). This lack of information exists at a time when biotechnology may offer important remedies to address traditional and contemporary challenges that growers face. An improved understanding of genome structure will hasten the development of molecular markers and unveil clues to the composition of this unique, octoploid genome. Definition of gene function will guide the generation of transgenic resources for research use and possibly toward cultivar development. This review seeks to compile and present the current knowledge state of the molecular-genetic basis of cultivated strawberry genomic form and function. Ongoing studies promise to expand the use of genomic tools and appropriate model systems to rapidly discern the structural and functional basis for traits of interest to agriculture, such as those associated with disease, ripening, and volatile production. Together these studies bring new molecular tools to dissect complex traits, implement marker-assisted selection and address important physiological questions in the cultivated strawberry, the Fragaria genus, and the Rosaceae family.  相似文献   
63.
The rates of uptake of a range of forms of nitrogenous nutrients were measured in cultures of Pfiesteria piscicida and Pfiesteria shumwayae maintained at varying physiological states. The measured rates of dissolved N uptake under some conditions approached the rates of N uptake that are achieved through phagotrophy. Rates of dissolved N uptake by P. piscicida contributed <10% of the cellular N of flagellated cells feeding on algae, but were equal to or greater than phagotrophic N acquisition in cells recently removed from fish cultures. Specific N uptake rates (V, h−1) were higher for cells that were maintained on algal prey for long periods (months) than those that were grown with live fish. However, rates of N uptake on a cellular basis for cells grown on or recently removed from fish were comparable to those maintained on algal prey, likely reflecting differences in the sizes of cells of different physiological condition. Preferences for form of N generally followed a decreasing trend of amino acids > urea > NH4+ > NO3. Nitrate consistently was not a preferred form of N. Although Pfiesteria spp. are often found in eutrophic environments, the relationship between Pfiesteria spp. and nutrient availability is likely to be primarily indirect, mediated through the production of various prey on which Pfiesteria spp. feed. These findings also confirm, however, that when dissolved N concentrations are elevated, they can contribute to the supplemental nutrition of these cells, and thus may provide a significant source of N to Pfiesteria spp. in nature.  相似文献   
64.
The activation of the hypothalamic–pituitary axis is critical for the initiation and maintenance of reproductive cycles in pigs and is influenced by a number of factors, such as nutrition, metabolism and gonadal steroids. Kisspeptin is a neuropeptide that is expressed in discrete regions of the porcine hypothalamus and is positioned to mediate the action of many of these factors. The expression of kisspeptin in the pig hypothalamus does not appear to be regulated by gonadal steroids in the same way as other species. It is unclear if kisspeptin is mediating nutritional or metabolic effects on gonadotropin secretion in pigs as it takes large deficits in feed intake or BW to affect hypothalamic expression of the KISS1 gene in the porcine hypothalamus. There appears to be little genetic diversity in kisspeptin or its receptor that is useful for improving reproduction in swine. Both peripheral and central injection of kisspeptin strongly stimulates the secretion of gonadotropin hormones, LH and FSH, in gilts. Similarly, synthetic analogues have been developed and showed potential promise as tools to manage reproductive cycles in gilts and sows. Review of the literature nonetheless reveals that research on kisspeptin and its function in controlling reproduction in pigs has lagged that of other livestock species.  相似文献   
65.
Spineless cactus is a useful feed for various animal species in arid and semiarid regions due to its adaptability to dry and harsh soil, high efficiency of water use and carbohydrates storage. This meta-analysis was carried out to assess the effect of spineless cactus on animal performance, and develop and evaluate equations to predict dry matter intake (DMI) and average daily gain (ADG) in meat lambs. Equations for predicting DMI and ADG as a function of animal and diet characteristics were developed using data from eight experiments. The dataset was comprised of 40 treatment means from 289 meat lambs, in which cactus was included from 0 to 75% of the diet dry matter (DM). Accuracy and precision were evaluated by cross-validation using the mean square error of prediction (MSEP), which was decomposed into mean bias, systematic bias and random error; concordance correlation coefficient, which was decomposed into accuracy (Cb) and precision (ρ); and coefficient of determination (R2). In addition, the data set was used to evaluate the predicting accuracy and precision of the main lamb feeding systems (Agricultural and Food Research Council, Small Ruminant Nutritional System, National Research Council and Institut National de la Recherche Agronomique) and also two Brazilian studies. The DMI, CP intake (CPI), metabolizable energy (ME) intake and ADG increased when cactus was included up to 499 g/kg DM (P<0.001). In contrast, animals fed high levels of cactus (>500 g/kg DM) had a decreased DMI, CPI and NDF intake, but increased feed efficiency (P<0.001) and similar ADG compared with those without cactus addition. The DMI was positively correlated with initial BW, final BW, concentrate and ADG, while it was negatively correlated with cactus inclusion and ME of the diet. On other hand, ADG was positively correlated with DMI, initial and mean BW and concentrate, and it was negatively correlated with cactus inclusion. The two developed equations had high accuracy (Cb of 0.95 for DMI and 0.94 for ADG) and the random error of MSEP was 99% for both equations. The precision of both equations was moderate, with R2 values of 0.53 and 0.50 and ρ values of 0.73 and 0.71 for DMI and ADG, respectively. In conclusion, the developed equation to predict DMI had moderate precision and high accuracy, nonetheless, it was more efficient than those reported in the literature. The proposed equations can be a useful alternative to estimate intake and performance of lambs fed cactus.  相似文献   
66.
