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1.
1防寒保暖哺乳仔猪对温度的一般要求是:初生,35℃1~3日龄,32℃~30℃,4~7日龄,30℃~28℃,15~30日龄,25℃~22℃,2~3月龄,以保持20℃为宜。1.1塑料暖棚法第一种方法是槽形棚法,以走廊式猪舍为例,从猪舍前缘连接运动场部分开始,沿墙顶加设拱形塑料棚,根据饲养规模,既可一圈一棚,也可多圈设一棚,将运动场扣在棚内;第二种方法是脊形棚法,将猪圈顶部和两侧各以木杆固定成脊形棚架,然后扣上薄膜,使整个猪圈置于棚内。无论采取槽形或脊形,在棚顶部都应留一个活动通气孔,用以调节温度,便于排出有害气体。1.2红外线灯增温法采用笼养仔猪,在仔猪…  相似文献   

2.
为躺卧区的初生仔猪提供适宜温度是保障其成活率的关键,但目前尚无仔猪躺卧区面积的统一标准。本研究选取3窝活仔数为12头的母猪分娩栏,进行一个完整哺乳周期的测量与记录。通过对仔猪在躺卧区的行为进行分析,得到仔猪趴卧面积公式A=0.027e~(0.234w),侧卧面积公式A=0.029e~(0.235w)(w为仔猪体重),并确定了不同日龄仔猪对躺卧区的利用率。结果发现断奶仔猪数为12头的仔猪躺卧区面积不应低于0.37m~2,为分娩栏内仔猪保温设施的供热面积提供了合理根据。  相似文献   

3.
1992年6—10月在合川市后备猪种场,选取长×长本的9窝90头杂种仔猪,按窝内分组法随机分为试验1组、试验2组和对照组,每组30头,各组平均初生重差异不显著(P>0.05)。试验仔猪3日龄内一律每  相似文献   

4.
母猪窝产仔均匀度相关性状是影响哺乳仔猪死亡率的因素之一。本研究对9 458头长白猪和13 317头大白母猪分娩数据进行分析发现,长白和大白猪初生窝内平均重变异度分别为17.9%和18.0%,初生窝内平均重标准差分别为262.6、257.6 g。研究表明,母猪品种、配种组合、母猪产活仔数、胎次、季节及母猪妊娠天数影响母猪窝产仔均匀度。初生窝内平均重标准差依次为大长杂繁(YL)长大杂繁(LY)长白纯繁(LL)大白纯繁(YY)(P0.05);随着产活仔数的增加,初生窝内平均重变异度和标准差显著升高(P0.05);初生窝内平均重标准差和初生窝内平均重变异度均是第1胎最低,随着胎龄而增加。本研究提示通过选择合适的品种、规范胎龄分布和有效的季节性管理措施可以改善猪群窝产仔均匀度。  相似文献   

5.
陈国宇 《养猪》2000,(3):34-35
养猪场的设计首先应根据所确定的工艺流程和技术参数 ,先计算出各猪舍猪栏的数量 ,随后才能合理地计算出每幢猪舍的建筑面积。笔者经过多年的实践积累和在日本两年的养猪技术学习 ,总结出一套猪舍猪栏数的快速计算方法 ,供养猪界同仁在设计猪场时参考。以饲养 1 0 0头基础母猪的猪场为例 ,进行各猪舍的猪栏数计算 ,其方法如下。1 分娩舍猪栏数分娩猪栏数 =年间分娩窝数×分娩舍饲养时间÷3 65母猪 1 0 0头 ,平均年产 2 3窝 ,全年计 2 3 0窝 ,分娩舍饲养时间为 4 2天。分娩猪栏数 =2 3 0× 4 2÷ 3 65=2 6 5,所以分娩舍应建 2 7个分娩栏。…  相似文献   

6.
我们在设计养猪场时 ,首先应根据已确定的工艺流程和技术参数 ,先要计算出来各类猪舍猪栏的数量 ,然后才能合理地计算出每栋猪舍的建筑面积。笔者经过多年的实践经验积累和在工厂化猪场多年咨询工作的体会 ,总结出各类猪舍猪栏数的快捷计算方法 ,供养猪界同仁在设计猪场时参考。现以饲养 10 0头基础母猪的猪场为例 ,进行各类猪舍的猪栏数计算 ,其方法如下。1 分娩舍猪栏数分娩舍猪栏数 =年间分娩窝数×分娩舍饲养时间÷ 36 5母猪 10 0头 ,平均年产 2 .2窝 ,全年产 2 2 0窝 ,分娩舍饲养42d ,具体划分为 :分娩前进舍天数 7d ,授乳时间 2 5…  相似文献   

