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271.
1. An experiment was conducted to quantify the extent of variability in the texture of cooked poultry breast meat and to attempt to identify which intrinsic and extrinsic factors contribute to this.

2. Free range (FR) and standard (STD) broilers were killed and processed under commercial conditions and the M. pectoralis major muscle assessed for ultimate pH (pHu), sarcomere length, cooking loss and texture 24 h and 7 d after slaughter.

3. Although FR broilers were females with an average age of 60 d, whereas the STD broilers were 45 d old and predominantly male, there were no significant differences in mean values obtained for pHu, sarcomere length, cooking loss and shear force results between the two bird types.

4. While aging for 7 d increased the pHu and cooking loss means, sarcomere length means remained unchanged and shear force values decreased by 6% and 9% for FR and STD birds respectively.

5. Variability in shear force values also decreased on aging for 7 d, no birds having values above 4 kg/cm2 on day 7 whereas 16% were above this value on day 1.

6. There were significant correlations between the results for shear force, pHu and sarcomere length, indicating that increased shear force values were associated with a decrease in both pHu and sarcomere length.

7. These correlations suggest that variability in the texture of cooked M. pectoralis major from FR and STD chickens is strongly influenced by those post‐mortem biochemical changes which lead to the development of rigor during the early stages of processing.  相似文献   

