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101.
Summary The potential for increased productivity of N'Dama cattle in response to small supplementary inputs of proteinaceous by-products has been shown to be substantial under village husbandry conditions in The Gambia. Young N'Dama bulls were used to compare sesame cake with cottonseed as sources of supplementary protein during the wet and early dry seasons of 1987. They were fed 0, 40, 80 or 160 g crude protein/day in these forms for four months. Supplementation significantly increased growth rate from 169 g/d in controls to means of 272 and 271 g/d for those given sesame cake and cottonseed respectively; there were no significant differences among the supplemented groups. During the four months of the dry season immediately after supplementation ceased all previously supplemented groups grew significantly more rapidly than the controls (at leastP<0·05), indicating a substantial carry over effect of the supplements. Over this period the mean gain of the groups previously given sesame cake exceeded that of those that had received cottonseed (217 cf. 158 g/d;P<0·01). The economic benefits of these responses were substantial.
Comparacion de torta de sesamo y de semilla de algodon como fuente suplementaria de proteina para terneros destetos N'Dama en Gambia
Resumen Se ha demonstrado el potencial para incrementar la productividad del ganado N'Dama, como resquesta a peque?as cantidades de insumos suplementarios de proteína, bajo condiciones de villorrio en Gambia. Se utilizaron terneros destetos N'Dama par comparar la torta de sésamo y de semilla de algodón como fuente de proteína suplementaria durate la estaicón lluviosa y principio de la seca del a?o 1987. Se les dió a los animales 0, 40, 80 o 160 g de proteína cruda/día en éstas formas durante cuatro meses. La suplementación incrementó significativamente la tasa de crecimiento, de 169 g/día en controles a 272 y 271 g/día en aquellos que recibieron torta de sésamo y de algodón respectivamente; no hubo diferenca estadística entre los grupos suplementados. Durate los cuatro meses de la estación seca inmediatamente después de que la suplementación fue suspendida, todos los grupos que habían sido suplementados crecieron sgnificativamente más rápido que los controls (P<0·05), indicando un efecto compensatorio en los suplementados. Durante ese período la media de crecimento de los grupos que recibieron torta de sésamo excedió a aquella de los que habían recibido torta de algodón (217 cf. 158 g/d;P<0·01). Los beneficios económicos de estos resultados fueron substanciales.

Comparaison entre le tourteau de sesame et la graine de coton comme sources complementaires de proteines pour les taurillons N'Dama sevres en Gambie
Résumé Le potentiel de réponse à de petites quantités supplémentaires de sous-produits proteiniques pour accroitre la productivité de bétail N'Dama, s'est révélé manifeste, dans les conditions d'élevage villageois en Gambie. De jeunes taureaux N'Dama ont été utilisés pour comparer le tourteau de sésame et la graine de coton en tant que source de complémentation protéinique pendant la saison sèche et le début de la saison humide au cours de l'année 1987. Ils ont re?u respectivement 0, 40, 80 ou 160 g de proteines brutes par jour sus ces deux formes pendat quatre mois. Cette supplémentation a accru de fa?on significative le taux de croissance, de 169 g/jour pour les témoins jusqu'à des moyennes de 272 et 271g/jour respectivement pour ceux qui ont re?u du tourteau de sésame et de la graine de coton. Quant aux groupes complémentés, il n'ont révélé aucune différence significative. Pendat les quatre mois de la saison sèche et immédiatement après l'arrêt de la supplémentation, tous les lots ayant fait précédemment l'objet d'une distribution complémentaire ont eu une croissance significativement plus rapide que les animaux témoins, du moins pourP<0,05, ce qui indique un effet important de report des suppléments. Durant cette période, le gain moyen des lots qui ont re?u le tourteau de sésame a dépassé celui des lots auxquels on a donné de la graine de coton, soit 217 g/jour contre 158 g/jour pourP<0,01. Les profits économiques de ces réponses ont été appréciables.
  相似文献   
102.
