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961.
962.
Faecal nitrogen (FN) concentration is used as a marker for habitat quality and digestive efficiency in free‐ranging herbivores. In herbivores, FN can be separated into undigested plant N (analysed as the N concentration of the neutral detergent residue) and metabolic faecal N (MFN). It has been suggested that by differential analysis of the faecal fibre‐bound N, the MFN fraction can be further split into a bacterial N and an endogenous N fraction [Hesta et al., Br. J. Nutr. 90 (2003) 1007]. We applied these methods to 96 faecal samples of 48 mammalian herbivore species from zoos. Species were grouped into coprophageous and non‐coprophageous hindgut fermenters and ruminating and non‐ruminating foregut fermenters. Diet was not controlled. The FN decreased with body mass, possibly reflecting higher proportions of concentrates in diets of smaller animals. The proportion of MFN increased with FN, indicating that higher quality food might enhance the gastrointestinal bacterial flora. The only outlier to this pattern was the lesser panda (Ailurus fulgens), confirming the low relevance of fermentative digestion in this herbivorous ‘carnivore’. No relevant differences between the four digestion types were noted. The proportion of endogenous faecal N (32–80% of FN) was always higher than that of bacterial faecal N (7–30%), which contradicts basal understanding of herbivore digestive physiology. Thus, the method of Hesta et al. (2003) does not appear applicable to herbivores. While the results do not exclude the possibility that detailed differences might occur between digestion types, they indicate a high degree of similarity between herbivores that rely on bacterial fermentation, regardless of their digestion type, with respect to metabolic faecal losses.  相似文献   
963.
Reasons for performing study: Type 2 diabetes mellitus (T2DM) is diagnosed rarely in equine practice although it may be under‐recognised. A greater awareness of the condition and therapeutic considerations would be to the benefit of such cases presenting in practice. More investigation into the pharmacological management of these cases is needed. Objectives: Three cases of diabetes mellitus were investigated using a specific test for insulin sensitivity and pancreatic β cell function in order to define accurately and characterise the existence of T2DM in all 3 subjects. Methods: The insulin‐modified frequently sampled i.v. glucose tolerance test was performed in each case and the data so obtained were subject to minimal model analysis of insulin‐glucose dynamics. Cases were then monitored following treatment using a combination of dietary modification, metformin, glibenclamide and pergolide. Results: Marked insulin resistance was identified in each case and, furthermore, severe pancreatic β cell dysfunction was present therefore classifying each case as end stage T2DM. Treatment was nevertheless associated with restoration of normoglycaemia in all cases. Conclusions: T2DM in horses may be more common than generally considered. In some cases individuals may respond to therapy aimed at restoring insulin sensitivity and pancreatic function. Drugs used in other species for the treatment of T2DM have not yet been adequately tested in horses. Potential relevance: T2DM should be considered as an important differential diagnosis in mature to elderly horses and ponies suffering from weight loss, polydipsia and polyuria. Clinicians should be encouraged to offer treatment and management advice when such cases are encountered.  相似文献   
964.
This report describes a successful surgical repair of medial patellar luxation in a Miniature Shetland pony where manual reduction of the patella was not possible. The surgical procedure involves transection of the medial femoropatellar ligament to facilitate patellar release, the placement of a prosthetic suture to replace the lateral femoropatellar ligament and reinforcement of the lateral retinaculum by the use of a mesh implant. This is a newly described surgical technique for the rare but recognised condition of a medial luxation of the patella.  相似文献   
965.
A survey of veterinary technicians identified that needlestick injuries are very common, with 210/226 (93%) technicians reporting at least one needlestick injury over the course of their career. One hundred sixty-seven (74%) had experienced a needlestick injury during the preceding year. Exposure to animal blood and various drugs was common. It was particularly concerning that needlestick injuries involving chemotherapeutic agents and prostaglandin were reported. Eight (3.5%) technicians had required medical care for a needlestick injury and 2 (0.8%) had lost time at work. The approach to sharps handling and needlestick injury avoidance was poor and most needlestick injuries had not been reported to employers. Measures need to be undertaken to improve sharps handling practices to reduce the number of needlestick injuries among veterinary technicians.  相似文献   
966.
One constraint that range scientists must face in grazing studies is the lack of accurate and repeatable techniques for discriminating grazing effects from both temporal variability and spatial heterogeneity of vegetation. Both forms of variability contribute to inconsistent grazing system effects on vegetation response and forage production in semiarid ecosystems. Remote sensing may be an efficient tool for detecting differences in spatial and temporal patterns of grazing impact on vegetation. The purpose of this study was to evaluate the spectral data derived from satellite images as a tool for comparing grazing system impacts on spatial and temporal vegetation patterns. We evaluated the effect of two grazing systems, “Continuous” (C) and “Two-Paddocks Rest-Rotation” (TPRR), on vegetation cover from 1996 to 2006 in a semiarid ecosystem of Argentina. We compared grazing effects on vegetation cover using two indices derived from the Normalized Difference of Vegetation Index (NDVI) data from Landsat Thematic Mapper images. We observed a slight advantage in NDVI improvement for the TPRR over the C. Even though, in both grazing systems, an upward vegetation trend occurred only in areas located far from the watering points, TPRR showed higher relative vegetation cover near the watering point than C. We consider this methodology an important step for monitoring vegetation changes and making management decisions in livestock systems of semiarid regions because grazing system impacts may be compared for both spatial and temporal vegetation patterns. However, we think that the key next step is to develop procedures that discriminate between forage and nonforage components.  相似文献   
967.
1. The aim of this study was to evaluate the ability of frozen-thawed testicular cells transplanted into infertile cocks to restore spermatogenesis and to compare two cryoprotectants (CPA) (dimethylsulfoxide (DMSO) and Biofreeze).