67.
BackgroundBiochemical assessment is considered a useful tool in assessing the patient’s nutritional status and intake. However, during critical illness, nutritional biomarkers, such as albumin, and haemoglobin (HB) may reflect the severity of acute illness. The aim of this study is to assess the relationship between energy and protein delivery with the change in albumin, HB, “mean corpuscular volume”(MCV), and “mean corpuscular haemoglobin concentration” (MCHC) levels in critically ill patients.MethodIn this prospective observational study we monitored the intake of energy and protein in a group critically ill patients for 6 consecutive days. Biochemical data including albumin, HB, MCV and MCHC was measured on admission and on day 6 of the follow-up. The variation in the biomarkers between admission and day 6 was calculated as the follow-up reading minus the reading obtained upon admission to (Intensive Care Unit) ICU.ResultsThis study included 43 patients. There was a significant difference in the albumin and HB levels between admission and follow up readings. No statistical association was recorded between the intake and the changes in albumin, MCV and MCHC level during ICU stay. The results showed a significant association between the intake of energy (R = 0.393), and protein (R = 0.385), with the increase in HB level during hospitalisation.ConclusionOverall, this study showed that most nutritional biomarkers were not influenced by nutritional therapy during the acute phase of illness. These findings may directly undermine the usefulness of the serial measurements of these biomarkers in the early phase of ICU admission.  相似文献   
68.
Across much of North America, populations of moose (Alces alces) are declining because of disease, predation, climate change, and anthropogenic-driven habitat loss. Contrary to this trend, populations of moose in Colorado, USA, have continued to grow. Studying successful (i.e., persistent or growing) populations of moose can facilitate continued conservation by identifying habitat features critical to persistence of moose. We hypothesized that moose using habitat with higher quality willow (Salix spp.) would have a higher probability of having a calf-at-heel (i.e., calving success). We evaluated moose calving success using repeated ground observations of collared individuals with calves in an occupancy model framework to account for detection probability. We then evaluated the impact of willow habitat quality and nutrition on moose calving success by studying 2 spatially segregated populations of moose in Colorado. Last, we evaluated correlations between willow characteristics (browse intensity, height, cover, leaf length, and species) and willow nutrition (dry matter digestibility [DMD]) to assess the utility of using those characteristics to assess willow nutrition. We found willow height and cover had a high probability of being positively associated with higher individual-level calving success. Willow DMD, browse intensity, and leaf length were not predictive of individual moose calving success; however, the site with higher mean DMD consistently had higher mean estimates of calving success for the same year. Our results suggest surveying DMD is likely not a useful metric for assessing differences in calving success of individual moose but may be of use at population levels. Further, the assessment of willow morphology and density may be used to identify areas that support higher levels of moose calving success.  相似文献   
69.
Hybridoma cells are featured by the effective utilization of both B lymphocytes and immortalized myeloma cells, allowing for the continuous generation of monoclonal antibodies specific to antigens. With regard to conventional hybridoma technology, B lymphocytes must be fused with myeloma cells using various methods to generate hybridoma cells. Nutrition plays an important role in hybridoma cell survival and amplification, which determines the fusion effect and antibody production. Here we compared the growth and survival rates of hybridoma in a commonly used peritoneal macrophage feeder layer (PMFL) nutrition supply system with a commercial hybridoma feeder additive (HFA) nutrition supply system at the post fusion stage and discussed the titer of monoclonal antibodies by enzyme linked immunosorbent assay (ELISA). Our results indicate that commercially available HFA promotes the survival and amplification of hybridoma clones and improves the titer of monoclonal antibodies indirectly.  相似文献   
70.
In the available literature, there are limited data about the energetic value of insect-derived products. In particular, insect fat cannot be used in practical broiler nutrition due to the lack of precise apparent metabolisable energy (AME) value. Therefore, the present study aimed to investigate the AME and apparent metabolisable energy corrected to zero nitrogen balance (AMEN) levels of Hermetia illucens larvae fat for broiler chickens of various ages. A total of 400 1-day-old male Ross 308 chicks were randomly allotted to four dietary groups (10 replicate pens per treatment; 10 birds per pen). The following treatments were applied: HI0 – basal diet without dietary fat inclusion, HI03 – basal diet enriched with 30 g/kg H. illucens larvae fat, HI06 – basal diet enriched with 60 g/kg H. illucens larvae fat, and HI09 – basal diet enriched with 90 g/kg H. illucens larvae fat. Broilers had ad libitum access to mash form feed and water. Excreta samples were collected on d 14, d 28, and d 35. To determine the AME and AMEN values of H. illucens larvae fat, the simple linear regression method was used. The results show that the AME and AMEN values of H. illucens larvae fat for broiler chickens are 9 049 kcal/kg (37.86 MJ/kg) and 9 019 kcal/kg (37.74 MJ/kg), respectively. Additionally, because the birds’ age significantly (P < 0.001) affected the AME and AMEN levels, the implementation of H. illucens larvae fat to broiler diets should be considered in each nutritional period using the recommended regression model AME = 2 559.758 + 62.989 × fat inclusion (%) + 7.405 × day of age and AMEN = 2 543.2663 + 62.8649 × fat inclusion (%) + 7.3777 × day of age. The present data emphasised that the H. illucens larvae fat metabolisable energy is similar to that of soybean oil.  相似文献   
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