272.
CASE DESCRIPTION: A 21-year-old neutered male captive California sea lion developed chronic polyuria; polydipsia; polyphagia; accelerated development of existing cataracts; and frequent episodes of gastrointestinal upset including anorexia, signs of abdominal discomfort, diarrhea, and vomiting. CLINICAL FINDINGS: Chronic hypercholesterolemia, hypertriglyceridemia, hyperglycemia, and glucosuria were identified. During episodes of gastrointestinal abnormalities, transient hyperbilirubinemia and increased serum J-glutamyltransferase activities developed. Clinical findings strongly suggested chronic pancreatitis with secondary diabetes mellitus and intermittent cholestasis. Multiple diagnostic tests, including abdominal ultrasonography, serial hematologic and serum biochemical analyses, fecal examinations, urinalyses and bacteriologic culture of urine, measurement of serum fructosamine and insulin concentrations, and evaluation of thyroid and adrenal function, did not reveal any specific parasitic, endocrine, hepatic, or neoplastic etiologies. TREATMENT AND OUTCOME: For 1.5 years, the sea lion received once-daily administration of glargine insulin, gastrointestinal protectants, and a strict high-protein, low-fat diet. Daily monitoring of glucose regulation was achieved by training the sea lion to submit to blood and urine sampling. Glucose regulation ranged from fair to good, and clinical signs of diabetes mellitus lessened. Episodes of gastrointestinal upset still occurred, although the frequency and severity decreased. Ultimately, a severe episode developed, associated with diabetic ketoacidosis and sepsis, and the sea lion died. Severe fibrosing pancreatitis with exocrine and endocrine atrophy and abscesses arising from ectatic pancreatic ducts were found. Peripancreatic fibrosis caused stricture of the common bile duct, resulting in gallbladder distension without cholecystitis. CLINICAL RELEVANCE: Diabetes mellitus can occur secondary to chronic pancreatitis in California sea lions and insulin therapy should be considered.  相似文献   
273.
Persistent canine nasal disease is a common complaint in small animal practice; however, an etiologic diagnosis can be difficult to establish. The aim of this retrospective study was to determine the percentage of cases for which the etiology was determined in our hospital population. Medical records from 80 dogs met the criteria of inclusion in the study. Nonspecific rhinitis was identified in 23.7% of cases. Other diagnoses were neoplasia (15.0%), fungal infection (nasal aspergillosis) (8.7%), cleft palate (8.7%), periodontal disease (4.0%), parasites (1.3%), foreign body (1.3%), and primary bacterial disease (1.3%). A definitive diagnosis could not be established in 36.3% of cases. Dogs with neoplastic and mycotic diseases often presented with severe radiographic and rhinoscopic lesions. Despite a systematic approach, numerous cases went undiagnosed. The use of advanced imaging should increase our ability to obtain an etiologic diagnosis in canine nasal disease.  相似文献   
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The People's Republic of China‐Global Environment Facility Partnership to Combat Land Degradation in Dryland Ecosystems promotes an integrated ecosystem management (IEM) approach to restore, sustain and enhance the productive capacity of dryland ecosystems. This paper provides an analysis and synthesis of the funding strategies, methods and approaches that have been applied and tested under the Partnership to pilot and scale up IEM and sustainable land management (SLM) practices in the western People's Republic of China under its first 10 years. On the basis of a mix of methods using literature reviews, data collection at selected pilot sites through household questionnaire surveys, stakeholder workshops and field sampling, the following lessons were generated: (i) mainstreaming of IEM into relevant policy and development frameworks has been the most effective way of mobilizing funding for scaling up of SLM; (ii) SLM best practices need to be combined with economic incentives for land users, and pilot demonstrations of SLM need to be integrated into larger investment programmes to achieve impacts and economies of scale; (iii) market‐based approaches to scaling up of SLM, such as payment for ecosystem services and public–private partnerships, have a role to play, but cost–benefit analysis need to be better integrated into payment schemes; (iv) the economic benefits of carbon sequestration are too low to fund eco‐compensation schemes on their own but can provide supplementary funding; and (v) land degradation and SLM monitoring and assessment systems should be multiscale to support decision‐making on SLM and to monitor impact from the local to the national level. Copyright © 2014 Asian Development Bank  相似文献   
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Nixtamalization is the process of steeping dried corn in hot water with calcium hydroxide (lime) with subsequent removal of all or most of the pericarp through washing. The resulting product is called nixtamal. Approximately 60% of corn tortillas in Mexico are produced from nixtamal, with the remainder prepared from nixtamalized corn flour. Nixtamal was fortified with micronutrient premix containing iron, zinc, folic acid, niacin, riboflavin, and thiamin. Premix composition followed a proposed Mexican regulation for corn flour fortification, adjusted for moisture. Effects of premix on masa adhesiveness, hardness, and pH, as well as tortilla sensory properties, stretchability, rollability, and color were measured. Micronutrient levels were tested in the dry corn, nixtamal, masa, and tortillas. There were no significant differences in masa texture or pH, tortilla rollability, or consumer acceptance of tortillas when comparing unfortified control and fortified treatments. Added thiamin was almost entirely degraded during processing. Folic acid and riboflavin decreased 26 and 45%, respectively, through the masa‐tortilla manufacturing process. Niacin showed no significant loss. Despite processing losses, fortification resulted in significant nutrient increases compared with control tortillas. Folic acid increased 974%, riboflavin increased 300%, niacin increased 141%, iron increased 156%, and zinc increased 153% in fortified tortillas.  相似文献   
278.
The population of Calanus finmarchicus in the North Sea is replenished each spring by invasion from an overwintering stock located beyond the shelf edge. A combination of field observations, statistical analysis of Continuous Plankton Recorder (CPR) data, and particle tracking model simulations, was used to investigate the processes involved in the cross-shelf invasion. The results showed that the main source of overwintering animals entering the North Sea in the spring is at depths of greater than 600 m in the Faroe–Shetland Channel, where concentrations of up to 620 m−3 are found in association with the overflow of Norwegian Sea Deep Water (NSDW) across the Iceland–Scotland Ridge. The input of this water mass to the Faroe–Shetland Channel, and hence the supply of overwintering C. finmarchicus , has declined since the late 1960s due to changes in convective processes in the Greenland Sea. Beginning in February, animals start to emerge from the overwintering state and migrate to the surface waters, where their transport into the North Sea is mainly determined by the incidence of north-westerly winds that have declined since the 1960s. Together, these two factors explain a high proportion of the 30-year trends in spring abundance in the North Sea as measured by the CPR survey. Both the regional winds and the NSDW overflow are connected to the North Atlantic Oscillation Index (NAO), which is an atmospheric climate index, but with different time scales of response. Thus, interannual fluctuations in the NAO can cause immediate changes in the incidence of north-westerly winds without leading to corresponding changes in C. finmarchicus abundance in the North Sea, because the NSDW overflow responds over longer (decadal) time scales.  相似文献   
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