7.
心肺活动和体温的变化是调节生理过程中的重要组成部分,因而常把心肺活动和体温的变动情况或差异来作为判断家畜的热调节能力和对气候适应性的指标。里岔黑猪是我国优良的地方猪种之一,具有较强的适应性,为进一步探讨其适应能力的大小,进行了本试验,通过测定在不同温度条件下,不同日龄里岔黑猪的体温、呼吸和心事,分析其适应性。1材料和方法1.1猪种来源和分组猪种来源于胶州里岔黑猪原种场,四窝共十二头;随机分成二组,每组六头,组间体重差异不显著。1·2测定项目和方法l·2·1于go、120’150、180日龄分别测量体温,连续三天在…  相似文献   

8.
本文介绍了最近荷兰和西德等国的猪舍结构。一、种猪场的猪舍构造和换气基准 1、容纳100头母猪的猪舍的一般要求: (1)仔猪4~5周龄断奶。 (2)综合猪舍内设分娩猪单元,内设4个区、断奶猪单元,内设5个区;或者设置分娩和断奶兼用猪单元,内分九区。 (3)猪舍中设置主通道和获得新鲜空气的间接进气口。 (4)供新鲜空气进入主通道的进气口,容积每1立米需截面积2平方厘米。从主通道进入其它猪舍的进气口,容积每1立方米需截面积1.5平方厘米。  相似文献   

9.
美国肯塔基大学的研究人员发现,猪舍内的环境温度可影响猪对日粮中赖氨酸水平的反应。该大学的T.S.Stahly和G.L.Cromwell最近进行了这方面的研究。两位学者作了三个试验,使用了72头个体喂养的猪。18窝仔猪中每窝四头(约克夏×汉普夏)阉公猪随机分配入四种日粮赖氨酸水平(0.50、0.65、0.80和0.95%),饲养于冷(50°F)或热(72.5°F)环境中。  相似文献   

10.
仔猪在出生和哺乳期间死亡是猪群生产效率下降的显而易见原因之一。本文提供了仔猪从出生到死亡之间体重变化的资料以及初生体重和窝仔数对断奶存活率的影响的资料。本研究包括569头断奶前死亡的仔猪,以及一项评价妊娠猪舍环境对母猪第2~4胎繁殖性能影响的试验中的1819头断奶仔猪。共有124窝约克夏母猪(Y)的仔猪和109窝约克夏×拉康比母猪(YL)的仔猪。父本均为Y公猪。妊娠110天时,将母猪关入  相似文献   

11.
The metabolic heat production of modern pigs has increased by an average of 16%, compared with sows of 30 years ago. Therefore, it is likely that temperature recommendations require updating to meet the needs of modern pigs. The objective of this study was to evaluate whether different reproductive stages of sows altered thermal preference and if current recommendations required updating. Twenty multiparous sows (3.4 ± 1.2 parity) in different reproductive stages (nonpregnant: n = 7; mid-gestation: 58.5 ± 5.68 d, n = 6; and late-gestation: 104.7 ± 2.8 d, n = 7) were tested. Thermal preference was individually tested, and sows could freely choose a temperature, using a thermal gradient between 10.4 and 30.5 °C. Sows were given 24 h to acclimate to the thermal apparatus. Before testing began, sows were given daily feed allotment and returned to the apparatus. Video from the 24-h test period was used to record sow behavior (time spent inactive), posture (upright and sternal and lateral lying), and location using instantaneous scan samples every 15 min. Data were analyzed using PROC MIXED procedure in SAS 9.4. A cubic regression model was used to calculate the sow’s most preferred temperature based on the location, or temperature, in which they spent the most time. The preference range was calculated using peak temperature preference ±SE for each sow. The reproductive stage altered where sows spent their time within the thermal gradient (P < 0.01). Late-gestation sows preferred cooler temperatures (14.0 °C) than mid-gestation (14.8 °C; P < 0.01) and nonpregnant sows (14.8 °C; P < 0.01). In summary, sow thermal preferences were within the lower half of the current recommended range (10 to 25 °C). This indicates that temperatures at the higher end of the recommended range could be uncomfortable to sows and that the thermal comfort zone of sows may be narrower than recommendations indicate.  相似文献   

