塔秀地区藏羊放牧育肥出栏适宜时期的研究

对塔秀地区不同类别的3组藏系绵羊,在60天的放牧育肥期内进行各旬增重率的测定,得出该地区绵羊后期放牧育肥的适宜时期为8月末至10月上旬。其中10月龄当年羯羔羊组在40天有效育肥期内的增重和增重率达到5·72kg和26·38%,分别比2岁以上的成年羯羊组高1·93kg和17·81百分点;淘汰母羊前期由于哺乳、复壮推迟,但在后期40天放牧育肥中,绝对增重量达到6·50kg,增重率高于2岁羯羊6·37百分点,仅低于当年羯羔羊组9·56百分点,表现了很强的补偿功能。     

高寒牧区藏羊放牧育肥出栏适宜时期的研究

对贵南县塔秀地区不同类别的3组藏系绵羊，在60 d的放牧育肥期内进行各组增重率的测定，得出该地区绵羊后期放牧育肥的适宜时期为8月末~10月上旬。其中10月龄当年羯羔羊组在40 d有效育肥期内的增重和增重率达到5.72 kg和26.38%，分别比2岁以上的成年羯羊组高1.93 kg和17.81%；淘汰母羊在40 d放牧育肥中，绝对增重量达到6.50 kg，增重率高于2岁羯羊6.37%，仅低于当年羯羔羊组9.56%，表现了很强的补偿功能。     

“畜大壮”对农区放牧绵羊的增重效果

为探索“畜大壮”对农区放牧绵羊的增重效果，于１９９４年８月１日至１０月２０日进行８０天的“畜大壮”增重试验。试验结果：在放牧条件下，试验组羊平均增重８．８ｋｇ，较对照组羊多增重５．２ｋｇ，增重率提高１７．５１个百分点，平均胴体重较对照组多２．４１ｋｇ，每只羊增加纯收入３８．６元。     

绵羊快速育肥素增重试验

绵羊快速育肥素为一种“四代”神经调控型增重素，是目前世界上少数国家推广应用的一种新型廉价，高效无毒增重素。１９９０年为实施阿勒泰“百万肉羊丰收项目”，特进行本试验，于１０月８日至１０月２７日在哈巴河县加依勒玛乡，随机组合１４４只阿勒泰绵羔羊进行了秋季一茬苜蓿野外放牧快速育肥试验。其中１００只为给药组（育肥素以下简称药组），４４只为不给药组即对照组，结果证明，给药组每日１ｇ／５ｋｇ体重连续给药２０天     

短花针茅草原五个载畜率水平绵羊活重变化规律

在内蒙古高原短花针茅荒漠草原采用了５个不同载畜率水平进行的绵羊放牧试验结果表明，绵羊活重均以１０月份为最大，中等载畜率有利于棉羊生产；随着载畜率增大，单位面积的绵羊增重逐渐增加，单个绵羊的增重逐渐减少，两者的交点为绵羊生产的适宜载畜率，即每半年２．２只羊／ｈｍ＾２。     

应用牛羊增肉剂提高绵羊增重效果试验

应用牛羊增肉剂给放牧绵羊做耳部皮下埋植观察增重效果，结果表明，试验组４５天平均增重９ｋｇ对照组增重７．３ｋｇ，试验组比对照组多增重１．７ｋｇ，提高增重２３．２８％，增重效果明显（Ｐ〈０．０１）。     

青海湖地区绵羊Na,Se缺乏的研究分析

青海湖地区夏季放牧绵羊唾液Ｎａ：Ｋ＝３．９－５．３：１,粪Ｎａ含量５１０－６７０ｍｇ／ｋｇＤＭ。青海省河卡种羊场绵羊血浆Ｓｅ大部分季节在０．１０－０．１４μｍｏｌ／Ｌ,粪Ｓｅ含量为０．０２４－０．０７６ｍｇ／ｋｇＤＭ。结果表明青海湖地区绵羊缺乏Ｎａ、Ｓｅ严重。     

绵羊放牧育肥在草原畜牧业生产中的地位和作用

本文所论述的“绵羊放牧育肥”，是指通过合理的利用季节草场，或辅以其它配套技术，使供肉用的羊只获得高于平常放牧增重的一种饲养方式，其目的是使育肥绵羊在较短时间内达到屠宰体重，从而缩短饲养周期，提高出栏率，降低羯羊在羊群中的比重，提高草原养羊业的经济效益...     

