五龄蚕起眠到饷食时间长短对其摄食量与经济性状的影响

为了进一步探讨不同饷食时刻对蚕儿产茧效应的影响 ,以同一箔蚕为材料 ,分别在五龄起眠后 2 h、4 h、6 h……饷食 ,调查饷食后 1 8h小时内食下量及近似消化量 ;饲育老熟后调查有关成绩。结果表明 ,起蚕过迟饷食其产量低 ,茧质差。综合各项成绩 ,以五龄起眠后 1 0～ 2 0 h为最适宜的饷食期     

家蚕止桑、饷食时间的研究 Ⅱ.家蚕止桑、饷食时间与生长发育和代谢的关系

探讨了小蚕期止桑、饷食时间与大蚕期生长发育和代谢的关系,发现一至三眠迟饷食12小时,一至二眠或一至三眠早止桑60％,迟饷食24小时处理区的四至五龄食下量和消化量减少,五龄指数生长期缩短,体重减轻,处理结束龄和五龄中肠组织碱性磷酸酶、五龄肠液蛋白酶、五龄后部丝腺谷丙转氨酶活力降低、而一至三眠早止桑60％,一至二眠迟饷食12小时,对上述性状无明显作用,消化率和食物转化率不受止桑、偏食时间的影响。认为起蚕期长时间饥饿会损伤中肠机能,使蚕陷于营养不良,生长机能减弱,丝蛋白合成能力下降,表现出经济性状和抗病性的降低。     

家蚕饲养不同时间饷食技术研究与应用

针对养蚕眠起处理传统的“早止桑,迟饷食”技术,在开展早、中、迟饷食养蚕成绩比较,进而开展从起眠到饷食不同时间间隔饷食试验后,开展本试验,同时在农村开展了试验应用。结果,蚕儿发育整齐,全龄经过缩短,产茧量高茧质优良,缩短了养蚕经过时间,降低养蚕劳动力投入,提高工日产值。     

不同开食时间对扬州鹅早期生长发育的影响

本试验选用480只出壳时间集中在4 h内的0日龄扬州鹅雏鹅,随机分为A、B、C、D 4组,每组4个重复,每个重复30只,开食时间分别设置为出壳后12、24、36 h和48 h,研究不同开食时间对雏鹅生长发育的影响.结果表明,0～4周龄A组鹅体重显著高于D组(P＜0.05);从总体趋势看,A组和B组的饲料报酬高;D组消化器官和其他内脏器官(心脏、肝脏、胰腺)的重量均呈现出低于其余3组的趋势;免疫器官指数(脾脏指数和腔上囊指数)整体出现先上升到14日龄达到峰值后再下降的趋势.到28日龄时B组最大.因此建议雏鹅开食时间不宜晚于36h.     

大蚕期饥饿处理对蚕体生长发育及产茧和产卵性状的影响

分别在家蚕4龄眠起与5龄眠起时推迟饷食以及在5龄第3天进行饥饿处理,调查蚕体的生长发育、产茧和产卵情况,为制定新的家蚕共育模式技术规范以及一代杂交种生产的发蛾调节技术规范等提供试验依据。4龄起蚕推迟8 h饷食对幼虫5龄经过、全茧量、茧层量、茧层率、蛹体质量及蚕蛾羽化率、产卵量和良卵率均没有不利的影响;推迟16 h、24 h饷食,雌蚕的5龄经过延长及熟蚕体质量、全茧量、蛹体质量等性状成绩显著下降(P0.05),对雄蚕的影响较小(P0.05)。5龄起蚕分别推迟8 h、16 h、24 h饷食,5龄经过延长,熟蚕体质量、全茧量、茧层量、蛹体质量及产卵量、良卵数量等均显著下降(P0.01)。5龄第3天幼虫分别饥饿12 h、24 h,熟蚕体质量、全茧量、茧层量和蛹体质量均显著下降(P0.01);饥饿48 h后结茧率显著下降(P0.01),雌蚕和雄蚕分别仅为60.67%、42.66%。依据试验结果建议:农村养蚕如采用集中共育至4龄起蚕的模式,为方便共育蚕的分发配送,可适当推迟4龄起蚕的饷食时间,但推迟时间不应超过8 h;家蚕一代杂交种生产过程可将4龄起蚕饷食时间推迟8~16 h,调节对交品种发育进度;无论丝茧育还是种茧育,均不宜使旺盛生长期的5龄幼虫遭受饥饿,需预先调节好桑叶的充足供给。     

