近10年鹿放牧生态研究进展

从鹿的放牧笔为特点,季节动态、生物因素、非生物因素以及劳动生产因素对鹿放笑话地为的影响,鹿放牧对草地植被的影响等方面,总结近１０年来国内外在鹿放牧生态领域的研究进展,并对今后值得研究的方面提出建议。     

放牧对草地生态系统结构与功能影响的研究进展

放牧是草地生态系统最主要的利用方式之一，不同的草地类型、放牧强度、放牧家畜种类、草地利用方式以及气候变化等因素均会影响草地生态系统结构与功能。深入揭示放牧活动及气候变化对草地生态系统的影响机制对其可持续发展具有重要意义。本文系统综述了放牧对草地生态系统结构与功能的影响机制，并对该领域几个重要研究方向进行了展望，未来相关研究需重点关注的问题包括：(1)提升放牧草地生态系统中的空间耦合分析；(2)注重草地生态系统多功能性研究；(3)完善全球变化背景下的放牧地多因素嵌套试验；(4)开展不同种类放牧家畜混牧试验；(5)规范草地生态试验方法。以期为草地生态系统的适应性管理和可持续发展提供理论参考依据。     

内蒙古牧区牧户委托放牧行为及影响因素实证研究

以内蒙古两大牧区锡林郭勒盟和呼伦贝尔市为研究区域,以442户实地调查牧户数据为基础,运用描述统计分析方法和有序Logistic回归模型,对牧户委托放牧行为及其影响因素进行实证分析。研究结果显示,户主年龄、畜牧业收入占家庭总收入的比例、是否禁牧和单位面积载畜量对牧户委托放牧行为有显著正影响(P0.05),而放牧经验、家庭劳动力人数、家庭固定资产价值以及有无打草对牧户委托放牧行为有显著负影响(P0.05)。基于实证分析的结果,提出了规范委托放牧行为,完善委托放牧方式,实现草地有效管理的政策建议,以期在牧户草地承包权长久不变、经营权或使用权流转不畅现状下,为政府部门制定和完善草原牧区草地管理政策和制度提供决策依据。     

施肥和刈割处理模拟放牧对西北针茅生长的影响

放牧是天然草地最主要的利用方式,其对于草地的影响主要是采食、践踏和排泄作用.不同畜种具有不同的牧食行为,对于草地的影响也不同.为了研究牛羊混合放牧对于西北针茅(Stipa sareptana var.krylovii)草原建群种的影响,本研究设置了对照、添加牛粪+刈割(模拟牛单牧)、添加羊粪+不刈割(模拟羊单牧)、添加...     

不同草地利用方式对内蒙古典型草原群落特征及草地健康的影响

为科学评价不同利用方式对典型草原健康的影响,本研究以西乌珠穆沁旗典型草原为研究区,通过群落调查结合Condition-Vigor-Organization-Resilience (CVOR)草地健康评价模型,综合评价放牧刈割草地(MG)、夏季放牧草地(SG)、冬季放牧草地(WG)、禁牧刈割草地(MP) 4种不同利用方式对草地健康的影响。研究发现：1)冬季放牧草地群落平均高度显著低于其他利用方式(P <0.05),夏季放牧草地平均盖度、密度显著低于其他利用方式(P <0.05),放牧是影响群落形态特征的主要因素之一,夏季放牧草地Shannon-Wiener指数和Simpson指数显著低于其他利用方式(P <0.05)。放牧刈割提高了群落的的丰富度和均匀度。2)冬季放牧草地群落生物量和凋落物量显著低于其他利用方式。3)基于CVOR指数评价综合草地健康等级：MG> MP> WG> SG,放牧刈割草地综合草地健康指数最高(HCVOR=0.84),其余3种利用方式处于“不健康”状态。应适当加强对放牧刈割草地的利用,对其他3种利用方式进行因地制宜的草地管理措施,...     

高寒草甸放牧生态系统研究现状

综述了放牧强度对高寒草甸植物、动物和土壤的影响,说明放牧强度是影响家畜生产力、草场恢复力和稳定性的重要因素,也是影响土壤理化性质和土壤养分分布格局的关键因素;同时指出,高寒草地放牧系统受人为或气候等因素的影响而不断变化,影响的强度会改变整个系统的状态和变化趋势,即使是同一块草地,其负载能力和适宜放牧率(强度)也有所波动.因此,高寒草地放牧生态系统研究应以草场本身的条件和动态特征加以评价,应尽可能选择较多的气候和草场类型,应用动态规划和系统优化模型,对草地的持续生产和畜牧业的可持续发展进行动态模拟;建立草地放牧生态系统管理专家系统.     

