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11.
The field experiments were conducted for two crop years of 1997?–?98 and 1998?–?99 at the Indian Agricultural Research Institute, New Delhi to study the effect of wheat, legume and legume enriched wheat residue (WR) on soil fertility under the rice-wheat cropping system. A rice-wheat cropping system without incorporation of residue depleted organic C over initial level by 0.061%, kjeldahl-N by 0.012%, available P by 0.7?kg ha???1 and available K by 36?kg ha???1, whereas incorporation of Sesbania green manure (SGM), mungbean residue (MBR), SGM?+?WR and MBR?+?WR increased organic C over the initial level by 0.071, 0.100, 0.163 and 0.133%, respectively, kjeldahl-N by 0.001, 0.004, 0.001 and 0.005% respectively, available P by 2.7, 5.0, 8.5 and 3.2?kg ha???1, respectively and available K by 35, 5, 92 and 12?kg ha???1, respectively in 2 years. As compared with no residue control, incorporation of WR increased organic C by 0.036?–?0.102%, kjeldahl-N by 0.002?–?0.007% and available K by 23?–?45?kg ha?1, whereas incorporation of SGM and MBR increased organic C by 0.082?–?0.132 and 0.103?–?0.161%, respectively, kjeldahl-N by 0.009?–?0.023 and 0.005?–?0.013%, respectively and available K by 5?–?71 and 4?–?45?kg ha???1, respectively. Incorporation of WR with SGM and MBR was more effective and increased organic C by 0.121?–?0.224 and 0.125?–?0.194%, respectively, kjeldahl-N by 0.005?–?0.029 and 0.010?–?0.021%, respectively and available K content by 23?–?128 and 11?–?116?kg ha???1. Nitrogen application to rice also increased organic C, kjeldahl-N, available P and available K content in soil and also increased effects of crop residues. Crop residues had no significant effect on available P content in soil. Incorporation of WR with SGM and MBR with adequate fertilizer-N is, thus, recommended for building up organic C, kjeldahl-N and available K content in soil.  相似文献   
12.
A field experiment was conducted during the kharif season of the crop year 2001 at the Indian Agricultural Research Institute, New Delhi, to study the comparative effects of organic and conventional farming on scented rice. Grain yield of rice increased significantly with increasing rate of fertilizer application only up to 60?kg N?+?13?kg P?+?17?kg K ha???1. The effect of 10 t ha???1 farmyard manure (FYM) was found to be similar to 60?kg N?+?13?kg P?+?17?kg K ha???1, whereas the effect of Sesbania green manuring (SGM) was similar to 120?kg N?+?26?kg P?+?34?kg K ha???1. Inoculation of BGA (Blue green algae) with FYM or SGM had no additional advantage over FYM or SGM alone. The highest yield (5.2 t/ha) of rice was obtained when FYM?+?SGM?+?BGA?+?PSB (Pseudomonas striata) were applied together. The yield obtained with this combination was significantly more than that obtained with 180?kg N?+?39?kg P?+?51?kg K ha???1. A similar trend was observed in N, P, and K uptake of rice. Inorganic nutrients had no significant effect on grain quality parameters like head rice recovery (HRR), kernel length (KL), kernel breadth (KB) and KL?:?KB ratio, whereas organic manures and biofertilizers resulted in an increase in HRR, KL and KL?:?KB ratio. A combination of FYM?+?SGM?+?BGA?+?PSB also resulted in highest organic C and available N content in soil and thus holds a promise for sustainable production.  相似文献   
13.
Trypanosomosis is a major impediment to livestock production and economic development in those areas of Africa where it is endemic. Although small ruminants appear to perform better than cattle in various agro-ecological zones, the importance of trypanosomosis has not been extensively investigated in these livestock. This study was designed to investigate the prevalence of trypanosomosis in sheep and goats in an endemic area and to evaluate the performance of different breeds under high tsetse challenge and the potential role of chemoprophylaxis in the control of the disease. The results showed that tsetse flies feed readily on small ruminants, and that these animals are susceptible to trypanosomosis. The Small East African goats acquired fewer infections than the Black Head Persian and Dorper sheep used in the study. In both sheep and goats, chemoprophylaxis with isometamidium chloride (Samorin, Rhone Merieux, Annecy, France) was protective, resulting in fewer infections and higher body weight gain. Trypanosomosis caused anaemia in both sheep and goats, and animals whose PCV fell below 15% rarely recovered, even with trypanocidal drug treatment. The peak transmission period was between 1 and 3 months after the peak tsetse fly density, which raises the possibility of effective strategic prophylaxis.  相似文献   
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15.