云南48—50支半细毛羊产肉性能及肉品质的研究

采取昼夜放牧与放牧补饲相结合两种饲养方法，对云南４８—５０支半细毛羊育成羊进行育肥试验和产肉性能研究。结果表明，７月龄是育成羊增重高峰期，放牧组、补饲组该月平均日增重达到１７４．０７ｇ和２０１．０２ｇ；在１５０ｄ（５～１０月龄）育肥期中平均日增重分别为１１８．６７ｇ和１４１．６０ｇ（Ｐ＜０．０１）；１０月龄体重分别达到４２．２５ｋｇ和４４．７４ｋｇ，胴体重分别为１９．８ｋｇ和２１．５４ｋｇ（Ｐ＜０．０５），均达到国内上等羔羊肉胴体肥度分等标准。屠宰测定和肉品分析结果表明，云南半细毛羊具有产肉性能好、羊肉品质高的优点。该试验还证明，在人工草地条件下，采用昼夜放牧方式可以达到育肥的目的。     

芦白2号系猪系统选育研究

芦白２号系猪经过５个世代的选育，各项性能指标均已达到或超过设计指标。总产仔数１２．２５头，６０天育成头数９．９２５头。２０天窝重４１．３３ｋｇ，６０天窝重１９７．１ｋｇ，育肥期平均增重５８３．３ｇ，达９０ｋｇ体重的平均日龄１８０．９天，每ｋｇ增重耗料３．４ｋｇ，瘦肉率５８．６５％。与杜洛克猪杂交，育肥期平均日增重６７３．４ｇ，达９０ｋｇ体重平均日龄１７０．３天，每ｋｇ增重耗料３．２７ｋｇ，瘦肉率６     

高寒牧区牦牛育肥试验研究

试验结果表明 :天然草地不同牧草利用率下 ,牧草利用率为 3 0 %的绝对增重、相对增重和日增重比 5 0 %和 70 %的分别高 2 2kg和 8 1kg、2 3 4%和 8 5 1%、0 0 2kg和 0 0 7kg ,各处理间差异不显著 (P >0 0 5 ) ,但处理内不同放牧期间差异极显著 (P <0 0 1) ;天然草地、人工草地上不同年龄组条件下 ,天然草地上绝对增重和日增重分别高于人工草地上的 ,0 5岁犊牛组的相对增重高于对应的 1 5岁犊牛组 ,日增重各处理间差异不显著 (P >0 0 5 ) ,但处理内不同放牧期牦牛日增重差异极显著 (P <0 0 1) ;在暖棚舍饲条件下 ,高精料组 (第一组 )的绝对增重、相对增重和平均日增重分别比低精料组 (第二组 )和对照组高 5 9kg、4 94%、0 9kg和 3 1 44kg、2 6 5 9%、0 49kg ,低精料组 (第二组 )比对照组高 2 5 5 4kg、2 1 65 %和 0 4kg ,两处理之间同一放牧期牦牛的日增重差异极显著 (P <0 0 1) ,处理内不同放牧期牦牛的日增重差异显著 (P <0 0 5 )。     

Effects of rate of gain during winter on subsequent grazing and finishing performance

Sixty mixed British breed yearling steers (237 kg) were used each year for 2 yr to study the effects of rate of gain during the winter on subsequent pasture and finishing performance. Winter gains of .28, .38 and .50 kg/d (P less than .05) were established for the low, medium and high gain treatments, respectively. Daily gain of steers on pasture was reduced (P less than .01) 81 g for each 100-g increase in winter daily gain. No differences in BW were observed among the treatment groups after grazing summer pasture. Wintering performance did not affect finishing performance. Daily gains during the finishing period increased slightly as pasture gain decreased due to increased feed intake, but efficiency was not altered. These data suggest that within this range of ADG during the winter and under the conditions of this study, it was not beneficial to winter cattle for an ADG more than .28 kg/d.     

大武地区青海草地早熟禾人工草地生长动态研究

对青海草地早熟禾人工草地生育期、盖度、高度和地上植物量年动态和4龄人工草地的季节动态进行了研究,结果表明：青海草地早熟禾生育期为134d,生育期到第2年以后趋于稳定;盖度,高度和地上植物量年动态曲线呈倒“V”字型,地上植物量和盖度在2龄时达到了顶峰,分别为626．5g／m^2和94．7％;高度在3龄时达到最大,为74cm,然后逐年下降;4龄青海草地早熟禾盖度,高度和地上植物量的季节动态曲线呈“单峰”型,盖度和高度在8月下旬达到最大值,分别为88．3％和70．6cm,地上植物量干重的最大值为546．2g／m^2,出现在8月上旬。     

Long-term supplementation of lasalocid-sodium for beef bulls during grazing and subsequent finishing period