草地放牧制度及评价

本文根据近期国外有关资料和刊物发表的关于草地放牧制度评价方面的论述及研究结果,论述了连续放牧与划区轮牧两种放牧制度对草地家畜增重、牧草生长、家畜营养摄入和家畜行为的影响。认为影响草地牧草生长及家畜表现各方面的并不是放牧制度本身,而与其载畜率及采用的放牧技术手段和放牧条件有关。     

Meta分析中国不同类型草地放牧强度对土壤氮素矿化作用的影响

氮是草地生产功能的重要限制因素,氮素矿化作用为草地肥力的重要指标.草地生态系统净氮矿化速率对放牧干扰存在不同的响应特征,本研究采用Meta分析方法,通过对中国草地已开展的32个有关放牧对草地矿化作用影响的试验结果进行整合分析.结果 表明:放牧轻微增加我国草地土壤净氮矿化速率,增幅约0.68％,平均效应值为0.01±0.13(置信区间为-0.24～0.25).放牧极显著增加了高寒草甸矿化作用(P＜0.05),平均效应值约为0.38±0.10.放牧降低了温性草原、温性荒漠和沼泽湿地(P＞0.05)土壤净氮矿化速率.放牧强度对平均效应值具有极显著影响(P＜0.0001),轻度和中度放牧提高氮素矿化速率分别为13.88％和5.12％,而重度放牧降低草地氮素矿化速率约9.42％.土壤湿度和海拔对平均效应值具有显著正效应影响(P＞0.05),分别可以解释14.30％和13.61％的效应值变异.轻度和中度放牧有利于提高我国草地生态系统氮素矿化作用和供给能力,可以作为草地生产管理的重要利用方式.暖湿化气候情景有助于提升草地生态系统氮素矿化作用和供给能力.     

不同放牧环境下绵羊牧食行为的比较研究

为了研究同品种绵羊在不同放牧环境下的牧食行为差异,在典型草原区沙质草地和高平原草地两种放牧环境下,对四品种双杂交杂种绵羊的牧食行为进行了观察.结果表明:不同放牧环境下绵羊的采食时间和游走时间占放牧时间的80%左右,放牧环境对采食行为有显著的影响.绵羊在沙质草地采食和游走时间占总放牧时间的66.54%和15.63%,在高平原草地为77.49%和7.79%.不同放牧环境下卧息、站立等时间存在显著差异.     

放牧对草地植物群落的影响

从放牧强度、放牧制度、家畜采食习性等方面综述了放牧对草地植物群落的影响.适宜的放牧强度可促进草地的健康发展,丰富草地的生物多样性;放牧制度在不同地区的应用有差别,合理的放牧制度有利于维持草地生态平衡和草地生产力的提高.     

马鹿夏季放牧对祁连山草原群落多样性的影响

祁连山草原是我国重要的生态安全屏障,素有“高原冰原水库”和“生命之源”之称,同时也是我国西北地区“江河源”、河西走廊水资源安全的战略基地。祁连山北坡高寒灌丛作为这个安全屏障的重要组成部分,对区域内畜牧业发展的贡献不可忽视。马鹿是祁连山草原重要的特色放牧家畜,目前关于马鹿放牧对高寒灌丛群落学过程的影响研究缺乏。本研究在祁连山中段北麓以甘肃马鹿-高寒灌丛放牧系统为研究对象,探讨了夏季马鹿的放牧强度和地形对高寒灌丛β和γ多样性的影响。结果表明:1) 阴坡和谷地放牧强度之间β多样性差异显著,谷地β多样性嵌套现象显著;2) 中度放牧促进γ多样性,地形间差异不显著。总体来讲,马鹿适度放牧显著提高了高寒灌丛草地的γ多样性。研究结果以期为祁连山草原的可持续放牧管理提供科学理论依据。     

Reduced Sheep Grazing and Biodiversity: A Novel Approach to Selecting and Measuring Biodiversity Indicators

