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121.
122.
Ginja MM Silvestre AM Colaço J Gonzalo-Orden JM Melo-Pinto P Orden MA Llorens-Pena MP Ferreira AJ 《Veterinary journal (London, England : 1997)》2009,182(2):275-282
Three hundred and thirteen Estrela mountain dogs were examined for hip dysplasia (HD) using the standard ventrodorsal hip extended view, and graded into five categories (A, B, C, D and E) using the Fédération Cynologique Internationale’s (FCI) scoring system. The Ortolani method was performed to evaluate hip joint laxity. Pedigree information was obtained from the Portuguese Kennel Club and the genetic trend was evaluated by calculating the mean breeding values (BVs) for the last 15 years, using the threshold model.HD was found in 66% of the dogs. There was low-moderate correlation between the results of the Ortolani test and FCI hip scores (rs = 0.386; P < 0.001). Grades of hip dysplasia were equal in both males and females (P = 0.14) and in the animals’ right and left sides (P = 0.51). The mean BVs for HD were stable in dogs born between 1991 and 2003, and showed an improvement in 2004 and 2005. The data confirm the high prevalence and severity of HD in predisposed breeds that do not have breeding programmes in place. It also confirms an initial favourable change in BVs that is a likely consequence of the voluntary radiographic hip-screening programme. 相似文献
123.
MP Viudes-de-Castro I Salvador F Marco-Jiménez EA Gómez MA Silvestre 《Reproduction in domestic animals》2009,44(4):576-579
The site where the semen is deposited appears to be one of the most important factors affecting pregnancy of inseminated goats. In Murciano–Granadina (MG) goats, post-cervical insemination is achieved in a limited number of females. An effective way to increase fertility rate could be by increasing post-cervical inseminations. Effect of exogenous oxytocin application to facilitate the cervical penetration and its effect on kidding rate and prolificacy in MG goats were investigated. Oestrus was synchronized using progesterone-impregnated sponges for 11 days. Females were randomly divided into three groups (n = 190) and received either an i.v. injection of 100 or 200 IU of oxytocin or saline solution 15 min before being inseminated. Data on semen deposition depth were recorded for each animal using a catheter scaled in centimetres (up to 4 cm). Depth of semen deposition was affected by the oxytocin treatment (p < 0.05). Oxytocin enhanced cervical passage only with the dose of 200 IU compared with the control group, increasing the deposition depth (2.9 cm vs 1.9 cm). No significant effect of oxytocin treatment on kidding rate and prolificacy was detected. Depth of semen deposition affected kidding rate (p < 0.01). In conclusion, oxytocin treatment improved the depth of semen deposition in AI of MG goats, but kidding rate and prolificacy was not affected. More studies must be conducted to assess the minimal effective dose required for sufficient cervical dilation, and to determine the effects of such doses of oxytocin on uterine motility, sperm transport and fertility in goats. 相似文献
124.
R Leoci G Aiudi A De Sandro Salvati F Silvestre F Binetti GM Lacalandra 《Reproduction in domestic animals》2009,44(S2):326-328
Therapeutic ultrasound (1.5 W/cm2 ) was investigated for its effect upon testicular size and consistency and semen quality in five dogs. Dogs were treated every other day with a total of three treatments and were examined up to 2 weeks after treatment. There was some tenderness after treatment and a significant decrease in testicular size and semen quality. This method may provide a suitable contraception technique in dogs and requires further investigation. 相似文献
125.
E García-Roselló E García-Mengual P Coy J Alfonso MA Silvestre 《Reproduction in domestic animals》2009,44(1):143-151
Intracytoplasmic sperm injection (ICSI) is a powerful technique in the field of assisted reproduction (ART) and provides exciting opportunities for studying the basic mechanisms of fertilization and early embryo development. Nevertheless, its application in agriculture and conservation biology has been greatly hampered by the low success rate reported for this method in respect of economically important species. Specifically, the rates of blastocyst formation and live newborn are greatly reduced when zygotes are generated by ICSI. Except for humans, ICSI remains a low efficiency technology in comparison with alternatives such as in vitro fertilization (IVF) and its application is less widespread. In this paper, we discuss the present status, applications and factors affecting ICSI in pigs and other species. 相似文献
126.
RA McKenzie AN Gordon BG Burren JA Gibson MP Gardner 《Australian veterinary journal》2009,87(3):113-115
Nitrate–nitrite poisoning killed four adult alpacas and induced the abortion of a full-term fetus after access to oaten hay ( Avena sativa ) containing 3.2% KNO3 equivalent in dry matter. Necropsy findings were cyanosis, dark-coloured blood, and pulmonary congestion and oedema. Aqueous humour from two adults contained 25 mg NO3 /L and that from the fetus contained 10 mg NO3 /L. Cyanide poisoning possibly killed two adult wether alpacas that ate a garden-cultivated variety of Osteospermum ecklonis (South African daisy, bietou) with a cyanide potential of 6800 mg HCN/kg dry matter. 相似文献
127.
