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91.
This study evaluated the association between plasma anti-Mullerian hormone (AMH) concentration and fertility in Nelore (Bos indicus) heifers submitted to timed artificial insemination (TAI). At the onset of the synchronization protocol, heifers (n = 289) received a subcutaneous P4 ear implant (3 mg) and 2 mg of oestradiol benzoate. Eight days later, the P4 implant was removed and 0.5 mg of oestradiol cypionate, prostaglandin (0.265 mg, i.m.) and equine chorionic gonadotropin (300 UI, i.m.) was administered, and TAI was performed 48 hr after ear implant removal. Ovarian ultrasound evaluations were performed to measure number of ovarian follicles, dominant follicle size and ovulation response. Pregnancy diagnosis was performed by ultrasound 30 days after AI. Heifers with greater circulating AMH had more antral follicles, a smaller dominant follicle near timed ovulation and lower ovulation response to the timed AI protocol compared to heifers with lower circulating AMH. Although AMH and pregnancy outcome had a quadratic-shaped pattern, AMH was not significantly associated with fertility. In conclusion, heifers with lower AMH had larger follicles towards the end of the synchronization protocol and greater ovulation responses, whereas greater circulating AMH was unrelated to conception success.  相似文献   
92.

Background

Since transport evokes physiological adjustments that include endocrine responses, the objective of this study was to examine the responses of circulating β-endorphin, adrenocorticotrophic hormone (ACTH) and cortisol levels to transport stress in stallions.

Methods

Forty-two healthy Thoroughbred and crossbred stallions were studied before and after road transport over distances of 100, 200 and 300 km. Blood samples were collected from the jugular vein: first in a single box immediately before loading (pre-samples), then immediately after transport and unloading on arrival at the breeding stations (post-samples).

Results

An increase in circulating β-endorphin levels after transport of 100 km (P < 0.01), compared to basal values was observed. Circulating ACTH levels showed significant increases after transport of 100 km (P < 0.001) and 200 km (P < 0.001). Circulating cortisol levels showed significant increases after road transport over distances of 100, 200 and 300 km (P < 0.001). An effect of transport on β-endorphin, ACTH and cortisol variations was therefore evident for the different distances studied. No significant differences (P > 0.05) between horses of different ages and different breeds were observed for β-endorphin, ACTH and cortisol levels.

Conclusion

The results obtained for short term transportation of stallions showed a very strong reaction of the adrenocortical system. The lack of response of β-endorphin after transport of 200–300 km and of ACTH after transport of 300 km seems to suggest a soothing effect of negative feedback of ACTH and cortisol levels.  相似文献   
93.
The aim of the present study was to determine the relationship among body weight (BW), body condition score (BCS) and rump fat thickness (RFAT) measured by ultrasonography, and validate the relationship between BCS and RFAT over the time. Two hundred sixty and six Nelore cows had their BW, BCS and RFAT evaluated at five different moments during the production cycle: M1) weaning; M2) parturition, M3) 42 days post-partum; M4) 82 days post-partum and M5) 112 days post-partum. A BCS value was attributed for each cow following a 1 to 5 points scale. Ultrasonographic images for RFAT measurement were obtained using a 3.5 MHz linear transducer. Images were immediately analyzed as soon as they were formed and frozen. Body condition scores and ultrasound measurements were collected on the same day by a single trained technician. The relationship between BCS and RFAT values was investigated by regression models. The analysis of similarity among the five obtained models was performed using the proc MIXED from SAS and the correlations among variables were analyzed with proc CORR from SAS. The BCS was able to predict RFAT in Nelore cows in all different moments evaluated. Also, it was shown that BCS presented high correlation (r = 0.82 to 0.93) and relationship (R2 = 0.73 to 0.92) with RFAT. However, both BCS and RFAT showed low correlation (r = 0.37 to 0.50) and relationship (R2 = 0.13 to 0.25) with BW. The BCS classification by visual method using a 1 to 5 point scale, was able to predict the RFAT in Nelore cows over the time.  相似文献   
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95.
Summary Exploration and collection of plant genetic resources were continued in central Italy 1989—regions Abruzzo, Umbria, Marche, Toscana.Triticum dicoccon was used as an indicator for traditional agriculture. 169 accessions were collected, mainly of cereals, vegetables and grain legumes. Worth mentioning are land-races ofTriticum aestivum, T. durum, Secale cereale, Pisum sativum, Lactuca sativa andCucurbita maxima. Brassica oleracea var.palmifolia, the palm-leaved kale, is an important vegetable in the Toscana. Several other rare crops could be also collected.
Sammlung pflanzlicher genetischer Ressourcen in Italien 1989
Zusammenfassung Die Exploration und Sammlung pflanzlicher genetischer Ressourcen wurden 1989 in Mittelitalien fortgesetzt — Regionen Abruzzo, Umbria, Marche, Toscana.Triticum dicoccon wurde als Indikator für traditionelle Landwirtschaft verwendet. 169 Proben wurden gesammelt, hauptsächlich von Getreiden, Gemüsen und Körnerleguminosen. Erwähnenswert sind Landsorten vonTriticum aestivum, T. durum, Secale cereale, Pisum sativum undCucurbita maxima. Brassica oleracea var.palmifolia, der Palmkohl, ist ein wichtiges Gemüse in der Toscana. Verschiedene andere seltene Fruchtarten konnten ebenfalls gesammelt werden.