Data from the official milk recording scheme of the Austrian Simmental population were analysed to estimate variance components due to genomic imprinting. Traits regarded were milk yield, fat and protein content, persistency, days open (first, second and third lactation) and herd life. All dairy traits were preadjusted for BLUP herd‐year effects. After applying some data restrictions, the number of records ranged from 3391 (persistency, third lactation) to 33 993 (days open, first lactation). Two different estimation approaches were used: (i) estimation of the maternal and paternal gametic component by a dam and sire model, respectively, and (ii) estimation of the animal and an additional gametic component (maternal or paternal) by treating gametes as homozygous diploid individuals. All models also accounted for year of first calving and the cytoplasmic effect of maternal lineages. In tendency, the results of both approaches were fairly well in line with each other. For the majority of the investigated traits, no substantial imprinting effects were detected. Significant evidence of genomic imprinting on a multiple type I error ≤ 0.10 was only found for protein content and days open. For protein content in the second and third lactation, the proportions of variance due to the paternal gametic effect exceeded those of the maternal by 0.096 and 0.152, respectively. For days open in the second lactation, however, the proportion of variance of the maternal gamete effect exceeded that of the paternal by 0.036. In tendency, indication of paternal imprinting was found for all fitness‐related traits. For true and functional herd life, significant differences (pairwise type I error ≤ 0.05) of 0.040 and 0.032 were found between the proportions of variance due to the maternal and paternal gamete effect. Significant variance components of cytoplasmic effects (multiple type I error ≤ 0.01) were found for first lactation of milk yield (0.020), for first, second and third lataction of persistency (0.026, 0.035 and 0.033) and of days open (0.029, 0.016 and 0.022) and for true and functional herd life (0.019 and 0.029).  相似文献   
103.
The cervical patency of six domestic female cats was monitored under sedation by infusion of contrast medium (Omnipaque) into the cranial vagina during early oestrus, mid‐oestrus, late oestrus and interoestrus or a radiopharmaceutical (99mTc‐HSA) during mid‐ and interoestrus in a non‐ovulatory oestrous cycle. The transport of the contrast medium or the radiopharmaceutical through the cervix and within the uterine horns was observed under fluoroscopy and with the aid of scintigraphy. In three of the queens, transcervical transport of contrast medium was demonstrated in all stages of oestrus, in one queen during mid‐oestrus, late oestrus and 1 day after oestrus, and in two queens only during late oestrus. The relations between the cervical patency to the contrast medium and the oestrous behaviour, cornification of the vaginal cells and the serum oestradiol‐17β concentration were evaluated, and a relationship was found between the cervical patency and the degree of vaginal cornification. Transcervical transport of the radiopharmaceutical was observed in three queens during mid‐oestrus. When the cervix was open, hysterography under a fluoroscope and hysteroscintigraphy were performed. The fluoroscopic and scintigraphic recordings revealed the patterns of the uterine contractions during oestrus in both ascending and descending directions, and the movement of the uterine contents back and forth between the uterine horns. The hysterograms were classified according to the shape of the uterine horns and the appearance of the endometrial lining. Spiral‐shaped uterine horns with a smooth inner contour were observed in two queens, and a corkscrew appearance with irregular filling defects in the uterine lumen was shown in two queens that had developed subclinical cystic endometrial hyperplasia. These findings demonstrated that fluids or particles deposited in the cranial vagina of the cat can be transported into the uterus during some stages of the oestrous cycle. The fluoroscopic and scintigraphic techniques developed in this study may be further modified to permit more detailed studies of uterine contractile patterns and sperm transport in the feline female reproductive tract. Hysterography proved useful to diagnose uterine disease. The information on cervical patency is of value also for the development of techniques for artificial insemination in this species, and should be studied also in the ovulatory cycle.  相似文献   
104.
Abstract. Nitrous oxide (N2O) is involved in both ozone destruction and global warming. In agricultural soils it is produced by nitrification and denitrification mainly after fertilization. Nitrification inhibitors have been proposed as one of the management tools for the reduction of the potential hazards of fertilizer-derived N2O. Addition of nitrification inhibitors to fertilizers maintains soil N in ammonium form, thereby gaseous N losses by nitrification and denitrification are less likely to occur and there is increased N utilization by the sward. We present a study aimed to evaluate the effectiveness of the nitrification inhibitor dicyandiamide (DCD) and of the slurry additive Actilith F2 on N2O emissions following application of calcium ammonium nitrate or cattle slurry to a mixed clover/ryegrass sward in the Basque Country. The results indicate that large differences in N2O emission occur depending on fertilizer type and the presence or absence of a nitrification inhibitor. There is considerable scope for immediate reduction of emissions by applying DCD with calcium ammonium nitrate or cattle slurry. DCD, applied at 25 kg ha–1, reduced the amount of N lost as N2O by 60% and 42% when applied with cattle slurry and calcium ammonium nitrate, respectively. Actilith F2 did not reduce N2O emissions and it produced a long lasting mineralization of previously immobilized added N.  相似文献   
105.
