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71.
Thirty-six 1.0-year-old Liao Ning Cashmere goat wethers (BW = 22.01 ± 0.59 kg) were used to determine the effects of dietary zinc (Zn) level on the performance, nutrient digestibility and plasma Zn status during the cashmere fiber growing period. The goats were randomly divided into four groups that were fed a basal diet containing 22.3 mg Zn/kg dry matter (DM) with 0, 15, 30 or 45 mg Zn/kg DM as reagent grade ZnSO4·7H2O. The experiment lasted 60 days including a 7-day metabolism trial. Both average daily gain (ADG) and feed efficiency were improved (P < 0.05) by Zn supplementation and were higher (P < 0.05) for the treatment groups supplemented with 30 and 45 mg Zn/kg DM compared with 15 mg Zn/kg DM. Zn supplementation had no influence on the length and diameter of cashmere fiber (P > 0.05). Digestibility of DM, crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) did not differ among treatments (P > 0.05). Plasma Zn concentrations were increased (P < 0.01) by Zn supplementation and were higher (P < 0.05) for the treatment groups supplemented with 30 and 45 mg Zn/kg DM compared with 15 mg Zn/kg DM. Zn apparent absorption rate and apparent retention rate were decreased (P < 0.05) by Zn supplementation, but did not differ among Zn supplemented treatments (P > 0.05). In conclusion, a control diet containing 22.3 mg Zn/kg DM was inadequate for achieving optimal growth performance in Cashmere goats, and the recommended level of dietary Zn for such goats is 52.3 mg/kg DM during the cashmere fiber growing period.  相似文献   
72.
In the present paper we describe Corynebacterium pseudotuberculosis infection in the Saanen × Kilis crossbred goats with abscesses located in retropharyngeal (n = 29), mandibular (n = 49), parotid (n = 26), superficial cervical (n = 40), subiliac (n = 23) and popliteal (n = 11) lymph nodes. The most prominent site of the abscesses was in the anterior half of the body affecting 80.89% of the goats. Histopathological examination of the lymph nodes showed pyogranulomatous inflammation. The goats were randomly assigned to either kanamycin treatment group or a placebo. The efficacy of kanamycin was assessed clinically and on the basis of a lesion score derived from the examination of the affected lymph nodes. Clinical evaluations and lesion scoring were done by the same veterinary investigator. Both owners and the veterinary investigator were blinded to the allocation to the groups. Throughout the study kanamycin treatment significantly decreased (P < 0.05) the investigator's clinical scores while no significant changes were detected in the placebo group.  相似文献   
73.
This study utilizes pooled agricultural region data for the 1982–1987 period to estimate the short-run supply of sheep and goats in Botswana. Elasticity estimates indicate that a 1% increase (decrease) in rainfall at year t leads to a 0.53% rise (fall) in goat marketing in year t+1, and that a 1% rise (fall) in goat population (inventory) leads to a 0.15% rise (fall) in goat sales. The sheep equation reveals that a 1% increase (decrease) in sheep inventory results in a 1.23% rise (fall) in the number of sheep marketed, and suggests that rainfall has no impact on sheep sales. It is argued that the inelastic response of goat sales to changes in goat inventory reinforces the general view that livestock in Botswana are treated as a store of wealth, rather than as primarily a commercial activity for generating cash incomes. This tendency seems to be reduced in the case of sheep, where an elastic response of sales to changes in sheep inventory is observed. Producer prices are found to have no impact on small ruminant sale. The lack of responsiveness of supply to prices may be revealing the existence of inadequate access by most producers to organized markets for small ruminants. It is further argued that without promoting the development of such markets, other developmental efforts, particularly those geared at improving farm-level productivity will yield no positive outcomes, as farmers lack the cash incentive to invest in improved management and husbandry practices.  相似文献   
74.
The prevalence and intensity of oocysts of coccidia, particularly Eimeria species, and eggs of gastrointestinal nematodes in kids (2–4 months), young goats (5–12 months) and adult goats (>1 year) were determined in five large herds managed extensively in five villages in the dry zone. Of the representative samples examined, oocysts were found in 88% of kids, 91% of young goats and 83% of adults. Seven species of Eimeria were identified in faecal samples by salt flotation. Eimeria ninakohlyakimovae (31%), E. alijevi (29%) and E. arloingi (21%) were the most common species in all age categories. Other species encountered were E. christenseni (7%), E. jolchijevi (6%), E. hirchi (3%) and E. aspheronica (1%). Gastrointestinal nematode eggs were found in 89% of the kids, 94% of the young goats and 84% of the adult goats. Identification of gastrointestinal nematodes revealed Haemonchus contortus (90%) followed by Oesophogostomum spp. (8.5%) and Trichostrongylus spp. (1%) in all three age categories examined. Both Eimeria and gastrointestinal nematodes were found in 77% of the kids, 86% of the young goats and 71% of adult goats. The mean oocyst counts per gram of faeces in kids, young goats and adult goats were 9728, 1946, and 2667, respectively. The oocyst counts were not different significantly between age groups (P>0.05). The mean egg counts per gram of faeces in kids, young goats and adult goats were 1217, 1641 and 1092, respectively. The egg counts in kids were significantly lower than that in young goats (P<0.05). The intensity of Eimeria and gastrointestinal nematode infections between herds were significantly different (P<0.01).  相似文献   
75.