Traditional upland livestock grazing is declining worldwide, leading to concerns about possible impacts on biodiversity. Although monitoring of protected areas often focuses on rare species, management changes also affect currently common species and vegetation structure. “Biodiversity” is a concept rather than a simple variable, and monitoring it requires indicators that are widely applicable and appropriate to context. This paper presents a novel knowledge-driven approach to developing a selection of biodiversity indicators that can then be rapidly and objectively measured within rangeland environments. Stakeholder and professional opinion on likely changes in biodiversity following reductions in sheep grazing was elicited using a workshop-based process. Potential variables suitable for use as biodiversity indicators were developed and professional opinion on their usefulness sought. A number of indicators were then tested in a natural experiment field study on the impact of reduced sheep grazing in Scotland. In the field study, red deer abundance appeared to increase where sheep grazing was reduced. It was therefore necessary to use estimates of both sheep and deer abundance as explanatory variables. In agreement with the professionals’ predictions, dwarf shrub abundance and vegetation height were greater where sheep grazing had been reduced, after taking into account differences in deer. In contrast to the professionals’ predictions, the field results showed rough grasses and dead material were less abundant where sheep had been reduced, with deer also having an impact on dead material. The professionals were unsure of the effects of reduced sheep grazing on vegetation mosaic structure; the field results suggested that reduced sheep grazing leads to a reduction in structural heterogeneity, but that deer had the greater impact in this case. Several other predictions showed nonsignificant differences in relation to reduced sheep grazing. The participatory method and some of the field methods presented are cost effective and widely applicable.     

日月山梅花鹿公鹿血清生理指标研究

对日月山养鹿场围栏放牧的10头梅花鹿公鹿的7项血清生理指标进行了测定,并与祁连白唇鹿、祁连马鹿、祁连梅花鹿的某些生理指标进行比较。结果表明,日月山梅花鹿血清总蛋白显著低于祁连白唇鹿、祁连马鹿及祁连梅花鹿(P<0.01);日月山梅花鹿血清无机磷显著低于祁连白唇鹿(P<0.01),其他血清生理指标无显著差异(P>0.05)。     

Impact of molybdenum on the copper status of red deer (Cervus elaphus)

AIM: To determine the effect of increasing molybdenum (Mo) intakes on serum and liver copper (Cu) concentrations and growth rates of grazing red deer (Cervus elaphus). METHODS: Molybdenum- and Cu-amended fertilisers were applied to six 1.1-ha paddocks in a 3 x 2 design. Three levels of Mo were applied on two paddocks at each level in mid April (designated Day 1); levels were: none (control), 0.5 (medium) and 1.0 (high) kg Mo/ha as sodium molybdate. In late May (Day 39), two levels of Cu (none and 3.0 kg Cu/ha, as copper sulphate) were applied to each of the three levels of Mo-treated paddocks. Pasture Mo, Cu and sulphur (S) concentrations were measured at about fortnightly intervals. In late June (Day 74), ten 6-month-old red deer hinds were placed on the six experimental pastures, and serum and liver Cu concentrations were monitored at about monthly intervals for 102 days. The hinds were weighed on four occasions during the trial. RESULTS: Mean pasture Mo concentrations on Day 56 were 2, 4.6 and 11.3 mg/kg dry matter (DM) for the untreated control, medium and high Mo-treated pastures, respectively. Pasture Cu concentration was 95 mg/kg DM on Day 59, 53 mg/kg DM on Day 90, and 9 mg/kg DM by Day 153. Mean S concentration in pasture was 3.3 (range 3.03-3.45) g/kg DM. Copper application to pasture had no significant effect on serum and liver Cu concentrations in deer so data were pooled within Mo treatment. Mean initial (Day 74) serum Cu concentration was 9.2 micromol/L. In the deer grazing the control Mo pasture, this increased to 10.3 micromol/L on Day 112, before decreasing to 6.4 micromol/L on Day 176. In deer grazing the medium and high Mo-treated pastures, mean serum Cu concentrations were 3.8 and 3.9 micromol/L, respectively, on Day 112, and 2.5 and 3.3 micromol/L, respectively, on Day 176. Mean initial (Day 74) liver Cu concentration was 131 micromol/kg fresh tissue. In the deer grazing the control Mo pasture, this declined to 120 and 52 micromol/kg on Days 112 and Day 176, respectively. In deer grazing the medium and high Mo-treated pastures, liver Cu concentrations decreased to 55 and 52 micromol/kg fresh tissue, respectively, on Day 112, and 21 and 20 micromol/kg fresh tissue, respectively, on Day 176. Mean serum and liver Cu concentrations were not significantly different between deer grazing the medium and high Mo-treated pastures, and were lower (serum p=0.003, liver p<0.001) in those groups than in deer grazing the untreated control pastures. No clinical signs of Cu deficiency associated with lameness were observed. Deer grazing pastures that had Mo concentrations >10 mg/kg DM had lower (p=0.002) growth rates (100 vs 130 g/day) than those on pastures containing <2.4 mg Mo/kg DM. CONCLUSION: Increasing pasture Mo concentrations from 2 mg/kg DM to > or =4.6 mg/kg DM significantly reduced serum and liver Cu concentrations in grazing deer. Reduced growth rate was observed at pasture Mo concentrations >10 mg/kg DM.     