2. A total of 24 infertile White Leghorn (WL) cocks were transplanted with cryopreserved testicular cells from fertile adult donor cocks. Both genetically close and phylogenetically distant chicken breeds were used as donor cocks.

3. Twelve out of 24 WL recipient cocks with cryopreserved testicular cells restored spermatogenesis within 2 months after the transplantation. Six out of 12 recipient cocks with restored spermatogenesis successfully produced progeny expressing the donor phenotype.

4. There was no difference between the CPA in cell viability after thawing or in the number of offspring produced from cryopreserved testicular tissue.

5. The present work represents the first report of production of a donor-derived healthy progeny following frozen-thawed testicular cell transplantation in adult birds. The described results may contribute to preservation of endangered avian species and to maintaining their genetic variability.  相似文献   

968.
The onset of ossification centres of the pelvic girdle and leg skeleton of the quail in embryos and juvenile birds were studied. Specimens, which were cleared and were stained with Alcian Blue and Alizarin Red S, were examined at the stereomicroscope. The ilium and the pubis began to ossify at the 8th day (E8), whereas the ischium at E9. Perichondral ossification was observed at E6 in the femur, tibia and fibula. A secondary ossification centre was detected in the proximal epiphysis of the tibiotarsus at the 15th post‐hatching day (P15). The patella began to ossify at P30. Regarding the tarsal bones tibiale, pre‐tibiale and fibulare, ossification was observed at the E15, E12 and E16, respectively. The metatarsals II, III, IV ossified at E7, whereas the metatarsal I at E11. The centres of ossification of the 1st phalanges of all digits were observed at E9. At the same day, the ossification centres of the 2nd phalanx of digits II and III as well as the 3rd phalanx of digit III appeared. At E10, ossification was observed in the 2nd phalanx of digit I, in the 3rd phalanx of digit II and in the 2nd and 3rd phalanx of digit IV. In the 4th phalanx of digit III and in the terminal phalanges of digit IV, ossification was observed at E11. The data presented here provide useful baseline information on the normal sequential pattern of ossification in the pelvic girdle and leg skeleton in this species.  相似文献   
969.
970.
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