117 white-red beef bulls were involved to investigate the effect of lasalocid-sodium when fed either during the grazing period, or the finishing period, or during both subsequent periods. The ionophore was fed at 250 mg daily per head incorporated in 1 kg dry sugar beet pulp on pasture and at 65 mg per kg concentrate afterwards (corresponding with 27 ppm in the ration DM). The finishing diet consisted of maize silage ad libitum and 0.75 kg concentrate per 100 kg liveweight per day. On pasture lasalocid significantly increased daily gain form 0.6 to more than 0.7 kg, without affecting the grazed area per animal. During the finishing period growth rate was only slightly affected by lasalocid, but feed intake was reduced (P less than 0.05) and feed conversion improved (P less than 0.05). Feeding lasalocid permanently for more than 400 days did not reduce these positive effects. Cumulative daily gain, total feed intake per head and feed conversion were 1.12 kg, 2176 kg dry matter (DM) and 4.70 kg DM. These figures amounted to 1.05 kg, 2283 kg DM and 5.16 kg DM when no lasalocid was fed; 1.06 kg, 2141 kg DM and 4.87 kg DM when lasalocid was only fed during the finishing period and 1.09 kg, 2246 DM and 4.99 kg DM when lasalocid was only fed during the grazing period. Daily gains of 1.05 and 1.06 kg were significantly lower (P less than 0.05) than 1.12 kg. Most carcass data were unaffected, except fatness. The permanent feeding of lasalocid increased carcass fatness, mainly as the result of a higher final weight.     

云南中海拔地区改良草地生态环境研究报告

[目的]通过改良草地生态环境的试验研究,旨在为合理、持续利用本地区草地提供理论依据。[方法]对云南中海拔地区的昆明小哨1996年建植的改良草地开展了除杂、补播、施维持肥料和放牧控制等方法。[结果]改良草地四年平均干物质产量5 368.84±624.25kg/hm2,载畜量为0.83hm2饲养1头西门塔尔牛;在全放牧条件下,西门塔尔牛的公母牛平均体重初生45.25kg,6月龄245.70kg,12月龄325.03kg,18月龄405.61kg,24月龄465.63kg,36月龄604.33kg,成年793.07kg。群体繁殖成活率85.19%。[结论]改良草地生态平衡可持续利用的关键在于每年施用维持肥料、适时除杂并补播和放牧控制。     

Effects of winter stocker growth rate and finishing system on: I. Animal performance and carcass characteristics

Angus-crossbred steers (n = 216) were used in a 3-yr study to assess the effects of winter stocker growth rate and finishing system on finishing performance and carcass characteristics. During winter months (December to April) steers were randomly allotted to 3 stocker growth rates: low (0.23 kg x d(-1)), medium (0.45 kg x d(-1)), or high (0.68 kg x d(-1)). Upon completion of the winter phase, steers were randomly allotted within each stocker treatment to a corn silage-concentrate or pasture finishing system. All steers regardless of finishing treatment were finished to an equal-time endpoint to eliminate confounding of treatments with animal age or seasonal factors. Upon completion of the finishing period, steers were slaughtered in 2 groups (one-half of pasture and one-half of feedlot cattle each time) and carcass data were collected. Winter data were analyzed as a completely randomized design, with winter treatment, pen replicate, year, and the winter x year interaction in the model. Finishing performance and carcass data were analyzed in a split-plot design with finishing system in the whole plot, and winter growth rate and winter x finish in the split-plot. Winter treatment mean within finishing replication was the experimental unit, and year was considered a random effect. Winter stocker phase treatments resulted in differences (P < 0.001) in final BW, ADG, and ultrasound LM area between all treatments for that phase. Pasture-finished cattle had lower (P < 0.001) final BW, ADG, HCW, LM area, fat thickness, KPH, dressing percent, USDA yield grade, and USDA quality grade. Winter stocker treatment influenced (P < 0.05) final BW and HCW, with low and medium being less than high. Steers with low stocker gain had greater (P < 0.05) finishing ADG. Dressing percent was greater (P < 0.001) for high than low, and USDA quality grade was greater (P < 0.05) for high than low and medium. Carcass LM area, fat thickness, KPH, and USDA yield grade were not influenced (P > 0.05) by winter rate of gain. Cattle on low during winter exhibited compensatory gain during finishing but were unable to catch the high group regarding BW or HCW. The USDA quality grade was greater for high than low or medium. Animal performance during the winter stocker period clearly impacts finishing performance, carcass quality and beef production in both pasture- and feedlot-finishing systems, when cattle were finished to an equal-time endpoint.     