Geneau-Sbartaï C Leyris J Silvestre F Rigal L 《Journal of agricultural and food chemistry》2008,56(23):11198-11208
Nowadays, the end-of-life of plastic products and the decrease of fossil energy are great environmental problems. Moreover, with the increase of food and nonfood transformations of renewable resources, the quantities of agro-industrial byproducts and wastes increase hugely. These facts allow the development of plastic substitutes made from agro-resources. Many researches show the feasibility of molding biopolymers extracted from plants like a common polymeric matrix. Other natural macromolecules are used like fillers into polyolefins, for example. However, limited works present results about the transformation of a natural blend of biopolymers into a plastic material. The aim of this study is the determination of the composition of sunflower cake (SFC) and also the characterization of its components. These were identified by chemical and biochemical analysis often used in agricultural or food chemistry. Most of the extraction and purification processes modify the macrostructure of several biopolymers (e.g., denaturation of proteins, cleavage or creation of weak bonds, etc.). So, the composition of different parts of the sunflower seed (husk, kernel, and also protein isolate) was determined, and the plasticlike properties of their components were studied with thermogravimetric analysis, differential scanning calorimetry, and a dynamic mechanical thermal analysis apparatus. Finally, this indirect way of characterization showed that SFC can be considered a natural composite. In SFC, several components like lignocellulosic fibers [40%/dry matter (DM)], which essentially come from the husk of sunflower seed, can act as fillers. However, other biopolymers like globulins ( approximately 30% of the 30% of sunflower seed proteins/DM of SFC) can be shaped as a thermoplastic-like material because this kind of protein has a temperature of glass transition and a temperature of denaturation that seems to be similar to a melting temperature. These proteins have also viscoelastic properties. Moreover, SFC has similar rheological properties and other physicochemical properties compatible with shaping or molding behaviors of plastic-processing machinery. 相似文献
128.
129.
Helminth infection, species diversity (proportion of each species in the community), species number, intensity of infection and anthelmintic resistance were investigated in 16 dairy-goat farms of south-western France. The aim of the study was to estimate which breeding management factors may affect diversity and intensity of infection. Anthelmintic resistance was investigated because this factor may modify composition of nematode communities. Farm history and breeding management were recorded by means of a questionnaire. Natural and experimental infections were compared to determine which strategy was the best to estimate diversity index and number of species from nematode community of a whole herd. A total of 17 species of helminths, among which 14 nematodes, one cestode (Moniezia spp.) and two trematodes (Paramphistomum daubneyi and Dicrocoelium lanceolatum) were recovered in the 26 necropsied culled goats. One culled goat worm burden represented conveniently species number but not species diversity (Shannon index) of parasite community harboured in the whole herd. Experimental sheep infection with larvae from pooled faeces of 15 goats was the best strategy to estimate species diversity in farms. Diversity could be predicted from the number of farms from which goats originated at constitution of the herd, the duration of goat winter withdrawal from pastures, and intensity of infection. Anthelmintic resistance was correlated with the number of farms of origin, area of permanent pastures and intensity of infection. The strategy adopted for the herd constitution was a critical step as species diversity and risk of anthelmintic resistance increased with the number of farms of origin. Intensity of infection was negatively correlated with species diversity. This suggested that more diverse communities were better controlled by the host, in agreement with the widespread statement that diversity would beget stability. 相似文献
130.
The aim of this research was to study the effect of changing female stimulus on libido and semen characteristics from young Murciano-granadina male goats submitted to intensive semen collection using females not in estrus as teasers. Males were submitted to two different sexual stimulation procedures. In the first procedure, the same doe was used as the female stimulus for three consecutive presentations. In the second, the doe was replaced after the second presentation by a new female. Semen volume, concentration, forward progressive motility, and live spermatozoa were scored. To analyze reaction time (RT), three types of analysis were performed. In the first one, RT was analyzed by multifactor ANOVA, taking as a missing value 300 s when a buck did not ejaculate. In the second, RT also was analyzed by multifactor ANOVA, but data from males that did not ejaculate were removed. In the third, a Cox Survival analysis was carried out by censoring data when a buck did not ejaculate within 5 min of entering the test arena. A decrease in semen volume and sperm concentration in the successive ejaculations was observed, being highly marked in the third ejaculation independent of the stimulation procedure (0.62 vs. 0.38 and 0.43 mL, and 2,828 vs. 2,183 and 2,223 million spermatozoa/mL to the first and third ejaculation respectively; P < 0.05). No significant differences were observed either in forward progressive motility or live sperm rate. Changing the female stimulus in the third presentation had no significant effect on any seminal characteristic. Regarding libido and mounting behavior variables, there was a substantial decrease in RT in the third service when the female was changed (with both types of ANOVA). When censored data were taken into account, the relative risk showed that the probability of a male ejaculating in the third presentation increased almost fourfold when the female was replaced than when the female was the same in all services (P < 0.05). In conclusion, young Murciano-granadina bucks can be used as semen donors because none of the most important semen variables used to reject or accept an ejaculate before freezing process decreased after intensive semen collection. We also recommend changing the female stimulus to make the semen collection procedure more efficient and using survival analysis methodology to analyze time data, mainly when a high rate of censored data are scored. 相似文献