Red urine from red deer grazed on pure red clover swards

Twenty-four red deer hinds with their calves were released on to a newly established pure red clover sward and, 2 days later, red staining of the tail, perineum and hocks was observed. This was presumed to be of urinary origin. Observation of micturition showed that when urine was passed, it was a normal straw colour but it turned scarlet-red about 1 hour after exposure to air. Midstream urine remained the normal colour when held under a pure nitrogen atmosphere immediately after micturition, but it turned red when held in air in the dark, suggesting that the colour change was due to an oxidative rather than a photosensitive reaction. All deer grazing red clover were affected but this did not occur in deer grazing ryegrass/white clover swards. No adverse effects were observed in the deer grazing the red clover, and calf growth was significantly higher than on ryegrass/white clover, suggesting that the red urine had no effect on health or productivity.

Blood and urine analyses showed no signs of haemolysis, haematuria or haemoglobinuria. Preliminary chemical analyses suggest that the compounds involved are not those found in the urine of sheep grazing oestrogenic clover. The nature of the compounds have yet to be determined.     

Red urine from red deer grazed on pure red clover swards

Twenty-four red deer hinds with their calves were released on to a newly established pure red clover sward and, 2 days later, red staining of the tail, perineum and hocks was observed. This was presumed to be of urinary origin. Observation of micturition showed that when urine was passed, it was a normal straw colour but it turned scarlet-red about 1 hour after exposure to air. Midstream urine remained the normal colour when held under a pure nitrogen atmosphere immediately after micturition, but it turned red when held in air in the dark, suggesting that the colour change was due to an oxidative rather than a photosensitive reaction. All deer grazing red clover were affected but this did not occur in deer grazing ryegrass/white clover swards. No adverse effects were observed in the deer grazing the red clover, and calf growth was significantly higher than on ryegrass/white clover, suggesting that the red urine had no effect on health or productivity. Blood and urine analyses showed no signs of haemolysis, haematuria or haemoglobinuria. Preliminary chemical analyses suggest that the compounds involved are not those found in the urine of sheep grazing oestrogenic clover. The nature of the compounds have yet to be determined.     

Impact of molybdenum on the copper status of red deer (Cervus elaphus)

AIM: To determine the effect of increasing molybdenum (Mo) intakes on serum and liver copper (Cu) concentrations and growth rates of grazing red deer (Cervus elaphus).

METHODS: Molybdenum- and Cu-amended fertilisers were applied to six 1.1-ha paddocks in a 3 × 2 design. Three levels of Mo were applied on two paddocks at each level in mid April (designated Day 1); levels were: none (control), 0.5 (medium) and 1.0 (high) kg Mo/ha as sodium molybdate. In late May (Day 39), two levels of Cu (none and 3.0 kg Cu/ha, as copper sulphate) were applied to each of the three levels of Mo-treated paddocks. Pasture Mo, Cu and sulphur (S) concentrations were measured at about fortnightly intervals. In late June (Day 74), ten 6-month-old red deer hinds were placed on the six experimental pastures, and serum and liver Cu concentrations were monitored at about monthly intervals for 102 days. The hinds were weighed on four occasions during the trial.