12.
本试验设计并制作了一台固体传热的动物模型。试验中测得橡皮(传热介质)的导热系数均值为0.207Wm~(-1)℃~(-1),哈尔滨白猪瘦肉系初生仔猪的毛皮热阻均值为29.4Sm~(-1)。  相似文献   

13.
Thermal stress can result in productivity losses, morbidity, and mortality if proper management practices are not employed. A basic understanding of the relationship between animals and the thermal environment is crucial to assess the environment’s impact on livestock performance. Therefore, the study objective was to evaluate whether different early life thermal stressors (ELTS) altered the temperature preference of pigs later in life. Twelve sows and their litters were randomly exposed to 1 of 3 ELTS treatments from 7 to 9 d of age: early life heat stress (ELHS; cycling 32 to 38 °C; n = 4), early life cold stress (ELCS; 25.4±1.1 °C without heating lamp; n = 4), or early life thermoneutral (ELTN; 25.4±1.1 °C with a heating lamp; n = 4) conditions. From 10 to 20 d, (weaning) all piglets were exposed to ELTN conditions. At weaning, pigs were randomly assigned to groups of 4 of the same sex and ELTS treatment. Temperature preference, where pigs freely choose a temperature, was assessed in 21 groups (n = 7 groups per ELTS treatment) using 1 of 3 thermal gradient apparatuses (22 to 40 °C). Testing began at 26 ± 1.3 d of age to give pigs time to acclimate to solid food after weaning and 1 group per ELTS treatment were tested simultaneously in each apparatus. Pigs were given 24 h to acclimate followed by a 24-h testing period. Behavior (active and inactive), posture (upright, sternal, and lateral lying), and location were documented every 20 min using instantaneous scan samples. Preferred feeding temperature was determined by the latency to empty a feeder in each location. Data were analyzed using PROC MIXED in SAS 9.4. A cubic regression model was used to calculate the peak temperature preference of pigs based on the temperature pigs spent most of their time. The preference range was calculated using peak temperature preference ±SE for each ELTS treatment group. Early life thermal stress altered where pigs spent most of their time within the thermal gradient (P = 0.03) with ELTN pigs preferring cooler temperatures (peak preference of 23.8 °C) compared with their ELCS exposed counterparts (peak preference of 26.0 °C; P < 0.01). However, ELHS exposed pigs (peak preference of 25.6 °C) did not differ in their temperature preference compared with ELTN or ELCS exposed counterparts (P > 0.05). In summary, ELCS exposure altered pig temperature preference later in life indicating that ELTS can alter temperature preference in pigs.  相似文献   

14.
温度是影响植物种子萌发和出苗最重要的环境因子之一,研究植物种子萌发对温度的响应,对确定物种的适宜播种时期和预测田间出苗率等有着重要的意义。以10种荒漠植物:沙冬青、白沙蒿、沙打旺、中间锦鸡儿、柠条锦鸡儿、无芒隐子草、梭梭、杨柴、花棒和霸王种子为材料,在5~40 ℃范围设置了8个温度条件,测定种子萌发的动态变化,通过积温模型分析了供试植物种子萌发的温度三基点:萌发的基础温度(Tb)、适宜温度(To)、最高温度(Tc)以及萌发的温度时间值(θT)。结果表明:在参试物种阈值中,To以无芒隐子草最高,为33.7 ℃,其次是沙冬青为28.3 ℃,其他物种在17.4~24.9 ℃;Tb以沙打旺最低,为0.3 ℃,其次是梭梭为1.9 ℃,其他物种介于6.7~15.0 ℃;Tc以梭梭最高,为45.3 ℃,其次是无芒隐子草为43.9 ℃、沙打旺43.3 ℃、沙冬青39.7 ℃,其余物种在25.0~34.2 ℃;梭梭萌发温度范围最大,为1.9~45.3 ℃,而霸王最小,为15.0~30.0 ℃。供试物种在亚适温条件下,种子萌发的温度时间值从小到大依次为:沙冬青(79 ℃·d)、梭梭(94 ℃·d)、白沙蒿(114 ℃·d)、杨柴(127 ℃·d)、霸王(132 ℃·d)、花棒(177 ℃·d)、沙打旺(184 ℃·d)、中间锦鸡儿(217 ℃·d)、柠条锦鸡儿(302 ℃·d)、无芒隐子草(334 ℃·d)。  相似文献   

15.
方冲伟 《蜜蜂杂志》2022,42(2):10-12
结晶蜂蜜加热是蜂蜜完全液化最方便的方法,控温热处理可以安全有效地液化结晶蜂蜜。该研究在45℃、55℃和65℃的不同温度下加热液化不会影响蜂蜜对大肠杆菌和金黄色葡萄球菌的总体抑菌活性。实验结果为蜂蜜的解晶温度控制提供参考。  相似文献   

16.