Placental and breastfeeding transfer of soy isoflavones are potential routes for animal and human exposure to phytoestrogens, and reproductive dysfunctions have been linked to early exposure to these compounds. So, the aim of this study was to investigate the effects of perinatal (intrauterine and lactational) exposure to soy‐containing diet and soy‐derived isoflavones on the reproductive parameters of male rabbits. For this purpose, 12 female rabbits were randomly assigned to receive: (1) a soy‐ and alfalfa‐free diet (control diet); (2) a soy‐ and alfalfa‐free diet supplemented with 10 mg/kg body wt/day of soy isoflavones; (3) a soy‐ and alfalfa‐free diet supplemented with 20 mg/kg body wt/day of soy isoflavones; and (4) a diet containing 18% of soy meal, throughout gestation and lactation. Weight and morphology of the reproductive organs of some of the male offspring were evaluated at weaning (between days 29 and 31). The remaining males were placed on the control diet from weaning to adulthood (gestational and lactational exposure only). Sexual behaviour, semen quality and reproductive organs’ morphology were evaluated after puberty. There were no significant differences in litter size and gestation duration between control and treatment groups. Perinatal exposure to soy‐containing diet and soy isoflavones did not alter testis, epididymides, proprostate and prostate weight and gross morphology. After puberty, sexual behaviour and semen parameters did not differ significantly from the control group. These results indicate that intrauterine and lactational exposure to soy‐containing diet and soy‐derived isoflavones may not adversely affect reproductive development and function of male rabbits.  相似文献   
16.
Soybean meal (SBM) is the most widely and expensive protein source used in the formulation of poultry diets; however, when the price of SBM increases, poultry nutritionists seek alternative sources that are more economical in formulating least‐cost rations. This research aimed to evaluate the effects of dietary air‐classified sunflower meal (SFM) on some productive parameters and plasma steroid hormones in laying hens. In this trial, 20‐week‐old laying hens (ISA Brown strain) in the early phase of production were randomly assigned to two groups and fed wheat middlings‐based diets containing soybean (135 g/kg; 48% CP) or air‐classified SFM (160 g/kg; 41% CP) as the main protein source. Laying performance, egg size and feed conversion ratio were evaluated for 10 week. Plasma steroid hormones (progesterone and oestradiol) in the hens were quantified weekly. Substituting SBM with air‐classified SFM did not change (p > 0.05) the hens' growth performance, whereas feed consumption and efficiency were positively influenced (p < 0.05) by SFM treatment. Egg production rate was improved in hens fed the SFM diet (p < 0.05), as well as the percentage of medium‐size eggs that was higher for SFM treatment (p < 0.05). Steroid hormones levels were affected by dietary treatment (p < 0.01). From our findings, it could be effective to include air‐classified SFM in early‐phase laying hen diets as an alternative protein source substituting SBM, without negative influence on productive performance and egg traits, reducing also the production costs.  相似文献   
17.
