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131.
The non-haem iron concentration was estimated in post-mortem liver samples from 51 horses (age range 1–25 years). Two were normal and 49 had been suffering from conditions that were not expected to have had long-term effects on iron metabolism. Muscle samples (splenius and biceps femoris) from 23 of these horses were also analysed. There was a highly significant age-related increase in the non-haem iron concentration in the liver (r=0.635,p<0.001), but not in the muscles, in which the iron concentration was much lower than in the liver.Abbreviations A(535) absorbance at 535 nm - Asc ascorbic acid - BPS bathophenanthroline sulphonate, sodium salt - NaAc sodium acetate - TCA trichloracetic acid - TIBC total iron-binding capacity Dr W.N.M. Ramsay, BSc, PhD: It is deeply regretted that Dr Ramsay died following the preparation of this paper. All correspondence and requests for reprints should be sent to Professor M.M.H. Sewell at the above address.  相似文献   
132.
Reptiles are well-known sources of human Salmonella infections; however, little is known about the ability of Salmonella to cause disease in reptiles. Thirty-seven isolates of Salmonella enterica subspecies arizonae (S. arizonae) were obtained from retrospective and prospective studies of a closed colony of ridgenose rattlesnakes (Crotalus willardi) with osteomyelitis. All isolates (N = 7) from bone lesions were of a single serotype, 56:z4,z23, and this serotype was found on only 1 occasion among 8 other serotypes isolated from 21 cloacal and intestinal samples. The remainder (N = 7) of serotype 56:z4,z23 isolates were from other extraintestinal sites, including liver, ovary, blood, and testis. S. arizonae isolates were susceptible to most antimicrobials, and plasmid profiles did not correlate with serotype or antimicrobial resistance. Isolates of the 56:z4,z23 serotype (N = 14) formed a tight cluster with 95% similarity by XbaI macrorestriction analysis. Individual isolates of serotypes, 56:z4,z23, 38:(k)-z35, and 48:i-z invaded HeLa cells but an isolate of serotype 50:r-z did not. The same individual isolates of serotype 56:z4,z23 and 48:i-z also invaded viper heart cells. The Salmonella InvA gene was detected by polymerase chain reaction (PCR) in all S. arizonae serotypes tested, including 5 serotype 56:z4,z23 isolates and individual isolates of serotypes 48:i-z and 50:r-z. A source or possible explanation for increased virulence of S. arizonae serotype 56:z4,z23 in this unique host has not been found.  相似文献   
133.
Background: Recent increases in intra-litter variability in weaning weight have raised swine production costs. A contributor to this variability is the normal birth weight pig that grows at a slower rate than littermates of similar birth weight. The goal of this study was to interrogate biochemical profiles manifested in skeletal muscle originating from slow growing(SG) and faster growing littermates(control), with the aim of identifying differences in metabolic pathway utilization between skeletal muscle of the SG pig relative to its littermates. Samples of longissimus muscle from littermate pairs of pigs were collected at 21 d of age for metabolomic analysis.Results: Birth weights did not differ between littermate pairs of SG and Control pigs(P 0.05). Weaning weights differed by 1.51 ± 0.19 kg(P 0.001). Random forest(RF) analysis was effective at segregating the metabolome of muscle samples by growth rate, resulting in a predictive accuracy of 81% versus random segregation(50%).Decreases in sugars in the pentose phosphate pathway(PPP) in the longissimus of SG pigs were detected(P 0.05). Decreases were also apparent in glycolytic intermediates(glycerol-3-phosphate and lactate) and key glycolysis-derived intermediates(glucose-6-phosphate and fructose-6-phosphate; P 0.05). SG pigs had increased levels of phospholipids, lysolipids, diacylglycerols, and sphingolipids(P 0.05). Pathway analysis identified a cluster of molecules associated with muscle and collagen/extracellular matrix breakdown that are increased in the SG pig(glutamate, 3-methylhistidine and hydroxylated proline moieties; P 0.05). Nicotinate metabolism was altered in SG pigs, resulting in a 78% decrease in the nicotinamide adenine dinucleotide pool(P 0.05).Conclusions: These metabolomic data provide the first evidence for biochemical mechanisms that should be investigated to determine if they have a potential role in the slow growth in some normal birth weight piglets that contribute to increased intra-litter variability in weaning weights and provides essential information and potential targets for the development of nutritional intervention strategies.  相似文献   
134.
135.
Steatitis due to vitamin E deficiency occurred in three 10-wk-old boat-billed herons (Cochlearius cochlearius) despite daily placement of a powdered vitamin supplement on the fish that was subsequently washed off by the parents. Physical findings included emaciation, yellow-brown subcutaneous nodules, a firm distended coelom, stomatitis, and yellow-white, submucosal pharyngeal nodules. Clinical pathology revealed heterophilic leukocytosis, anemia, hypoproteinemia, and low plasma alpha (alpha)-tocopherol levels (1.94 microg/ml and 2.14 microg/ml). Two of the chicks died of severe, diffuse pansteatitis and respiratory aspergillosis.  相似文献   
136.
Five chimpanzees (Pan troglodytes) initially received oral droperidol sedation (1.25 mg for a juvenile chimpanzee, body wt = 18.5 kg, and 2.5 mg for adults, body wt >20 kg, range: 18.5-71 kg) followed by transmucosal carfentanil administration at 2.0 microg/kg. This preinduction regimen was developed to produce heavy sedation or even light anesthesia in order to eliminate the need for or at least minimize the stress of darting with tiletamine/zolazepam at 3 mg/kg i.m. This study was designed to assess the safety and efficacy of transmucosal carfentanil. Once each animal was unresponsive to external stimuli, or at approximately 25 min (range 24-34 min) after carfentanil administration, naltrexone and tiletamine/zolazepam (N/T/Z) were combined into one intramuscular injection for anesthetic induction. Naltrexone was administered at 100 times the carfentanil dose in milligrams. For comparison, two chimpanzees received only droperidol, 2.5 mg p.o., followed by tiletamine/zolazepam, 3 mg/kg i.m. The preinduction period for all animals receiving carfentanil was characterized as smooth, with chimpanzees becoming gradually less active and less responsive to external stimuli. Two animals became very heavily sedated at 24 and 35 min, respectively, and were hand injected with N/T/Z. The other three chimpanzees became sternally recumbent but retained some response to stimuli, and N/T/Z was administered by remote injection with minimal response. Rectal body temperatures, pulse and respiratory rates, arterial oxygen hemoglobin saturation, and arterial blood gases were measured at initial contact (t = 0 min) and at 10-min intervals thereafter. Respiratory depression was present in all chimpanzees, regardless of protocol. Mean hemoglobin saturation was 91% for both groups. Mean partial pressure of oxygen, arterial values for carfentanil-treated and control animals were 64.4 +/- 7.6 and 63.5 +/- 6.0 at t = 0, respectively. Only the partial pressure of carbon dioxide, arterial (Paco2) and pH showed significant differences between treated and control animals. Mean Paco2 was greater and mean pH lower for the carfentanil-treated group compared with the controls at t = 0 (58.9 +/- 3.7 and 50.3 +/- 3.1 for Paco2 and 7.33 +/- 0.02 and 7.40 +/- 0.30 for pH, respectively). The results of this study suggest that oral droperidol followed by transmucosal carfentanil can be used effectively as a premedication regimen to produce profound sedation, which limits the stress of darting during parenteral anesthetic induction with tiletamine/zolazepam in chimpanzees. The main side effect of respiratory depression appears to be adequately managed by reversing the carfentanil at the time of induction.  相似文献   
137.
Laboratory studies show that the reaction of short-lived O2(B3Sigmau) molecules (lifetime approximately 10 picoseconds) with N2 and the photodissociation of the N2:O2 dimer produce NOx in the stratosphere at a rate comparable to the oxidation of N2O by O(1D). This finding implies the existence of unidentified NOX sinks in the stratosphere. The NO2 observed in this experiment is isotopically heavy with a large 15N/14N enhancement. However, photodissociation of this NO2 unexpectedly produced NO molecules with a low 15N/14N ratio. The diurnal odd-nitrogen cycle in the stratosphere will be marked by a complex isotope signature that will be imprinted on the halogen and HOX catalytic cycles.  相似文献   
138.
139.