Meat quality of fully or partly outdoor reared pigs in organic production

Abstract

Outdoor production on pasture is considered an option in organic pig production. The aim of the present trial was to study the influence of feeding strategies combining outdoor and indoor rearing on pig meat quality. The experiment was carried out with 245 pigs in 5 replicates, and commenced following weaning at day 52. Five treatments were compared: 1) pigs fed ad libitum and reared indoors with access to an outdoor concrete area (In-A); 2) pigs fed restrictively on pasture until 40 kg body weight and then kept indoors with access to an outdoor concrete area and fed ad libitum until slaughter (In-40A); 3) pigs fed restrictively on pasture until 80 kg body weight and then kept indoors with access to an outdoor concrete area and fed ad libitum until slaughter (In-80A); 4) pigs reared on pasture and fed restrictively during the whole period of growth (Out-R); and 5) pigs reared on pasture and fed ad libitum during the whole period of growth (Out-A). All pigs had free access to roughage (clover-grass silage/fresh clover grass). Restrictive feeding in the weight range from weaning to 40 kg body weight (In-40A) resulted in a reduced daily gain; however, following transfer to indoor facilities and ad libitum feeding these pigs compensated in growth and the overall daily gain did not differ from the In-A control pigs. Pigs fed restrictively from weaning to 80 kg body weight were unable to compensate completely following transfer to indoor facilities. Out-R pigs had the lowest overall daily gain, while In-A pigs and Out-A pigs had similar daily gain. Meat quality assessments were performed on longissimus dorsi (LD) samples from a subsample of 100 pigs (2 castrates and 2 female pigs from each treatment in each replicate). Compared to meat from either ad libitum treatments (In-A and Out-A), meat from Out-R and In-80A pigs was less red due to a lower pigmentation, and had a higher ratio of polyunsaturated:saturated fatty acids. In addition, Out-R female pigs had numerically (6–10 Newton) higher shear force than In-A and Out-A. Treatments did not affect the concentration of α-tocopherol of meat. Introducing a finishing period with free access to concentrates following 40 kg body weight until slaughter prevented the deterioration in meat quality. However, a finishing period following 80 kg body weight was not sufficient. In conclusion, ad libitum feeding in the organic production system gave superior meat quality compared to a restrictive feeding strategy. However, including a finishing period indoors with ad libitum feeding of concentrates may prevent the detrimental effect of restrictive feeding on meat quality.     

Comparative studies on growth traits of Sanga and Friesian-Sanga crossbred calves raised on natural pasture on the Accra Plains of Ghana

Data collected from 1993 to 2006 at the Animal Research Institute of Ghana was used to compare the performance of Sanga and Friesian-Sanga crossbred calves on natural pasture. Performance traits analyzed were birth weight (BWT), weaning weight adjusted to 210 days (WW7), preweaning average daily gain to 210 days (ADG 1), weight at 12 months adjusted to 365 days (W12), weight at 18 months adjusted to 540 days (W18) and postweaning average daily gain (ADG 2, from weaning to 540 days). Effects in the model describing these traits were breed, season, sex and first-order interactions between these effects. With the exception of heavier birth weight of Friesian-Sanga crossbred calves (19.98 kg vs. 19.18 kg), body weights of Sangas at weaning, 12 months and 18 months exceeded those of the Friesian-Sanga crossbred calves by 3.76 kg, 35.06 kg and 46.24 kg respectively. The Sangas were also superior in preweaning average daily gain (0.35 kg/day vs. 0.26 kg/day) and postweaning average daily gain (0.28 kg/day vs. 0.21 kg/day). There was a tendency of increasing weight difference between the two breeds with advancing age. It was suggested that improved nutrition such as supplementary feeding would be necessary for crossbreds to express their potential for growth.     

盘江黄牛育肥效果分析

选择健康无病、体格相近，不同年龄的盘江黄牛24头平均分为4组，其中2岁牛2个组(A、B组)，成年牛2个组(C、D组)，随机将4组牛分为高精料喂量组和低精料喂量组，以研究不同年龄盘江黄牛在育肥过程中给以不同精料日喂量时，其增重能力及育肥效益试验结果，在同喂高精料日粮状况下，2岁牛平均日增重显著低于成年牛日增重(P＜0．05)；在日粮精料量不同时，高精料喂量组牛的增重速度显著高于低精料喂量组(P＜0．05)。表明，牛的采食能力和饲料营养水平是影响肉牛增重的重要因素，日粮的精料喂量也在一定程度上决定肉牛的增重速度。