家蚕止桑饷食时间的研究——Ⅰ.家蚕止桑饷食时间与经济性状和病毒感受性的关系

试验结果表明,小蚕期蚕座中有40％的个体就眠时可停止飘叶,饷食应在基本起齐后12小时内进行。1—2眠迟饷食12小时对蚕的CPV感受性无影响,但延迟饷食或延续迟饷食的龄期,将提高蚕的CPV感受性。     

蜕皮激素添食时间与营茧速率之关系的研究

蜕皮激素在蚕桑生产中已广泛应用,但过去只着眼于节约桑叶和上簇齐一,对于减少不结茧蚕的发生未引起人们的重视。为此,在生产上如何应用蜕皮激素添食、减少不结茧蚕发生的研究,有一定的实际意义。我们结合生产上大规模添食蜕皮激素的同时,运用单因素随机区组试验设计,进行了蜕皮激素添食试验的研究,以期为生产服务。　　1　材料和方法　　11　供试品种和药剂　　蚕品种为春晓,蜕皮激素由海宁福安化工厂生产。　　12　试验设区　　收蚁至五龄第三天为普通桑叶育,五龄第三天后进行试验设计分区。设添食时间为因素(Ａ),有三个水平,即五龄饷食后…     

怎样养好晚秋蚕?

一、严格消毒防病。中、晚秋蚕期紧密相连,中间根本没有消毒时间。况且,此期病原量多、致病力强。因此,必须全面实行小蚕共育,才能解决上述矛盾。方法,先要对小蚕共育室及蚕具等彻底消毒,再是要做好蚕期中的消毒防病工作。一般在各龄饷食前和盛食前各撒1次防僵粉,     

稀土配合物应用于蚕种生产的研究春期蚕种生产中的应用效果

研究了稀土配合物在春期蚕种生产中的应用效果，采用喷匀桑叶，直接喂蚕的方法，提高了虫蛹生命率，单蛾造卵数，产卵数，良卵率等，通过小区饲养，提出了添食稀土配合物的时间为４龄２次，饷食后第２、３天各一次，浓度为０．０５％，５龄４次，起蚕饷食后第２天开始，每天１次，浓度为０．１％，在此基础上，进行大面积的对比饲养，添食区比ＣＫ区单位制种较大提高。经济效益显著。     

开食时间对雏鸡早期生长和内脏器官发育的影响

本试验旨在研究不同开食时间对雏鸡早期的生长性能及内脏器官发育的影响.试验选取1080只0日龄、体重相近的新扬州鸡雏鸡,根据开食时间不同,随机分成6个组,每个组3个重复,每个重复60只(30只公鸡,30只母鸡).出壳后一周内,每天从每个重复中随机挑选8只雏鸡(4公4母),分别称其活重后致死,取卵黄囊、肝脏、心脏、胰腺、法氏囊和小肠分别称重,测量小肠长度.结果表明,出壳后禁食36h对7日龄鸡体重没有显著负面影响,出壳后最长禁食时间不应超过60h.     