Objective

To compare the thermal nociceptive thresholds (TNTs) of dogs from three working/sport breeds.

Study design

Experimental prospective study.

Animals

Thirty healthy adult dogs of mixed age, sex and reproductive status, 10 of each of three breeds: Harrier Hound, Greyhound and New Zealand Huntaway.

Methods

On one day of each week for 4 weeks, unrestrained dogs were tested six times. TNTs were measured using a remotely activated device comprising a thermode attached to the thoracic limb, controlled by a microprocessor attached to the animal. Latency to exhibit behaviour indicative of nociception after initiation of heating and the temperature of the thermode at the point of behavioural response were measured. Linear mixed-effects models were fitted to the data, with dog included as a random effect, initial thermode temperature as a covariate and day, week and breed as fixed effects.

Results

Initial thermode temperature significantly affected dogs’ latency to respond (p < 0.001). Breed had a significant effect on both latency to respond and response temperature. Huntaways took longer to respond than Harriers or Greyhounds. For example, when the initial thermode temperature was 30 °C, Huntaways took 39.0 seconds to respond compared with 35.8 seconds for Harriers and 36.8 seconds for Greyhounds. Huntaways also responded at higher temperatures (mean ± standard deviation: Huntaways 49.7 ± 1.3 °C, Harriers 48.4 ± 1.6 °C and Greyhounds 48.7 ± 1.6 °C).

Conclusions and clinical relevance

Huntaways appeared to be less sensitive to thermal pain than the other breeds. Such information could be used by researchers and clinicians to better understand the generalizability of data gathered from a specific breed to the wider canine population or to tailor more effective pharmacological approaches to pain management in dogs.  相似文献   

17.
万军  朱兴友  张洋 《北方蚕业》2012,33(2):12-15
近年来昆虫抗冻蛋白(AFPs)的研究取得了较快的发展。本文综述了昆虫抗冻蛋白的发现过程、结构特点、表达规律、抗冻机制及相关的昆虫基因工程简况。  相似文献   

18.
总结分析了国内外有关肉鸡早期热服习的研究文献,归纳了肉鸡机体的体温调节机能、甲状腺和肾上腺机能、抗氧化机能、机体内脏器官的发育、血液生理生化指标以及HSP70与机体抗逆机能的相关性,探讨早期热服习提高肉鸡后期耐热力的机理。  相似文献   

19.
从早期热习服的概念、耐热力的评价指标以及早期热习服的时机出发,总结与分析了早期热习服对肉鸡后期耐热力形成的影响规律,试图探索出早期热习服提高肉鸡后期耐热力的机理。  相似文献   

20.
猪舍不同围护结构夏季隔热效果研究   总被引:3,自引:0,他引:3       下载免费PDF全文
为了寻找夏季隔热效果较好的猪舍围护结构类型,对不同墙体、屋顶结构类型猪舍的东墙、屋顶、吊顶内表面温度、舍内外温度进行了试验研究。结果表明,试验期间,黏土瓦屋顶+聚苯板吊顶的猪舍和彩钢夹芯板屋顶+聚苯板吊顶猪舍的吊顶内表面温度最高值分别为33.6℃和36.2℃;黏土瓦屋顶上覆盖彩钢夹芯板猪舍和黏土瓦屋顶猪舍内表面温度最高值分别为33.5℃和40.9℃。黏土瓦屋顶+聚苯板吊顶、黏土瓦屋顶上覆盖彩钢夹芯板猪舍屋顶隔热设计符合要求。240mm厚黏土砖墙50mm聚苯板、240mm厚黏土砖墙、370mm厚黏土砖墙+70mm挤塑板、370mm厚黏土砖墙东墙内表面温度最高值分别为32.7℃、32.3℃、32.1℃和32.7℃,四种墙体均符合猪舍东墙夏季隔热设计要求。四种猪舍围护结构类型中,370mm厚黏土砖墙+70mm厚挤塑板墙体、瓦屋顶上覆盖彩钢夹芯板屋顶猪舍隔热效果最好。试验结果可为北京市规模化猪舍建筑改造提供参考。  相似文献   

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