106.
Pregnant goats were inoculated intravenously or in uterine arteries with Brucella abortus, and tissues from the uterus and placenta were examined by electron microscopy. Identification of B. abortus in placentae was with antibody-coated colloidal gold. B. abortus was first seen in phagosomes of erythrophagocytic trophoblasts and in the rough endoplasmic reticulum of chorioallantoic trophoblasts. Subsequently, trophoblast necrosis and ulceration of chorioallantoic membranes were present. Coincidently, B. abortus was present in the lumen of placental capillaries. In late stages of infection, placental vasculitis was present, and placentomal trophoblasts were separated from maternal syncytial epithelium. In lesions with vasculitis, large numbers of B. abortus were in connective tissue of chorionic villi. Within the placentome, trophoblasts that lined chorionic villi contained no intracellular bacteria and were separated from B. abortus by intact basement membranes. These results suggest that bacteremic B. abortus is endocytosed by erythrophagocytic trophoblasts and that B. abortus replicates in the rough endoplasmic reticulum of chorioallantoic trophoblasts. Replication of brucellae in trophoblastic rough endoplasmic reticulum is unique; we believe that B. abortus may utilize endoplasmic reticulum for synthesis and glycosylation of bacterial membrane proteins or that B. abortus catabolizes trophoblast secretory proteins.  相似文献   
107.
Components of the energy and heat balances were examined in two maize hybrids grown at three different plant densities (40, 70 and 100 thousand plants per hectare). One of the hybrids was drought tolerant, while the other was bred for cultivation under irrigated conditions. An increase in plant density influenced not only the size of the leaf area, but also the distribution of the leaves at various plant heights. The extinction coefficient, which provides a quantification of radiation penetration, was higher in the irrigated treatments. By contrast to the other two treatments, the plant canopy in the thinly sown stands remained open throughout the vegetation period, and thus behaved quite differently to the closed stands, making it impossible to compare them. Smaller albedo values were recorded for the hybrid bred for irrigation and in thinly sown stands. The low plant density allowed more energy to reach the soil, from which it was reflected, making a considerable contribution to the final temperature in the stand. The latent heat, in keeping with the quantity of water transpired, was the greatest in the densely sown stands. There was little difference between the latent heat values of the normal and dense stands in either hybrid, indicating that they both had a similar sensitivity to increased stand density. If sufficient water is available it would appear that the stand density could be increased even for the drought-tolerant hybrid.  相似文献   
108.
Abstract. Soil samples from a 32-year grassland field experiment were taken from 0–5, 5–10, and 10–15 cm soil depths in February 2002. Plots received annual treatments of unamended control, mineral fertilizer, three rates of pig slurry and three rates of cow slurry, each with six replicates. Samples were analysed for cation exchange capacity (CEC), exchangeable cations (Na+, K+, Ca2+, Mg2+), pH and Olsen P. Exchangeable sodium percentage (ESP) was calculated as a sodicity indicator. Mean ESP was generally greater for slurry treatments than the control, with a trend of increasing ESP with application rate. This was particularly marked for cow slurry. At 0–5 cm depth ESP increased from 1.18 in the control to 1.75 at the highest rate of pig slurry and 5.60 at the highest rate of cow slurry. Similar trends were shown for CEC, exchangeable Na+, K+ and Mg2+, Ca2+ and Olsen P. The build-up of soil P due to slurry applications, together with this combination of physical and chemical factors, may increase the risk of P loss to surface waters, particularly from soils receiving high rates of cow slurry.  相似文献   
109.
110.
This study tested different tags for each size of farm-reared gilthead sea bream, Sparus aurata L. juveniles, used in enhancement programmes. The following tags were tested: dye mark, fingerling tag, opercular tag, anchor tag A (filament diameter of 1.20 mm) and anchor tag B (0.85 mm). Tag/mark retention, wounds produced by the tag, ease of application, ease of detection and cost were examined. Epidermal dye marks had poor retention and detection rates. Of the tags tested, retention was greater for the anchor tag A (80–100%) after 7 months; anchor tag B showed a retention rate of only 20% after 3 months. The fingerling tag had a retention rate of 27.5% after 12 months. The opercular tag had a retention rate of 44% after 20 days but fractured the opercular bone in many cases. Tag incisions and wounds persisted in some fish for the duration of the experiment.  相似文献   
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