Night feeding for high-yielding dairy cows in hot weather: effects on intake, milk yield and energy expenditure

Heat load impairs the feed intake and milk yield of dairy cows: The higher their milk yield and energy expenditure (EE), the larger the expected effect. Our objective was to examine the efficacy of feeding such cows at night, which avoiding their access to feed for 5 1/2 h during the hot hours of the day, to reduce the heat load upon them in a hot climate. Approximately 120 cows in a herd in a hot region in Israel were allocated to two treatments: day (DFT) or night (NFT) feeding, which differed only in the schedule of feed allocation. The experiment was conducted from May to September 2000 (118 days). The cows were group fed on a total mixed ration, and the daily amounts of feed offered and of orts collected were recorded. The daily group average milk yield was also recorded. Ten cows in each group were selected for individual measurements. The energy expenditure of these cows was estimated once before and three times during the experiment, by monitoring heart rates and measuring oxygen consumption. The rectal temperatures and respiration rates (RR) of these cows were measured in the morning and afternoon on two consecutive days in August. Cows on NFT had lower feed intake but similar milk yield to that of DFT cows, and NFT cows had better milk yield persistence over time. The effects of the temperature-humidity index (THI) on milk yield and intake were similar in the two treatments. The rectal temperature and respiration rate, and the increase in these measures from morning to afternoon hours, did not differ from DFT and NFT cows. The energy expenditure of NFT cows was lower than that of DFT cows, and their efficiency of energy utilization for milk production was higher.     

Feeding time can alleviate negative effects of heat stress on performance,meat quality and health status of turkey

1. A total of 180 one-day-old turkeys were randomly assigned to 6 equal groups to investigate the effect of feeding time on growth performance, carcass characteristics, meat quality, leg problems and physiological responses of growing turkeys under the high temperature conditions of summer.

2. Birds of the first group were ad libitum fed and were considered as the controls (C). The second group (T1) was given 80% of diet in the morning and 20% of diet in the afternoon, the third group (T2) was given 60% of diet in the morning and 40% of diet in the afternoon, the fourth group (T3) was given 40% of diet in the morning and 60% of diet in the afternoon, the fifth group (T4) was given 20% of diet in the morning and 80% of diet in the afternoon and the sixth group (T5) was given 100% of diet in the afternoon.

3. Body weight, body weight gain and feed conversion ratio were improved with T2, T3, T4 and T5 in comparison to control or T1 under heat stress conditions. No significant impacts on carcass traits and meat quality due to changing the time of feeding were seen, except for tenderness and juiciness.

4. Feeding in the afternoon (100%) decreased body temperature and tonic immobility test score, which were positively related with the health condition of the birds.

5. The incidence of leg problems, plumage condition and breast blisters were not significantly different among the experimental groups.

6. It is concluded that feeding turkeys mainly or totally in the afternoon (T4 and T5, birds were fed with 80% or 100% of the diet in the afternoon) can be used as a strategy and a managerial tool for improving growth rate, feed utilisation, carcass and meat quality, as well as health status of growing turkeys reared under hot climate conditions.     

Feeding and drinking behavior of mares and foals with free access to pasture and water

The feeding and drinking behavior of 11 mares and 15 foals living on pasture with free access to water was recorded during 2,340 15-min focal samples taken over 2 yr. Lactating mares on pasture spent about 70% of the day feeding. Foals began feeding on their first day of life. As they grew older, they spent progressively more time feeding, but still spent only 47 +/- 6% of the time feeding by 21 wk of age. Foals fed primarily during the early morning and evening. While grass formed the major proportion of the diet of both foals and mares, they also ate clay, humus, feces, bark, leaves and twigs. Almost all feeding by foals was done while their mothers were feeding. Movement to water sources was frequently, but not invariably, carried out by an entire herd. Frequency (P = .005) but not duration (P greater than .05) of drinking bouts by mares increased as the temperature increased. Frequency was greatest at 30 to 35 C, at which temperature mares drank once every 1.8 h. Frequency of drinking varied with the time of day (P less than .01), being rarest during the early morning (0500 to 0900 h eastern daylight time) and most frequent during the afternoon (1300 to 1700 h). Drinking by foals was very rare. The youngest age at which a foal was observed to drink was 3 wk, and 8 of 15 foals were never observed to drink before weaning.     

