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Tropical Animal Health and Production - To evaluate the effect of partial replacement of a concentrate with Daniellia oliveri (DO) foliage on voluntary intake, digestibility, nitrogen utilization,...  相似文献   
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The aim of this study was to investigate the course of expression of platelet‐activating factor (PAF), PAF‐receptor (PAF‐R), epidermal growth factor (EGF), EGF‐R, vascular endothelial growth factor (VEGF), VEGF‐R1 and VEGF‐R2 in uterine tissue during canine pregnancy. For this purpose, 20 bitches were ovariohysterectomized at days 10–12 (n = 10), 18–25 (n = 5) and 28–45 (n = 5) days after mating, respectively. The pre‐implantation group was proven pregnant by embryo flushing of the uterus after the operation, the others by sonography. Five embryo negative, that is, non‐pregnant, bitches in diestrus (day 10–12) served as controls. Tissue samples from the uterus (placentation sites and horn width, respectively) were excised and snap‐frozen in liquid nitrogen after embedding in Tissue Tec®. Extraction of mRNA for RT‐PCR was performed with Tri‐Reagent. In the embryos, mRNA from all factors except VEGF was detected. In the course of pregnancy, significantly higher expression of PAF and PAFR as well as VEGF and VEGFR2 during the pre‐implantation stage than in all other stages and a strong upregulation of EGF during implantation were characteristic. The course of EGF was in diametrical opposition to the course of the receptor. These results point towards an increased demand for VEGF, EGF and PAF during the earliest stages of canine pregnancy.  相似文献   
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Forty-eight rabbits used to investigate the response of growing rabbits to diets containing differently processed cassava peel meals were divided into four groups balanced for sex and weight. These groups were then assigned at random to the experimental treatments. Four diets were formulated such that the diets contained 200 g/kg of the experimental feedstuffs, sun-dried cassava peel meal (S), ensiled cassava peel meal (E) and retted cassava peel meal (R), and the control did not contain any cassava peels. Hydrogen cyanide (HCN) concentration in the processed cassava peel meal was lower relative to the unprocessed meal. It was, however, lowest in R and highest in E. With the exception of S, fibre fractions were lower in the processed meal compared to the unprocessed meal. The E depressed (p < 0.05) feed and digestible nutrient intakes, weight gain, nutrient digestibility, digestible protein (DP), digestible energy (DE) and DP/DE ratio but increased protein intake to gain and feed to gain ratios compared to other diets. Intake of HCN decreased (p < 0.05) successively in this order: R, S and E. The results indicate that retting and sun-drying are more effective in cassava peel detoxification than ensiling, and dietary HCN concentration and intake of 56 and 4 mg/kg BW, respectively, were not toxic under the conditions of the experiment.  相似文献   
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Mesenchymal stem cells (MSC) are multipotent progenitor cells defined by their ability to self‐renew and give rise to differentiated progeny. Previous studies have reported that MSC may be induced in vitro to develop into different types of specialized cells including male gametes. In vitro gamete derivation technology has potential applications as an alternative method for dissemination of elite animal genetics, production of transgenic animals and conservation of endangered species. This study aimed at investigating the in vitro effect of BMP4, TGFβ1 and RA on the potential for germ cell (GC) differentiation of bovine foetal MSC (bfMSC) derived from bone marrow (BM). The effect of BMP4, TGFβ1 and RA was analysed on the expression of pluripotent, GC and male GC markers on bfMSC during a 21‐day culture period. bfMSC cultured under in vitro conditions expressed OCT4, NANOG and DAZL, but lacked expression of mRNA of VASA, STELLA, FRAGILIS, STRA8 and PIWIL2. Treatment with exogenous BMP4 and TGFβ1 induced a transient increase (p < .05) in DAZL and NANOG mRNA levels, respectively. However, exposure to RA was more effective in increasing (p < .05) expression of DAZL and regulating expression of OCT4 and mRNA levels of NANOG. These data suggest that bfMSC may possess potential for early GC differentiation, where OCT4, NANOG and specially DAZL may play significant roles in controlling progression along the GC lineage.  相似文献   