RESULTS: Mean pasture Mo concentrations on Day 56 were 2, 4.6 and 11.3 mg/kg dry matter (DM) for the untreated control, medium and high Mo-treated pastures, respectively. Pasture Cu concentration was 95 mg/kg DM on Day 59, 53 mg/kg DM on Day 90, and 9 mg/kg DM by Day 153. Mean S concentration in pasture was 3.3 (range 3.03–3.45) g/kg DM. Copper application to pasture had no significant effect on serum and liver Cu concentrations in deer so data were pooled within Mo treatment. Mean initial (Day 74) serum Cu concentration was 9.2 µmol/L. In the deer grazing the control Mo pasture, this increased to 10.3 µmol/L on Day 112, before decreasing to 6.4 µmol/L on Day 176. In deer grazing the medium and high Mo-treated pastures, mean serum Cu concentrations were 3.8 and 3.9 µmol/L, respectively, on Day 112, and 2.5 and 3.3 µmol/L, respectively, on Day 176. Mean initial (Day 74) liver Cu concentration was 131 µmol/kg fresh tissue. In the deer grazing the control Mo pasture, this declined to 120 and 52 µmol/kg on Days 112 and Day 176, respectively. In deer grazing the medium and high Motreated pastures, liver Cu concentrations decreased to 55 and 52 µmol/kg fresh tissue, respectively, on Day 112, and 21 and 20 µmol/kg fresh tissue, respectively, on Day 176. Mean serum and liver Cu concentrations were not significantly different between deer grazing the medium and high Mo-treated pastures, and were lower (serum p=0.003, liver p<0.001) in those groups than in deer grazing the untreated control pastures. No clinical signs of Cu deficiency associated with lameness were observed. Deer grazing pastures that had Mo concentrations >10 mg/kg DM had lower (p=0.002) growth rates (100 vs 130 g/day) than those on pastures containing <2.4 mg Mo/kg DM.

CONCLUSION: Increasing pasture Mo concentrations from 2 mg/kg DM to ≥4.6 mg/kg DM significantly reduced serum and liver Cu concentrations in grazing deer. Reduced growth rate was observed at pasture Mo concentrations >10 mg/kg DM.     

Chemical composition, palatability and physical characteristics of venison from farmed deer

The quality of venison from farmed deer were evaluated based on chemical composition, palatability scores, W-B shear force, ultimate pH, and color. The samples of venison were derived from javan rusa ( Cervus timorensis russa ), moluccan rusa ( Cervus timorensis moluccensis ), sambar ( Cervus unicolor brookei ), fallow ( Dama dama ) and imported red deer ( Cervus elaphus ). Moluccan rusa and red deer were fed grass. Javan rusa, sambar and fallow deer were fed concentrate. The venison obtained from grazing deer (grass-fed) gave higher moisture content (75.3%) than concentrate-fed or confinement-raised deer (74.4%) and imported venison (70.62%). Fat content in venison shows some differences between muscles and species. The concentrate-fed animals had a higher ( P  < 0.05) fat content in the venison than the grazing deer. Temperate deer (fallow and red deer) showed higher ( P  < 0.05) fat content than tropical deer (rusa and sambar deer). Venison obtained from concentrate-fed deer showed normal ultimate pH values (pH ≤ 6.0) and more reddish in color than grass-fed deer. The concentrate-fed venison produced slightly higher ( P  > 0.05) palatability scores than grass-fed venison. Feeding regimens (grass-fed vs. concentrate-fed) significantly ( P  < 0.05) influenced fat composition in the venison of farmed deer in this study.     

Effects of grazing undrenched weaner deer on chicory or perennial ryegrass/white clover pasture on the viability of gastrointestinal nematodes and lungworms

This study determined the in vitro effects on the viability of internal parasites of grazing undrenched weaner deer on either chicory (Cichorium intybus) or perennial ryegrass (Lolium perenne)/white clover (Trifolium repens) pasture. One experiment investigated the hatching and development of gastrointestinal nematode eggs and larvae, and the development and motility of L1 lungworm (Dictyocaulus eckerti) larvae, and a second experiment used larval migration inhibition assays to test the viability of L1 lungworm larvae extracted from the faeces of weaner deer grazed on either chicory or pasture when they were incubated with rumen and abomasal fluids from fistulated deer also grazing on chicory or pasture. The incubations were undertaken with and without added condensed tannins purified from chicory and with or without polyethylene glycol (PEG) to bind the tannins. Chicory had no effect on the hatching and development of gastrointestinal nematode eggs and larvae. Grazing chicory reduced the number of lungworm larvae developing to the L3 stage, and L1 lungworm larvae from the faeces of chicory-grazed deer were less viable in rumen and abomasal fluid than larvae from pasture-grazed animals. Abomasal fluid was significantly (P < 0.001) less inhibitory to the migration of L1 lungworms than rumen fluid. When the larvae were incubated in rumen and abomasal fluids from chicory-grazed deer, their passage through sieves was significantly (P < 0.001) reduced in comparison with when they were incubated in the fluids from pasture-grazed deer Adding condensed tannins to rumen fluid increased the inhibition of the migration of L1 lungworm larvae but PEG removed this inhibition; this effect was not observed with abomasal fluid.