Mixtures of steroidal sapogenins isolated from the seed and combined aerial parts (foliage) of fenugreek (cultivar Amber) have been examined by capillary column gas chromatography with mass spectral and flame ionization detectors. Diosgenin [(25R)-spirost-5-en-3β-ol] was the major component in seed and foliage extracts hydrolyzed with hydrochloric acid. Yamogenin also appeared to be present. Tigogenin, neotigogenin, smilagenin, and sarsasapogenin were identified in the extracts. Dihydroxy steroidal sapogenins, tentatively identified as yuccagenin, gitogenin, and neogitogenin, were detected as minor components in hydrolyzed extracts from seed. A gas chromatographic method based on the use of an internal standard and a column of HP-5MS was developed to determine diosgenin in Amber fenugreek. Expressed on a dry weight basis, mean levels of diosgenin in seed were 0.54%. In field-grown foliage sampled during a season at 9, 15, and 19 weeks postseeding, diosgenin levels were 0.16, 0.07, and 0.07%, respectively. Keywords: Steroidal sapogenins; spirostanols; fenugreek; diosgenin; quantitation; seed; foliage

The effects of weaning and transport on fecal shedding of Escherichia coli and on E. coli O157:H7 were investigated using 80 Angus and 94 Charolais range steer calves blocked by breed and assigned to four treatments. The calves were or were not preconditioned before transport on commercial cattle liner to the feedlot via long (15 h) or short (3 h) hauling duration, yielding preconditioned long haul (P-L; n = 44), preconditioned short haul (P-S; n = 44), nonpreconditioned long haul (NP-L; n = 43), and nonpreconditioned short haul (NP-S; n = 43). Preconditioned calves were vaccinated and weaned 29 and 13 days, respectively, before transport. Nonpreconditioned calves were weaned 1 day before long or short hauling, penned for 24 h and hauled again for 2 h, and vaccinated on arrival at the feedlot. Fecal samples were collected from calves while on pasture, at weaning, at loading for transport, on arrival at the feedlot, twice in the first week, and on days 7, 14, 21, and 28 for enumeration of total E. coli (biotype 1) and detection of E. coli O157:H7. No calves were positive for E. coli O157:H7 before transport. Following transport, more (P < 0.005) NP-L calves (6 of 43) tested positive for E. coli O157:H7 than did P-L (1 of 44), NP-S (1 of 43), or P-S (0 of 44) calves, and on days 0, 1, 7, and 21, their levels of shedding of E. coli were higher (P < 0.005). The calves' susceptibility to infection from the environment (possibly the holding facilities or feedlot pens) was likely elevated by the stresses of weaning, transport, and relocation. Lack of preconditioning and long periods of transport (NP-L) increased fecal shedding of E. coli and E. coli O157:H7. Preconditioning may serve to reduce E. coli O157:H7 shedding by range calves on arrival at the feedlot.

. 1997. Cortisol and ␤-endorphin responses to physical and psychological stressors in lambs. Can. J. Anim. Sci. 77: 689-694. Plasma cortisol, β-endorphin, T3 and T4 were determined in lambs before, during and after exposure to stress in order to evaluate the potential use of these hormones to objectively measure stress responses. Lambs were exposed to tail-docking, castration, weaning, isolation, and restraint stress. Twelve ewe and 24 ram lambs were assigned to the experiment, with 12 of the ram lambs surgically castrated when 3-wk old. Tail docking within 24 h of birth did not (P > 0.05) elevate either plasma cortisol or β-endorphin. Castration markedly elevated (P < 0.001) plasma cortisol and β-endorphin within 15 min of surgery. Both hormones were highly elevated for the first 4 h . Plasma cortisol returned to control levels by 24 h whereas β-endorphin was still elevated (P < 0.05) 24 h after castration. Plasma cortisol levels were elevated for the first 60 min following weaning (P < 0.005) and again at 24 h after dam removal (P < 0.001). Plasma β-endorphin was not elevated (P > 0.05) any time during the 72 h following weaning. Plasma cortisol (P < 0.001) and β-endorphin (P < 0.05) were elevated during the first 60 min following the start of 1 h of isolation. Results were similar for partial and total isolation. No effects of isolation were found for the next 23 h. Plasma cortisol (P < 0.005) was elevated during the first 30 min following 4 min of shearing-like restraint, whereas plasma β-endorphin was elevated only at 7 min (P < 0.05) after restraint began. No further effects of restraint were found prior to termination of sample collection at 24 h. None of the stressors employed affected plasma concentrations of T3 and T4. This study has shown that measurements of plasma cortisol and β-endorphin in blood samples obtained before, during and after stress are useful in assessing stress in lambs. The painful stressor, castration, induced marked and prolonged elevations of both hormones, whereas psychological stressors elicited graded, short-term cortisol responses and limited β-endorphin responses.Key words: Cortisol, β-endorphin, physical stress, psychological stress, lambs Mears, G. J. et Brown, F. A. 1997. Réponse du cortisol et de la ␤-endorphine aux stressants physiques et psychologiques chez les agneaux. Can. J. Anim. Sci. 77: 689-694. Nous avons suivi les niveaux plasmatiques de cortisol, de β-endorphine, de T3 et de T4 chez les agneaux avant, pendant et après une exposition aux stress afin d'évaluer les possibilités d'utilisation de ces hormones comme mesure objective des réponses au stress. Des agneaux étaient exposés à la caudectomie, à la castration, au sevrage, à l'isolement et à la contention. Douze agneaux femelles et 24 agneaux mâles étaient utilisés, dont 12 agneaux mâles étaient castrés par voie chirurgicale à l'âge de 3 semaines. La caudectomie réalisée dans les 24 heures suivant la naissance ne causait pas de relèvement (P > 0,05) des niveaux plasmatiques de cortisol ou de β-endorphine. En r...

