Supplementation of Slow‐Release Melatonin Improves Recovery of Ovarian Cyclicity and Conception in Summer Anoestrous Buffaloes (Bubalus bubalis)          下载免费PDF全文

A Kumar  S Mehrotra  G Singh  VP Maurya  K Narayanan  AS Mahla  RK Chaudhari  M Singh  YK Soni  BL Kumawat  SK Dabas  N Srivastava 《Reproduction in domestic animals》2016,51(1):10-17

The role of melatonin as a protective neurohormone against restoring cyclicity in summer anoestrous animals in photoperiod species has gained wider acceptance. This study was designed to uncover the evidence the slow‐release melatonin (MLT) has on initiation of ovarian cyclicity and conception rate (CR) in summer anoestrous buffaloes. Thus, buffaloes diagnosed as summer anoestrous (absence of overt signs of oestrus, concurrent rectal examination and radioimmunoassay for serum progesterone at 10 days interval) were grouped as untreated (Group I, sterilized corn oil, n = 8) and treated (Group II, single subcutaneous injection of MLT @18 mg/50 kg bwt in sterilized corn oil, n = 20). Animals treated and detected in oestrus were artificially inseminated (AI) followed by division into Group III (second dose of MLT on 5th day post‐AI, n = 8) and Group IV (no melatonin administration, n = 10). Blood samples were collected at 4 days interval for estimation of serum MLT, progesterone and oestrogen using radioimmunoassay kit. Mean oestrous induction rate (OIR), oestrous induction interval (OII), interoestrous interval (IOI) and CR were estimated. Compared to control, concentration of melatonin was significantly (p < 0.05) higher in treated group ranging from 14.34 ± 1.72 to 412.31 ± 14.47 pg/ml whereas other two hormones did not show any concentration difference. Melatonin‐administered buffaloes showed significantly (p < 0.05) higher (90%) OIR with OII of 18.06 ± 1.57 days. Results showed improvement in conception rate in buffaloes administered with post‐insemination melatonin. It can be concluded from the study that slow‐release melatonin supplementation restored cyclicity in summer anoestrous animals resulting in improvement in conception rate in buffaloes.  相似文献   

Human Attacks by Large Felid Carnivores in Captivity and in the Wild     

Suzanne M. Shepherd  Angela Mills  William H. Shoff 《The Forestry Chronicle》2014,25(2):220-230

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Nitrate leaching from reseeded pasture     

M.A. Shepherd  D.J. Hatch  S.C. Jarvis  A. Bhogal 《Soil Use and Management》2001,17(2):97-105

Abstract. Nitrate leaching and soil mineral N status under grassland were measured on three contrasting soils, spanning winters 1995/96, 1996/97 and 1997/98, in Western England. The soils investigated were a freely draining silty clay loam (Rosemaund), a well drained loam (IGER 1) and a poorly drained clay loam (IGER 2). The effects of reseeding (ploughing and resowing grass) at IGER 1 and IGER 2 in autumn 1995 or 1996 were compared with undisturbed pasture. Reseeding at Rosemaund, in autumns 1995 or 1996, or spring 1996 was compared with undisturbed pasture of 3 sward ages (2, 5, >50 years).
Nitrate-N leaching losses during the winter immediately following autumn reseeding ranged between 60 and 350 kg N ha^–1 in 1995/96, depending on soil type, sward management history and rainfall. Losses were much less in the following winter when treatments were repeated (10–107 kg N ha^–1).
Reseeding in spring had little effect on soil mineral N content or leaching losses in the following autumn, compared with undisturbed pasture. Similarly, leaching losses from autumn reseeds in the second winter after cultivation were the same as undisturbed pasture (1-19 kg N ha^–1). The effect of ploughing grassland for reseeding was relatively short-term, in contrast to the effect of repeated annual cultivation associated with arable rotations.  相似文献   

‘Objection’ mapping in determining group and individual concerns regarding genetic engineering     

L.J. Frewer  D. Hedderley  C. Howard  R. Shepherd 《Agriculture and Human Values》1997,14(1):67-79

