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Use of Straw and Wood Shavings as Nest Material in Primiparous does
Get PDFIn rabbit production several materials such as hay straw wood shavings or waste wool and cotton are used as nesting materials during parturition In this work straw and wood shavings were studied as potential materials for nest boxes and a choice test was designed for this purpose Two replicates of 30 primiparous does each were carried out Does were housed 10 d before parturition in a double commercial cage so each doe had access to 2 different nest boxes One of the nests was filled with 8 cm of barley straw and the other with 8 cm of wood shavings so the doe could choose which of them she prepared and gave birth in During the 24 h prior to parturition the state of the nest was assessed according to the mixing of the material and the does hair and the preservation of the original material as well as the chosen nest box When the does gave birth the number of live and dead newborn was recorded In the first replicate 87% of the does chose the straw nest box while in the second replicate 93% of the does did so The number of live kits at birth did not differ statistically for straw and wood shavings nests (8 36 +/- 1 74 vs 6 85 +/- 3 44) but litters reared in straw reacted a higher size at weaning (7 98 +/- 1 73 vs 6 29 +/- 3 35 P<0 05) Finally all the nests achieved a good level of mixing between the original material and the hair of the doe and only 5% of the does removed the original material (regardless of whether it was straw or wood shavings) and made the nest only with their hair In conclusion our results suggest that does might have a strong preference for straw rather than wood shavings as nest materia
Development of bovine blastocysts after in vitro fertilisation of oocytes derived from ovum pick up with sex-sorted sperm
No full textEffects of Different Oocyte Activation Procedures on Development and Gene Expression of Porcine Pre-Implantation Embryos
No full textAmong the factors that affect the efficiency of somatic cell nuclear transfer (SCNT) in pigs, the activation protocol is the most variable among the current SCNT procedures. The aim of this study is focused on defining an efficient activation treatment of porcine oocytes. In Experiment 1, we studied the effects of nine different oocyte activation procedures (including chemical-and electrical-based treatments) on parthenogenetic embryo development. In Experiment 2, we studied the effect of the more efficient activation procedures on the gene expression profile of Oct4 and Igf2r in parthenogenetic blastocysts. In conclusion, ionomycin as a first calcium stimulus is not able to activate porcine oocytes efficiently in comparison with electric procedures. Electrical treatments with 6-DMAP significantly increased the level of Oct4 expression, whereas the single and double pulse treatments alone maintained the same profile as the IVF group
Efficiency of Repeated In Vivo Oocyte and Embryo Recovery After rhFSH Treatment in Rabbits
No full textThis study aims to assess the efficiency of in vivo oocyte and embryo recovery after a recombinant human FSH (rhFSH) treatment in rabbit does. Females were distributed in two experimental groups: donor does were treated with rhFSH (superovulation group) for 3 days prior to artificial insemination (embryo recovery) or ovulation induction (oocyte recovery) and does without treatment remained as the control group. Mature oocytes or embryos were collected with the laparoscopy technique 16 h after ovulation induction (oocytes) or 72 h after artificial insemination (embryos). Up to four recoveries were performed with each doe. Recovery efficiencies differed significantly between embryos (84%) and oocytes (58%). Yet, the recovery rates for the superovulation and control groups did not differ. The rhFSH group was associated with a significant increase (p < 0.05) in the number of oocytes and embryos recovered in comparison with the control group (10.2 +/- 1.0 and 14.3 +/- 1.2 vs 6.0 +/- 2.7 and 8.4 +/- 2.3 for oocytes and embryos, respectively). Results from this study indicate that repeated in vivo oocyte and embryo recovery from rhFSH superovulated does maximizes the number of oocytes or embryos collected from the same female
Differential gene expression analysis provides new insights into the molecular basis of iron deficiency stress response in the citrus rootstock Poncirus trifoliata (L.) Raf.