1989
1989 , , , .Triticum dicoccon . 169 , , . Triticum aestivum, T. durum, Secale cereale, Pisum sativum Cucurbita maxima. Brassica oleracea var.palmifolia, , . .
  相似文献   
96.
Physical and chemical properties and the total content of potentially toxic metals (PTMs) in waters and soils were studied from the High Moulouya Valley (Morocco) in order to assess the impact of the past mining activity on their quality and to lay the foundations of a potential reclamation of the area. Surface water and groundwater samples were collected from the Moulouya River and mine pit lakes; tailings and soils were sampled inside and outside the mine sites of Zeïda, Mibladen, and Aouli. Both waters and soils were alkaline, due to the limestone environment, and contained Pb and Zn as main metallic contaminants. Pollution levels were highest within the Mibladen mining site, and soil pollution was mainly restricted to the areas where activities of metal concentration were carried out. Tailings and soils from these areas besides Pb and Zn were also polluted by As, Cd, and Cu showing clay fraction highly enriched in metal contaminants. At the time of study, all soils and wastes (including the highly polluted tailings) were in advanced stage of spontaneous herbaceous and arbustive revegetation. It is concluded that, in the High Moulouya Valley, the processes governing PTM transfer from the element-rich sites to the nearby environment are strongly influenced by pH, carbonate content, and semi-arid climate reducing metal mobility from the mining waste impoundments by dissolution. The transfer by wind and water erosion of metal-enriched fine waste particles is likely to be a much more important vector for metal dispersion. In this perspective, among a range of land remediation techniques available, natural and oriented revegetation could represent a low-cost and possible permanent solution.  相似文献   
97.
98.
99.
A total of 12 fatty acid esters of Z- and E-p-coumaryl alcohol were isolated from cv. Annurca apple fruit and characterized. This apple variety is widely cultivated in the south of Italy, and the fruits typically undergoe a reddening treatment after harvest. Structures of the p-coumaryl esters were elucidated by GC-MS and (1)H and (13)C NMR after purification of individual compounds by HPLC. It was found that the esters are localized in the fruit peel. During reddening of the fruit, there was a substantial increase in the amount of esters and particularly in molecular species with unsaturated fatty acids. The individual compounds were tested for antioxidant activity, and over half were shown to be at least as effective as alpha-tocopherol.  相似文献   
100.
The winding process leading to the formation of rolled-up spermatozoa in Collembola is described. It is a phenomenon common to all collembolan species examined so far and it starts with the organization of a cytoplasmic flattened evagination beneath the head of the elongated spermatid, which gives rise to an extracellular cavity. Within this cavity secretory material produced by the epithelial cells of testes is progressively stored. The spermatozoon, whose cytoplasm is reduced to a thin layer, enrolls around this material. The final appearance is that of a spheroidal or lenticular structure containing dense material in the central extracellular cavity; this cavity is surrounded by the flattened sperm in whose cytoplasm the sperm components forms several spires. The material into the extracellular cavity becomes progressively denser and has a different appearance in the species examined.  相似文献   
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