Despite an estimated global goat population of over one billion, little is known about methods being used to feed milk to artificially reared kids (reared away from their dams) and how kids are weaned from these systems. Quantifying and characterising current methods utilised on farms will enable future targeted research to investigate best practice methods for milk feeding and weaning of artificially reared kids. A recall-based survey that investigated on-farm kid-rearing practices (focusing on the milk feeding and weaning stages) was distributed via social media, and regional goat organisations across multiple countries. A total of 242 responses from 16 countries were collected and geographically grouped. Responses that could not be grouped sufficiently were removed (nine responses from eight countries). A total of 233 responses from eight countries (United States of America (USA) 72; United Kingdom (UK) 71; Australia 33; Canada 23; New Zealand 20; European Union (EU) 14), were analysed. Most farms (217; 93%) bred their own kids. The most common milk feeding method was bottle feeding, used on 135 farms (57.9%), followed by ad libitum feeding used by 72 (30.9%). A relationship between number of kids reared and feeding system was identified, χ2(3, N = 233) = 89.605, P < 0.001, with farms rearing > 100 kids more likely to feed milk ad libitum. A total of 170 farms (72.9%) were weaned based on a target age and 85 (36.4%) on a target weight, 53 (22.7%) used both and 45 (19.3%) neither. Target weaning ages and weights varied across countries; the median age was 84 days (interquartile range (IQR) 56–84), and the median weight was 16 kg (IQR 15–18). A difference was found between milk feeding systems for weaning method (Χ2(2, N = 232) = 63.797, P 0.001), with kids most likely to be abruptly weaned from ad libitum systems (or gradually weaned from bottle feeding). Abrupt weaning was used by 67 farms (28.8%), and gradual weaning was used by 165 (71.1%). Gradual weaning strategies included reducing milk quantity (150 farms; 93% of farms providing detail) and diluting milk (six farms; 4%). A total of 169 (72.5%) supplied enrichment that met the survey’s definition; items to climb on/hide in were most common, provided by 157 farms (92.8%). Findings suggest differing practices in smaller-scale bottle-fed versus larger-scale ad libitum milk systems, likely reflecting differing system needs. This highlights a requirement for welfare-focused research in kids reared artificially in order to identify and communicate best practices to ensure on-farm welfare is optimised within each system.  相似文献   
76.
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78.
This study was conducted to evaluate the effects of the dietary ratio of ruminal degraded protein (RDP) to ruminal undegraded protein (RUP) and the dry matter intake (DMI) on the intestinal flows of endogenous nitrogen (N) and amino acids (AA) in goats. The experiment was designed as a 4 × 4 Latin square using four ruminally, duodenally and ileally cannulated goats. The treatments were arranged in a 2 × 2 factorial design; two ratios of RDP to RUP (65:35 and 45:55, RDP1 and RDP2, respectively) and two levels at 95% and 75% of voluntary feed intake (DMI1 and DMI2, respectively) were fed to the goats. There were no significant differences in the N intake, duodenal flow of total N, undegraded feed N, microbial N, endogenous N or ileal flow of endogenous N, but the duodenal and ileal flow of endogenous N numerically decreased by approximately 22% and 9%, respectively, when the feed intake changed from DMI1 (0.63 kg/d) to DMI2 (0.50 kg/d). The dietary ratio of RDP to RUP had significant effects (p < 0.05) on the ileal flows of endogenous leucine, phenylalanine and cysteine. The present results implied that the duodenal flows of endogenous N and AA decreased when the dietary RDP to RUP ratio and DMI decreased, and the flow of endogenous AA at the ileum also decreased when the DMI decreased but increased with decreasing RDP to RUP ratios.  相似文献   
79.
The objective of this study was to evaluate the effectiveness of supplementation of cellulase and xylanase to diets of growing goats to improve nutrient digestibility, utilisation of energy and mitigation of enteric methane emissions. The experiment was conducted in a 5 × 5 Latin square design using five goats with permanent rumen fistulae and five treatments consisted of two levels of cellulase crossed over with two levels of xylanase plus unsupplemented Control. The cellulase (243 U/g) derived from Neocallimastix patriciarum was added at 0.8 and 1.6 g/kg dry matter intake (DMI) and the xylanase (31,457 U/ml) derived from Aspergillus oryzae was fed at 1.4 and 2.2 ml/kg DMI. There were no differences in apparent digestibility of organic matter, neutral detergent fibre, acid detergent fibre and rumen fermentation parameters (i.e. ammonia-nitrogen [N], volatile fatty acids) among all treatments. Dietary cellulase and xylanase addition did not influence energy and N utilisation. But compared to xylanase addition at the higher dose, at the low xylanase dose the retained N, the availability of retained N and digested N were increased (< 0.01). Moreover, enzyme addition did not affect the enteric methane emission and community diversity of ruminal methanogens. The present results indicated that previous in vitro findings were not confirmed in ruminant trials.  相似文献   
80.
动物模型BLUP法估计内蒙古白绒山羊育种值的研究   总被引:4,自引:0,他引:4  
应用动物模型BLUP法估计了阿尔巴斯白绒山羊种羊场1989-1998年共10个年度3981只个体的抓绒量和体重的单性状育种值,以及这两个性状的综合育种值。在模型中考虑的固定效应有年龄效应和性别-群体-年度效应、随机效应有个体的加性效应和个体永久性环境效应。比较育种值选择与表型值选择的结果表明:⑴公羔依据断乳重选择与依据育咱值选择的结果差异较大;⑵育成母羊依据表型值选择与依据综合育种值选择的结果差异  相似文献   
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