Get PDFIron chlorosis is one of the major abiotic stresses affecting fruit trees and other crops in calcareous soils and leads to a reduction in growth and yield. Usual remediation strategies consist of amending iron to soil, which is an expensive practice, or using tolerant cultivars, which are difficult to develop when not available. To understand the mechanisms underlying the associated physiopathy better, and thus develop new strategies to overcome the problems resulting from iron deficiency, the differential gene expression induced by iron deficiency in the susceptible citrus rootstock Poncirus trifoliata (L.) Raf. have been examined. The genes identified are putatively involved in cell wall modification, in determining photosynthesis rate and chlorophyll content, and reducing oxidative stress. Additional studies on cell wall morphology, photosynthesis, and chlorophyll content, as well as peroxidase and catalase activities, support their possible functions in the response to iron deficiency in a susceptible genotype, and the results are discussed
Efficacy of Neoseiulus californicus and Phytoseiulus persimilis in suppression of Tetranychus urticae in young clementine plants
No full textTetranychus urticae is one of the most damaging tetranychid mites affecting clementine orchards in Spain, where natural control is insufficient. Furthermore, in clementine nurseries, tender foliage is highly susceptible to attack and natural enemies are almost always absent. Therefore, acaricides are often used indiscriminately. Alternative control measures are necessary, both in commercial orchards and clementine nurseries. In order to assess the efficacy of inoculative releases of N. californicus and P. persimilis to reduce T. urticae populations in young Spanish clementine plants, a semi-field experiment was conducted and repeated in three seasons (spring, summer and autumn). Phytoseiulus persimilis was highly effective in reducing both T. urticae infestations and the damage level inflicted on plants at both release rates evaluated (40 and 80 phytoseiids/plant) and all three periods considered. By contrast, N. californicus demonstrated low performance under certain conditions. The results of this study could be adapted and transferred to nurseries and young citrus plantations
Advances in Botanical Research
No full textHigh yield and product quality of crops grown in soilless systems are only possible if nutrition is optimized. This implies the accurate management of all factors involved in crop nutrition: nutrient solution composition, water supply, nutrient solution temperature, dissolved oxygen concentration, electrical conductivity and pH of the nutrient solution. If any of these factors is under non-optimal conditions, plants may suffer from stress leading to a decline of yields and product qualities. In order to specify the range of optimal conditions of a particular crop, a precise diagnosis of plant stress caused by an incorrect management of any of above mentioned factors is needed. This review analyses, for every factor, the aspects that need to be considered while determining the optimum ranges and the physiological methods that can be used to diagnose plant stress at non-optimal conditions. The most extensively used methods of plant stress assessment include measurements of: photosynthetic activity (leaf gas exchange, chlorophyll fluorescence, pigment content and related enzyme activities), oxidative stress and antioxidant capacity, content and partitioning of several compounds in the plant (carbohydrates, hormones, amino acids and nutrient elements), activity of specific enzymes, plant water relationships and expression of specific genes
Response of plum trees to deficit irrigation under two crop levels: tree growth, yield and fruit quality
No full textThe effects of regulated deficit irrigation (RDI) and crop load on Japanese plum were investigated. RDI applied during phase II of fruit growth and post-harvest was compared with irrigation to match full crop evapotranspiration. Each irrigation treatment was thinned to a commercial crop load (described as medium) and to approximately 40% less than the commercial practice (described as low). The RDI strategy allowed for 30% water savings, increasing tree water use efficiency, with minimal effect on crop yield and fruit growth providing that plant water stress during the fruit growth period was low (stem water potential > -1.5 MPa), trees could recover optimum water status well before harvest, and crop load was low. However, the economic return, calculated from fruit weight distribution by commercial categories, was more affected by RDI than yield. The combination of medium crop load and RDI shifted fruit mass distribution towards the low value categories. This lead to similar or even higher economic returns in the RDI treatment with low crop level than with the medium one. In addition, since both, low crop level and RDI, increased fruit total soluble solids (TSS) concentration, fruit under RDI and low crop levels had the highest values of TSS
Response of grapevine cv. 'Tempranillo' to timing and amount of irrigation: water relations, vine growth, yield and berry and wine composition
No full textThe effects of several moderate irrigation regimes on vine water status, yield, and must and wine composition, were investigated during five seasons in a vineyard planted with Vitis vinifera cv. Tempranillo. Treatments consisted of non-irrigated vines and six differentially irrigated treatments with contrasting watering regimes during the pre-veraison and post-veraison periods. There were large differences in yield and grape and wine quality responses to irrigation among seasons, probably as consequence of the different environmental conditions and crop levels. It was, however, clear that vines benefit more of the irrigation supplied in years of high yield levels. Across seasons, yield increased in proportion to the amount of water applied mostly due to the larger berries of irrigated vines, and there was no clear response to the timing of irrigation supplied. In addition, there were no carry over effects due to irrigation on bud fertility. The post-veraison water application was necessary to increase must sugar level and wine alcohol content. However, water restrictions during the pre-veraison period lead to more concentrated berries in terms of total phenolic and anthocyanins. The only noticeable detrimental effect of irrigation, regardless of the timing of its application, on wine composition was an increase in wine pH
Polyembryony in non-apomictic citrus genotypes
No full textAdventitious embryony from nucellar cells is the mechanism leading to apomixis in Citrus sp. However, singular cases of polyembryony have been reported in non-apomictic genotypes as a consequence of 2x x 4x hybridizations and in vitro culture of isolated nucelli. The origin of the plants arising from the aforementioned processes remains unclear. The genetic structure (ploidy and allelic constitution with microsatellite markers) of plants obtained from polyembryonic seeds arising from 2x x 4x sexual hybridizations and those regenerated from nucellus culture in vitro was systematically analysed in different non-apomictic citrus genotypes. Histological studies were also conducted to try to identify the initiation process underlying polyembryony. All plants obtained from the same undeveloped seed in 2x x 4x hybridizations resulted from cleavage of the original zygotic embryo. Also, the plants obtained from in vitro nucellus culture were recovered by somatic embryogenesis from cells that shared the same genotype as the zygotic embryos of the same seed. It appears that in non-apomictic citrus genotypes, proembryos or embryogenic cells are formed by cleavage of the zygotic embryos and that the development of these adventitious embryos, normally hampered, can take place in vivo or in vitro as a result of two different mechanisms that prevent the dominance of the initial zygotic embryo