Whilst there has been much debateregarding the importance of public acceptance ofgenetic engineering and its applications, there isevidence to indicate that objections to the technologyare likely to focus on specific applications of thetechnology, rather than genetic engineering per se.Thus it becomes important to examine the extent ofobjections associated with individual applications,rather than to assess public feeling regarding thetechnology overall. Survey data were collected from200 respondents regarding their objections to generalapplications of genetic engineering (where thetangible benefits were not obvious). Similar objectiondata were collected from 200 different respondents,who were presented with specific applications withmore obvious tangible benefits. Overall patterns ofobjection to different applications were identifiedusing a novel method of objection mapping, inconjunction with analysis of variance to identifyindividual differences in the samples. For generalapplications, the results indicate that mostrespondents object less to applications involvingplants and microorganisms than to those involvinganimals or human genetic material. Individualdifferences in objection focus on applicationsinvolving animals or human genetic material, withwomen and those who are very concerned with theenvironment having greatest objections to theseapplications. Individual differences tend to reducewhen specific applications are used as stimuli,although the focus of concern is still on applicationsinvolving animals and human genetic material. However,gender differences were not statistically significant,and those respondents who have high levels ofenvironmental concern are differentiated by increasedobjections to large-scale agricultural applications.It is argued that effective communication regardingthe technology should focus on specific applications,and address issues of environmental impact within thecontext of these applications, if the public is tomake an informed choice regarding their acceptance ofthe products of the technology.  相似文献   

Activities of ketone body utilising enzymes in tissues of fed and fasted sheep.     

G C Varnam  M K Jeacock  D A Shepherd 《Research in veterinary science》1978,24(1):124-125

The activities of 3-hydroxybutyrate dehydrogenase, 3-ketoacid CoA-transferase and acetyl-CoA acetyltransferase have been measured in the kidney, heart and brain of fed and four-day fasted ewes. The results indicate tha there is a decrease in the capacity of these organs to catabolise ketone bodies in fasting ketosis.  相似文献   

Inheritance of tolerance to zinc deficiency in barley     

Y. Genc    K. W. Shepherd    G. K. Mcdonald  R. D. Graham  J. Leon 《Plant Breeding》2003,122(3):283-284

Barley (Hordeum vulgare L.) is often grown on alkaline zinc (Zn)‐deficient soils where reductions in yield and grain quality are frequently reported. Currently, the use of Zn‐based fertilizer along with Zn‐deficiency‐tolerant genotypes is considered the most thorough approach for cropping the Zn‐deficient soils; however, developing or breeding genotypes with higher Zn efficiency requires a good understanding of the inheritance of tolerance to Zn deficiency. This study was conducted to determine genetic control of this trait in barley. Two parental cultivars ('Skiff, moderately tolerant; and ‘Forrest’, sensitive), 185 F₂ plants, and 48 F₂‐derived F₃ families from this cross were screened to determine inheritance of tolerance to Zn deficiency using a visual score of deficiency symptoms. The segregation ratios observed indicated that greater tolerance to Zn deficiency in ‘Skiff compared with ‘Forrest’ at the seedling stage is controlled by a single gene with no dominance. The results also indicate that visual scores are useful for genetic analysis of tolerance to Zn deficiency.  相似文献   

Pressure plate studies to determine how moisture affects access of bacterial-feeding nematodes to food in soil   总被引：4，自引：0，他引：4  

G.W. Yeates    J. L. Dando  & T. G. Shepherd 《European Journal of Soil Science》2002,53(3):355-365

