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51.
Summary Three breeds of sheep, Brazilian Somali, Morada Nova and Santa Inês which are indigenous to hot tropical semi-arid north-east Brazil were studied for their early growth. There were large breed differences in size at birth, at the 86th day and at 6 months. The Santa Inês was the largest and the Brazilian Somali the smallest. The type of birth (single vs. multiple) had a profound effect on weight at virtually all stages of growth which was similar for male and female lambs. Sex effects tended to become significant at around the 86th day, female lambs slightly outweighing males but marked sex differences appeared around 6 months when males outweighed females. The 7-day variation in age of lambs when the weights were taken around the 15th day had a marked effect on weight and correction for age would be necessary in future studies. However, the 7-day variation in age around the 86th day and thereafter did not affect the weights. The birth weight and weights at the 15th, 86th and 112 days and at 6 months were significantly correlated.
Evaluacion De Razas Ovinas Durante Su Crecimiento En La Nordeste Tropical De Brasil
Resumen Se realizó una evaluación de crecimiento precoz de tres razas nativas, Somali Brasilera, Morada Nova, y Santa Inés, razas que habitan la parte nordeste tropical semiárida de Brasil. Se encontraron diferencias marcadas en tamaño al nacer, a los 86 días y a los 6 meses. La Santa Inés fué la más grande y la Somali Brasilera la más pequeña. El tipo de parto (simple-multiplo) tuvo un afecto marcado en el peso virtualmente en todos los estados de crecimiento, efecto que fué similar en hembras y machos. Los efectos de sexo comenzaron a ser significativos alrededor del día 86, lashembras pesaron un poco más que los machos, pero los machos pesaron significativamente más que las hembras alrededor de los 6 meses. Los 7 días de diferencia en edad, cuando los borregos se pesaron alreadedor de los 15 días, tuvieron un efecto marcado, teniendo que hacer correcciones en el futuro. Este efecto no se detectó cuando se pesaron a los 86 días y posteriormente. Los pesos al nacer y el peso a los 15, 86 y 112 días y a los 6 meses se correlacionaron significativamente.

Evaluation Des Facultés De Developpement Chez Diverses Races De Mouton Dans Le Nord Est Du Brésil
Résumé Trois troupeaux de moutons de races indigènes Somali Brésilien, Morada Nova et Santa Inès adaptées au climat tropical chaud semi-aride du Nord Est du Brésil ont été comparativement étudiés au niveau de leur croissance précoce. On a observé de grandes différences raciales de taille à la naissance, au 86e jour et à 6 mois. Les Santa Inès ont été les plus développés et les Somali brésiliens plus petits. Le type de naissance (gestation simple ou gestation multiple) a eu un effet considérable sur le poids à virtuellement tous les stades de développement, qui a été semblable pour les agneaux mâles et femelles. L'effet du sexe tend à devenir significatif aux alentours du 86e jour, les femelles devenant un peu plus légeres que les mâles aux environs du 6e mois, la différence entre les sexes est plus marquée lorsque les mâles deviennent plus lourds que les femelles. Des variations de 7 jours dans l'âge des agneaux lorsque les poids ont été pris vers le 15e jour ont eu une influence marquée sur les poids et des corrections relatives à l'âge seraient nécessaires lors d'études ultérieures. Quoiqu'il en soit cette variation de 7 jours dans l'âge n'affecte pas les poids lors des pesées au 86e jour ni après. Les poids de naissance et ceux relevés les 15e, 86e et 112 jours ainsi qu'à 6 mois ont des corrélations significatives.
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Data on 4112 Muzaffarnagari sheep, maintained at the Central Institute for Research on Goats, Makhdoom, Mathura, India, and recorded between 1976 and 1999, were analysed to study the growth-related traits and their genetic control. The average weights at birth, and at 12 months of age were 3.1±0.2 and 28.0±0.6 kg, respectively. The pre- and post-weaning average daily weight gains were 127.8±3.3 g and 49.4±1.6 g, and the associated growth efficiencies were 3.59±0.08 and 0.95±0.03. Significant differences associated with the year of lambing were observed in body weight, weight gain and efficiency in weight gain at different stages of growth. The lambs born in the dam's second parity were generally of heavier weight and higher daily weight gain than those born in other parities. Males were heavier and had a higher weight gain than females at almost all stages of growth and the differences tended to increase with age. Single-born lambs had a distinct advantage over those born in multiple births at all stages of growth. The heritabilities of all body weights, weight gains and efficiency in weight gains at different stages of growth were moderate (0.18–0.26), except for birth weight, which was of low heritability (0.068±0.01). The phenotypic and genetic correlations among the different body weights were positive and high, except for birth weight. The genetic correlation of the pre- and post-weaning average daily weight gains with body weights were high and positive.  相似文献   
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Tandon S  Mittal AK  Pant AK 《Fitoterapia》2008,79(4):283-286
Essential oils of Vitex trifolia and Vitex agnus-castus were evaluated against Vth instar larvae of Spilosoma obliqua, when applied topically on the dorsal side of mesothoracic region, for insect growth regulatory activity. This treatment caused extended larval period and pupal period, increase in larval mortality and adult deformity and decrease in adult emergence, fecundity of female and egg fertility of test insect.  相似文献   
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A regional survey was conducted in Nepal for antibody to Japanese encephalitis virus (JEV) in domestic animals. Sera from pigs, and limited numbers of ducks and horses were collected from 16 districts in 2002-2003 and subjected to three serological tests. Of 270 porcine sera tested by C-ELISA, 55% were found positive for the presence of antibodies against Japanese encephalitis virus. Additional testing for IgM antibody to JEV revealed less than 2% of C-ELISA positive sera had evidence of recent JEV infection. Plaque reduction neutralisation tests (PRNT) using JEV, Murray Valley encephalitis (MVEV) and Kunjin (KUNV) viruses implicated JEV as the flavivirus associated with the observed antibody response in most sero-positive pigs. However, eight porcine sera with predominant neutralising antibody for KUNV (an Australasian subtype of West Nile Virus) provided evidence for the circulation of West Nile virus in Nepal.  相似文献   
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Water, Air, & Soil Pollution - The important attributes of macrobenthic community structure viz., species composition and number, population density, biomass, and dominance and diversity...  相似文献   
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The concentrations and chemical composition of water-extractable P were compared in four soil types from NE Scotland. All sites were sampled during the early establishment phase of a spring barley (Hordeum vulgare) crop. The quantity of total soluble P extracted ranged from <2.0 to 10 mg P kg soil-1, of which up to 50% was classified as being organically associated. Sample fractionation showed that both orthophosphate inorganic P and organic P were associated with a wide molecular-size range of organic material. A strong positive correlation was readily apparent between P and the sum of Fe + Al in the fractionated samples. The extent of enzymatic hydrolysis of organic P varied between soil samples and the type of enzyme. Phytase consistently produced the greatest degree of hydrolysis.  相似文献   
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