The objectives of this study were to determine the non‐specific aerobic and anaerobic bacterial causes of endometritis causing repeat breeding of cycling Iraqi buffalo cows at Nineveh province, validate diagnostic criteria for endometritis and to evaluate the treatment efficiency of using systemic or intra‐uterine infusion of antibiotics for the treatment of endometritis. Data were collected from 60 buffalo cows with history of repeat breeding in different herds. All buffaloes were subjected to detailed clinical examination including external inspection, vaginoscopy and transrectal palpation of the cervix, uterus and ovaries. Swabs for bacteriology and biopsies for histopathology were collected from the uterine lumen from each cow. Character, odour and estimation of polymorphonuclear cells (PMN) of the vaginal mucus were scored. Blood samples were collected from cows for creatine kinase (CK) and aspartate aminotransferase (AST) measurement. Treatment conducted using oxytetracycline with tylosin in local intrauterine infusion or systemically with hormonal treatment. The most pre‐disposing factor for uterine infection was retained placenta (13.3%). The most prevalent bacteria in uterine lumen were E. coli (23%), Archanobacterium pyogenes (13%) and Staphylococcus aureus (10%) were mostly isolated from buffaloes with repeat breeding. Vaginal mucus character score was associated with the bacterial growth density score. The difference in PMN was highly significant (p < 0.01) in animals with repeat breeding than control groups. In addition, PMNs was significantly (p < 0.01) correlated r = 0.894 with the character of vaginal discharge. High level of PMNs observed in buffaloes infected with A. pyogenes. Buffalo cows with endometritis had higher CK (321.47 ± 39.06 vs 162.01 ± 16.41 U/l) and AST (133.93 ± 12.43 vs 97.01 ± 6.86 U/l) activities (p < 0.05) than control‐heifers, but no significant difference was observed between buffalo cows with endometritis in CK (321.47 ± 39.06 vs 208.33 ± 5.84) and AST (133.93 ± 12.43 vs 156.17 ± 9.65) activities than control‐pluriparious. It could be concluded that A. pyogenes was the only non‐specific uterine pathogen directly associated with severe endometrial lesions. Vaginoscopy examination combined with palpation of uterus increase the accuracy of diagnosing endometritis and cytogenic examination of uterine discharge is more reliable method of establishing the presence or absence of uterine inflammation in buffalo cows. Animals with repeat breeding (endometritis) showed clinical cure and improved pregnancy in all treatment groups with no significant difference. The use of oestradiol in repeat breeder cases has no effect in improving neither clinical cure rate nor pregnancy rate.  相似文献   
18.
19.
The objectives of the present study were to determine the relationship between bacteriological findings, clinical signs and histopathological changes in postpartum metritis. Evaluation of the treatment efficiency of using systemic or intra‐uterine infusion of antibiotics with some hormonal preparations for the treatment of postpartum metritis. Data were collected from 50 buffalo cows with history of calving of more than 1 month. All buffaloes were subjected to detailed clinical examination including external inspection, vaginoscopy and transrectal palpation of the cervix, uterus and ovaries. Swabs for bacteriology and biopsies for histopathology were collected from uterine lumen from each buffalo included in the present study. Bacteria identified using API systems following aerobic and anaerobic cultures. Vaginal mucus scored for character, odour and estimation of polymorphonuclear cells (PMNs). Treatment conducted using oxytetracycline in local intrauterine infusion or systemically with hormonal treatment including prostaglandinF2α (PGF2α) and oestradiol benzoate. Results revealed that the most predisposing factor for postpartum uterine infection was retained placenta and toxic puerperal metritis. The most prevalent bacteria in uterine lumen were Escherichia coli, Archanobacterium pyogenes, Bacteroides fragilis and Fusobacterium necrophorum the most prevalent bacteria in buffaloes with postpartum metritis. A. pyogenes and F. necrophorum were an important pathogens causing severe uterine inflammation as found in histopathological examinations. Buffaloes with postpartum metritis showed good clinical cure when oxytetracycline injected systemically with PGF2α. Intrauterine infusion of oxytetracycline had no advantage for the treatment of uterine infection in buffalo cows with postpartum metritis. PGF2α improved clinical cure of buffaloes with postpartum metritis.  相似文献   
20.
不同氮素水平下气象因子对两种水稻热值影响的分析   总被引:6,自引:0,他引:6  
对两种水稻类型在不同氮素水平下植株的热值变化与气象因子关系进行了分析。结果表明,水稻热值随着生长发育的进程存在着动态变化。两种水稻的热值最低值出现在幼穗分化期,最大值出现在分蘖期或开花灌浆期。随着施氮水平的增高,水稻的热值也增加,表明水稻的热值是一个与水稻生长发育及外界环境因子密切相关的动态变化指标。无论氮素水平的高低,光照因子(总日照时数、平均日照时间)对两种水稻有负影响效应。温度日较差对热值有正影响效应,且具有较低的变异系数,雨量与雨日的正效应起修饰作用。最低温度对热值具负影响作用,表现出大的变异系数。实际测定早稻的平均热值为17058 J/g,晚稻为16978 J/g,说明早稻的热值要高于晚稻。气象因素分析表明对于早稻感温型品种来讲,温度效应对热值的影响可能要大于日照对于热值的影响效应,而温度和日照对晚稻的热值影响效应要大于降雨量的效应。  相似文献   
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