No abstract

.Comparison of alfalfa and fenugreek (Trigonella foenum-graecum) silages supplemented with barley grain on performance of growing steers. Can. J. Anim. Sci. 78: 343-349. To compare nutritive value of alfalfa and fenugreek silages for weaned backgrounding feedlot steers, isonitrogenous diets of alfalfa or fenugreek silage, supplemented with three levels of steam-rolled barley (0, 15 and 30% DM) were fed ad libitum to 60 steers (initial weight of 237 ± 18 kg). The study was conducted in individual pens for 105 d using a 2 × 3 factorial experiment. Fenugreek was cut 17 wk after seeding while the alfalfa was cut at mid-bloom. Both fenugreek and alfalfa silages were prepared in plastic tube silos after wilting to 38 and 35% DM, respectively. After ensiling for 40 d, silage tubes were opened and a feeding trial was conducted. Alfalfa and fenugreek silage contained similar levels of CP (18.0 and 17.2 %, respectively) while fenugreek silage contained a lower level of NDF (38.2%) than alfalfa silage (40.4%). Dry matter intake (DMI) and average daily gain (ADG) of steers increased (P < 0.001) and feed efficiency (FE) improved linearly (P < 0.001) with increasing grain level in the diet. Dry matter intake (6.4 vs. 6.2 kg d -1 ), ADG (0.82 vs. 0.84 kg d -1 ), FE (8.1 vs. 7.8 ), total rumen volatile fatty acids (103.4 vs. 105.3 mM), rumen fluid pH (6.9 vs. 6.9) and rumen ammonia concentration (9.6 vs. 10.4 mg dL -1 ) in steers were similar for both alfalfa-and fenugreek-silage-based diets, respectively. Although in vitro rate of gas production was different at 12.6 and 17.4% h -1 for alfalfa and fenugreek diets, respectively, potential gas production at the end of 72 h of fermentation was similar (21.6 vs. 22.3 mL 100 mg -1 DM). The presence of steroidal saponins in fenugreek plants did not affect steer performance or hormonal status when fed as silage. Results from this study indicate that the nutritive value of fenugreek silage is comparable to that of mid-bloom alfalfa silage, and that fenugreek, a high-DM yielding annual legume, has potential to be a valuable forage in feedlot diets. Les ensilages des deux fourrages étaient confectionnés en tubes de plastique, après réduction respective de taux de m.s. à 38 et à 35 %. Quarante jours après la mise en silo, les tubes étaient ouverts et les ensilages utilisés pour un essai d'alimentation. Les deux ensilages avaient la même teneur en protéine brute, soit 18 pour la luzerne et 17,2 % pour le fenougrec, mais l'ensilage de fenou grec contenait moins de FDN (38,2 %) que celui de luzerne (40,4 %). L'accroissement ppde la proportion de grain dans la ration entraînait une amélioration linéaire statistiquement significative (P < 0,01) de l'ingéré de m.s. (IMS), du GMQ et de l'efficacité alimentaire (EA). La IMS, le GMQ, la EA, la teneur en acides gras volatils dans le rumen, le pH du liquide ruminal et la concentration ruminale d'ammoniac étaient essentiellement identiques dans les deux types d'ensilage. Bien que le taux de fermentation in vitro variait selon le régime, soit 12,6 % ...