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This study assessed ecological and socio-economic impacts of a participatory forest management project in the Republic of Benin. The study focused on the Wari-Maro Forest Reserve and the ‘Projet d’Aménagement des Massifs Forestiers’ five years after its completion. A forest inventory was carried out using 37 square plots of 729 m2 each to characterise the population structure of two types of plantations established: plantations with exotic species and plantations with native species. In addition, individual surveys were conducted with local households, organs of joint forest management and forestry officers to evaluate their perceptions about the participatory management of the plantations. Finally, the sustainability of the participatory management was assessed with an established rating system. Results showed that plantations with exotic species were more successful than plantations with native species. Local communities argued that they have not been involved in the plantations design but only in the implementation step and that their standards of living have decreased after the project completion. The rating system used showed that the participatory management of plantations had a short-term sustainability. The findings suggest that future projects should be designed and implemented with better participation of local communities as full partners.  相似文献   
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This study evaluated effects of increasing levels of dried rumen contents (DRC) on voluntary intake, growth performance, digestibility, nutritive value, N utilization, microbial protein supply (MPS), and purine derivatives excretion (PDE) of lambs fed with Afzelia africana basal forage. Sixteen lambs (13.7?±?0.1 kg body weight (BW)) were randomly assigned to one of the four eight diets containing 0, 200, 400 and 600 g DRC/kg dry matter (DM) in a completely random design. Intakes of concentrate, DM, crude protein (CP), organic matter (OM), digestible CP (DCP), digestible OM (DOM), digestible energy (DE) and metabolizable energy (ME), CP and OM digestibility, DOM, DCP, DE, ME, N intake and retention, weight gain, cost/kg BW gain, MPS and PDE increased with increasing DRC level up to 400 g/kg DRC and declined at 600 g/kg DRC (P?<?0.05; 0.01). Feed conversion ratio and DM digestibility declined as DRC level increased from 0 to 400 g/kg and peaked at 600 g/kg DRC (P?<?0.05; 0.01). Forage intake and DE/DCP ratio decreased (P?<?0.05; 0.01) progressively with increasing DRC level. Results indicate that DRC can be incorporated up to 400 g/kg in a compounded ration for sheep.  相似文献   
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The effects of prepartum supplementary feeding on the productive and reproductive performance were investigated using grazing gestating Bunaji cows with an average initial body weight of 294.50 ± 3.75 kg. Twenty cows were allocated to a completely randomized design, with five animals per treatment. The treatments were: A, range grazing (RG); B, RG + 100% corn bran (CB); C, RG + 60% CB + 40% palm kernel cake (PKC), and D, RG + 60% CB + 40% dried brewer’s grains (DBG). The average daily gains (ADG) and body condition scores (BCS) of supplemented cows were significantly better than the non-supplemented cows. Postpartum weight loss was markedly reduced in supplemented cows compared to their non-supplemented counterparts. Mean milk offtake and mean milk yield per lactation were significantly lower in non-supplemented cows than the supplemented ones. Among the supplemented cows, ADG, BCS, mean milk offtake and milk yield per lactation were significantly better for cows on treatments C and D than those on treatment B. Though insignificant, longest lactation length (LL) and shortest calving interval were obtained for supplemented cows. Calf’s birth weight was similar among the treatments. Milk yield was significantly influenced (R2 = 0.8601) by cow’s weight, BCS and LL.  相似文献   
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SUMMARY Cashmere goats and Merino sheep were grazed together at 7.5 animals per ha on annual rye grass and clover pasture in southern Victoria, a winter rainfall area. Intake of parasitic larvae was measured in oesophageal extrusa samples collected from 2 animals of each species, 4 times in one week, on 7 occasions between mid-March (autumn) and mid-June (winter). Pasture contamination with larvae was measured at the same times. The number of larvae per kg of green grass was lower than on green clover; the most heavily contaminated portion of the pasture was the mat of dead herbage on the ground. The diet selected by goats contained more green grass and dead herbage and less clover that that of sheep (P < 0.01). Goats ingested 643 infective trichostrongylid larvae per kg dry matter intake (DMI) versus 274 per kg DMI for sheep in autumn, increasing to 1892 versus 1143 in early winter. The heavier trichostrongylid burdens of goats compared with sheep, when grazed together, are due in part to greater rates of infection consequent on different grazing patterns as well as greater susceptibility to infection.  相似文献   
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