灰雁繁殖期的行为日节律及时间分配

2011年4～6月,采用瞬时扫描法对徐州睢宁金桥禽业发展有限公司2对繁殖良好的灰雁的繁殖行为时间分配和活动节律进行研究,采用非参数检验的Kruskal-Wallis H法分析不同性别灰雁繁殖前中后期行为的性别差异,以及相同性别的灰雁在繁殖的不同时期的行为差异。结果显示：灰雁在采食、理羽、静立、趴卧、孵化等行为上存在着明显的节律性。取食行为多发生在上午和下午的中间时段,孵化多在早晨和傍晚,而中午的大部分时间处于休息状态。孵化期内雌雄个体的行为差异很大,灰雁繁殖时期各种行为所占的比例不仅存在着一定的性别差异,而且同一性别个体在不同的繁殖阶段各种行为所占的比例也有很大变化。     

Effect of setting a maximum milking time,from peak lactation,on production,milking time and udder health

Abstract

AIM: To examine the effect of setting a maximum milking time, from peak lactation until drying-off, on production, duration of milking, and udder health of dairy cows.

METHODS: Forty cows were assigned in twin-pairs to be either milked until cups were removed at a milk flow-rate threshold of 0.35 kg/minute (Control), or until cups were removed at a milk flow-rate threshold of 0.35 kg/minute, or maximum time, whichever came first (MaxT). The maximum time was set by determining the milking time of the 70th percentile cow when ranked from fastest to slowest, irrespective of yield. The milking routine was typical of that practised on dairy farms in New Zealand, and involved no pre-milking preparation. The study began at peak lactation (68 (SD 7) days in milk; DIM) and continued for 26 weeks. Duration of milking and milk yield were measured for each milking. Composition of milk was determined from weekly herd tests, and milk quality from fortnightly somatic cell counts (SCC). Completeness of milking and teat condition were assessed during the study. The bacterial status of quarter milk samples was determined at the beginning and end of the study, and all treated cases of clinical mastitis recorded. ANOVA was used to examine the effect of treatment group on variables of interest.

RESULTS: Total milk, fat and protein yields during the study period did not differ between treatments. On average, 30.3% of the morning and 27.6% of the afternoon milkings of MaxT cows reached the maximum time at which cups were removed, and were therefore shortened. While the average milking time of the slowest-milking cow was longer for the Control compared with MaxT group in Weeks 1–18, the average milking time did not differ between treatments. There was no difference in overall SCC, and the incidence of clinical mastitis, or the percentage of infected quarters at drying-off, was similar for the MaxT and Control cows.

CONCLUSION: The results show that setting a maximum milking time can reduce the milking time of slower-milking cows in a herd without compromising overall herd production and udder health.

CLINICAL RELEVANCE: Although the numbers of cows in the study were small there was no evidence of a major increase in SCC, or subclinical or clinical mastitis when a maximum milking time was set for slower-milking cows.     

The Diurnal Variation of Urea in Cow’s Milk and how Milk Fat Content,Storage and Preservation Affects Analysis by a Flow Injection Technique

Six Swedish Red and White dairy cows, producing 20-39 kg of 4% fat-corrected milk were given a ration balanced in energy and protein. They had access to feed from 05.15 to 09.00 and from 13.00 to 16.30 and were milked at 06.15 and 15.30. The milk was analysed for urea with a FIA technique.There was a significant diurnal variation in milk urea. The highest values were found 3–5 h after the beginning of the morning feeding and the lowest values (down to 60% of the max. values) during late night. Within 1 h after the start of the morning feeding the urea values had increased significantly, but they had decreased within the same time after the start of the afternoon feeding. Since there was a pronounced diurnal variation in the milk fat content, the urea concentration was also recalculated to concentration in the water phase of the milk. It was higher in that phase, but the pattern of the diurnal variation was not changed significantly. However, analyses on milk with a very high fat content may give misleading results.There were no important differences in the milk urea concentration of different udder quarters. When calculated as concentration in the water phase of the milk, no differences in urea concentration were found between the beginning and the end of milking. The analytical method had a good precision (coefficient of variation max. 3%). The milk urea concentration was not changed significantly after storage during 10 days at 4°C when no preservative was added; but after 17 days the milk had turned sour and the urea value had increased. When a preservative (bronopole) was added the urea concentration remained unchanged during 17 days. Deepfreezing did not influence the urea concentration.     