Nematode activity in the soil depends on the presence of free water. We conducted pressure plate experiments to understand better how soil matric potential and structural degradation affect the population growth of three bacterial‐feeding nematodes (Cephalobus, Pristionchus, Rhabditis). We took undisturbed cores from six soils (sand, silt loam and silty clay loam with four management regimes), and removed all fauna from them. Ten or 30 nematodes were added, and pressures corresponding to soil matric potentials of ?10, ?33, ?50, ?100 or ?1500 kPa were applied for 35 days. The nematodes were then counted. Significant reproduction of all bacterial‐feeding nematodes occurred when the diameters of water‐filled pores were approximately 1 μm. This confirms observations using repacked soils and field manipulations. Only for Pristionchus did declining populations match the reduction in total soil porosity related to intensification of land use on the silty clay loam. We had not expected Cephalobus to have the fastest increase in population of the three nematodes in intact soil cores, and our evidence questions the relative importance given to the three nematode families in soil processes. The differing rates of population increase of the three nematodes in the various soils reflect both habitable pore space and trophic interactions. This suggests that the very diversity of nematode assemblages is crucial in the resilience of biological soil processes. That water‐filled pores as small as 1 μm provide suitable spaces for sizeable populations of bacterial‐feeding nematodes accords with the observed migration of infective juveniles of trichostrongylid nematodes and mermithids in water films on herbage. Our results imply that assessment of the role of nematodes in soil processes may be a key to the understanding of biological interactions in water films, and the selection pressures on nematode morphology.  相似文献   

Soil fertility in organic farming systems – fundamentally different?     

E.A. Stockdale  M.A. Shepherd  S. Fortune  S.P. Cuttle 《Soil Use and Management》2002,18(S1):301-308

Abstract. Soil fertility is defined as the ability of a soil to provide the conditions required for plant growth. It is a result of the physical, chemical and biological processes that act together to provide nutrients, water, aeration and stability to the plant, as well as freedom from any substances that may inhibit growth. Within this definition, it is useful to distinguish between those components of fertility which change relatively slowly, perhaps over the course of a rotation, or in some cases, decades, and the more immediate contribution from materials such as fertilizers and manures. The term 'inherent fertility' is used to describe these more stable characteristics, while recognising that they are, to a large extent, products of soil management. We conclude that, although nutrient management in organically managed soils is fundamentally different to soils managed conventionally, the underlying processes supporting soil fertility are not. The same nutrient cycling processes operate in organically farmed soils as those that are farmed conventionally although their relative importance and rates may differ. Nutrient pools in organically farmed soils are also essentially the same as in conventionally managed soils but, in the absence of regular fertilizer inputs, nutrient reserves in less-available pools will be of greater significance.  相似文献   

Nitrate leaching from a shallow limestone soil growing a five course combinable crop rotation: the effects of crop husbandry and nitrogen fertilizer rate on losses from the second complete rotation     

P.A. Johnson  M.A. Shepherd  D.J. Hatley  P.N. Smith 《Soil Use and Management》2002,18(1):68-76

Abstract. The field experiment tested the effects of three management systems on nitrate leaching losses from a five crop rotation on the Lincolnshire Limestone in Eastern England. The Standard system was similar to farming practice in the area. The Protective system integrated individual practices which were expected to decrease nitrate losses (e.g. cover crops, cultivation delay in autumn and reduced intensity, manipulation of drilling dates and, during the first few years of the first rotation, straw incorporation). The Intermediate system was a compromise between the two extremes. All crops were grown at full and half recommended nitrogen rates. This paper reports data from the second full rotation (years 6–10), thus enabling the medium-term effects of continued management practices to be investigated. Average annual nitrogen leaching losses at 49, 35 and 25 kg N ha^–1 for Standard, Intermediate and Protective systems, respectively, were significantly different. The respective flow-weighted average NO₃ concentrations were 167, 131 and 96 mg l^–1. Thus, adopting nitrate retentive practices through the rotation was able to substantially decrease losses. The Protective system was as effective as in the first full rotation, demonstrating that 10 years of such practices had not failed in the medium-term. However, continued minimal cultivation caused serious problems of weed build-up. The cost of weed control and yield loss caused by grass weeds made cereal production uneconomic in some years. Thus, rules for nitrate leaching control need to be tempered with practical and agronomic considerations. Also, few (if any) management techniques tested guaranteed that nitrate losses would be small in all years, as the interaction with winter weather, particularly rainfall, was of vital importance.  相似文献   

Controlling dog behaviour     

Shepherd K 《The Veterinary record》2011,169(5):132

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