Background

Pine bark is a rich source of phytochemical compounds including tannins, phenolic acids, anthocyanins, and fatty acids. These phytochemicals have potential to significantly impact on animal health and animal production. The goal of this work is to measure the effects of tannins in ground pine bark as a partial feed replacement on feed intake, dietary apparent digestibility, nitrogen balance, and mineral retention in meat goats.

Results

Eighteen Kiko cross goats (initial BW = 31.8 ± 1.49 kg) were randomly assigned to three treatment groups (n = 6). Dietary treatments were tested: control (0 % pine bark powder (PB) and 30 % wheat straw (WS)); 15 % PB and 15 % WS, and 30 % PB and 0 % WS. Although dry matter (DM) intake and digestibility were not affected (P > 0.10) by feeding PB, neutral detergent fiber (linear; P = 0.01), acid detergent fiber (linear; P = 0.001) and lignin digestibility (linear; P = 0.01) decreased, and crude protein (CP) digestibility tended to decrease (P = 0.09) as PB increased in the diet, apparent retention of Ca (P = 0.09), P (P = 0.03), Mg (P = 0.01), Mn (P = 0.01), Zn (P = 0.01) and Fe (P = 0.09) also increased linearly. Nitrogen intake and fecal N excretion were not affected (P > 0.05) by addition of PB in the diet, but N balance in the body was quadratically increased (P < 0.01) in the 15 % PB diet compared to other diets. This may be due to more rumen escape protein and less excreted N in the urine with the 15 % PB diet. The study showed that a moderate level of tannin-containing pine bark supplementation could improve gastrointestinal nitrogen balance with the aim of improving animal performance.

Conclusion

These results suggest that tannin-containing PB has negative impact on fiber, lignin, and protein digestibility, but positively impacted on N-balance.  相似文献   
140.
The Commonwealth Potato Collection contains 77 species following the incorporation of the personal collection of Professor JG Hawkes. The material originates from several expeditions to the Americas and represents a potentially valuable source of resistance to pests and pathogens, including potato cyst nematodes (PCN). The germplasm from the Hawkes collection screened in this study included taxa mainly from Mexico, Bolivia, Argentina and Peru. Seedlings of 198 accessions, from 63 different species were screened for reaction to the PCN species G. pallida and G. rostochiensis. Of the 198 accessions tested, 56% contained G. pallida-resistant clones and 53% contained clones resistant to G. rostochiensis. Twelve species in this survey are believed to contain novel, previously unreported sources of resistance. The geographical distribution of resistance indicated a contrast between the two PCN species. Although, as in previous studies, resistance to G. rostochiensis was centred on Bolivia and Argentina, G. pallida resistance was found across the geographical range of tuber-bearing Solanum. The possibility of cross-resistance arising from selective pressure from the more northern species G. mexicana is discussed. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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