The effects of different irrigation regimes on yield and silage quality of corn under semi-arid conditions

The aim of this study was to evaluate the effects of different quantities of drip irrigation water on the corn yield and silage quality under semi-arid conditions. The seasonal evapotranspiration (ETc) for the different irrigation regimes varied from 434 to 947 mm in 2004 and from 468 to 1003 mm in 2005 for total irrigation periods of 108 and 113 days, respectively. Combining data from both years, the relative evapotranspiration deficit (1−ETa/ETm) for different regimes was 19 to 54% in corn compared to the maximum seasonal ETc when water was not limited in the (I100) regime. During the course of both years, irrigation had an apparent effect on the total fresh silage yield (FSY), with yields increasing steadily from water stress to fully irrigated conditions, while silage yields increased linearly with the total depth of irrigation water applied between planting and harvest. Combining data from both years showed that the FSY was 35.0, 53.6, 83.3 and 88.9 t ha-1 for I25, I50, I75 and I100, respectively. Moreover, the largest FSY recorded amongst these experiments at maximum seasonal yield in single treatment was 89.1 t ha-1 in 2004 and 88.7 t ha-1 in 2005. The water content decreased considerably in all but FSY, while the dry matters yield (DMY), organic matter (OM), acid detergent fiber yield (ADFY) and in vitro dry matter digestibility (IVDMD) increased. Furthermore, the study substantiated that the highest yield and silage quality were obtained at the full (I100) irrigation regime.Key words: Silage, deficit irrigation, yield, silage quality

Frozen rumen fluid as microbial inoculum in the two-stage in vitro digestibility assay of ruminant feeds

Abstract This study was carried out to investigate the possibility of using frozen rumen fluid (RF) as an inoculum source in the determination the in vitro dry matter digestibility (IVDMD) of ruminant feeds. In the first experiment six roughages (barley straw, wheat straw, lentil straw, wheat silage, maize silage and lucerne hay) and six different compound feeds (two dairy cattle, two beef cattle, one ram lamb and one lamb finishing compound feeds) were chosen as test material. Two different types of cryoprotectants (5% glycerol vs. 5% dimethyl sulfoxide, DMSO) and two types of freezing methods (liquid nitrogen vs. deep freezing) were used to preserve the RF. Fresh RF was used as the control. In response to the results of the first experiment, a second experiment was conducted to establish if microbial digestibility could be improved by extending the duration of incubation of the roughages from 48 to 60, 72 or 96 h. When using the RF inoculum treated with 5% DMSO and frozen in liquid nitrogen, the IVDMD of the compound feeds were similar to those of the control. However, when the 5% DMSO treated inoculum was frozen in the deep freezer, some of the compound feeds had similar IVDMD values to the control but not all. Lower IVDMD values were recorded when glycerol was used as a cryoprotectant. In the case of the roughages the use of both freezing methods and cryoprotectants resulted in lower IVDMD values compared to the control. In the second experiment the increasing of the duration of incubation of roughages from 48 to 72 h improved their IVDMD to values similar to that of the control. This suggested that the length of the incubation of roughages should be 72 h instead of 48 h when using inocula treated with 5% DMSO as a cryoprotectant and frozen in a deep freezer. However, further research is required before frozen RF can be recommended as source of inoculum. _______________________________________________________________________________

Combined Phacoemulsification and Trabeculectomv Versus Trabeculectomy Alone: A Comparison Study Using Mitomycin C

Purpose The suigical management o] coexisting cataiael and glaucoma is contioveisial We compared patients \\ho underwent combined trabeculeciomv and phacoemulsification (PEM/TRAB) with trabeculeetomy alone(TRAB) to assess long-term intraocular pressure! IOP) control Methods We retrospectsely ievieued 42 eves m îS consécutive patients who underwent combined PHM/TRAB w ith milomycm C An aged-matched control group of 42 patients who underwent TRAB with mituim cm C during the same time period \x as randornU selected from 248 consecutn e patients All patients had a minimum of 12 months folio -up Results Mean preoperaiive IOP, and number of glaucoma médications were sinulai tin ihetn groups (22.S ±6 9 mm Hg vs 22 9 ±6 S mm Hg. 2 12 ±8 \s 2 26 ±1 medications combined ITMATRAH vs TRAB, respectively) Postoperative K \u3eP uas signiticanth louer at all follow-up intervals At final follow-up after a mean 21 S ±6 months, IOP a\ craped 13 V ±5 1 mm I Ig in the I\u27FM/TRAIi group and 12 3 ±47 mm Hg in the TRAB group Bleb sun ival was excellent m holh groups, although slightly higher m the TRAB grour.(37/42 PKM/TRAH vs 41/42 TRAJI) Both groups required significantly fewer glaucoma medications at final follow-up( 3b± 6 vs 5 ± X TRAB/PHM vs TRAB) Complications were relatively minor and similar between the two groups Conclusions. The success rates for combined PliM/TRAB using small incisions and limhus-based conjunctival Haps appear to approach those of TRAB alone