Sexual disparity in activity patterns and time budgets of angulate tortoises (Chersina angulata) on Dassen Island,South Africa

Behavioural frequencies and time budgets for male and female Chersina angulata were recorded in spring, September 2004. The daily activity of the population was 10.51 ± 0.42 h (mean ± CI), but individual males and females were in the open for 2.57 ± 1.12 h and 1.58 ± 1.44 h, respectively. Both sexes spent nearly 3.5 h per day basking with 90% of the basking time in the cover of sparse vegetation. Feeding and walking were the most frequent active behaviours. The activity pattern of the sexes differed between 10:00 and 12:00 in the morning when males spent more time out of cover on active behaviours, particularly feeding, than females did. The daily activity pattern of the population peaked between 10:00 and 12:00, reflecting the activity pattern of the more active sex, males. Females were out of cover, active, and feeding at higher temperatures than were males. The high temperatures probably allowed females to complete activities more efficiently, reducing their exposure time and predation risk. Although fighting and mating represented small fractions of male time budgets, the extended physical presence through walking and feeding may help males to establish dominance hierarchies and enhance mating success.     

Sucking behaviour of hand-reared newborn dairy calves

AIM: To determine the feeding ability of calves during the first 4 days after birth. METHODS: The sucking behaviour of 171 dairy calves, fed from individual bottles during the first 4 days after birth, was evaluated by quantifying the volume of colostrum consumed, the duration of feeding, and speed of drinking. Calves had been separated from their mothers and brought into a rearing shed in the morning, when < 24 h of age, and were offered 2 L colostrum from a bottle in the afternoon of the same day, and twice daily thereafter. RESULTS: Newborn calves became efficient suckers from bottles within 24 h of removal from their dams (collection). On the day after birth, 95% of calves drank the 2 L of colostrum offered during the afternoon feed, and by Day 4 virtually all calves (99%) drank this amount. Calves that had inadequate colostrum from their dam were more likely to drink all 2 L offered after collection, but a small number of calves that had not had colostrum from their dams and drank < 500 ml at the afternoon feed following collection were likely not to drink 2 L on the following days. However, calves that did not drink all 2 L on Day 1 were not disadvantaged in comparison to those that did, in that they were equally likely to drink 2 L on Day 4. CONCLUSIONS: The majority of calves became efficient drinkers within 48 hours of birth, but a small number of slow feeders may need individual feeding at least up to 4 days after birth.     

Diurnal variation of ghrelin, leptin, and adiponectin in Standardbred mares

Twelve Standardbred mares underwent blood sampling for 24 h to test the hypothesis that there is diurnal variation of humoral mediators of peripheral energy balance including active ghrelin, adiponectin, leptin, glucose, insulin, and cortisol. The experiment was conducted under acclimated conditions. Grass hay and pelleted grain were provided at 0730 and 1530. Plasma concentrations of active ghrelin and leptin concentrations both peaked (47.3 +/- 6.5 pg/ mL and 5.9 +/- 1.1 ng/mL, respectively; P < 0.05) at 1550, 20 min after feeding. Active ghrelin decreased (P < 0.05) to 28.9 +/- 4.5 pg/mL overnight. The nadir of leptin (4.6 +/- 0.9 ng/mL) occurred at 0650. Neither hormone showed variation (P > 0.05) after the morning feeding. Plasma glucose and insulin concentrations increased (P < 0.05) in response to feeding; however, the morning responses (glucose = 96.9 +/- 2.6 mg/dL; insulin = 40.6 +/- 7.3 uIU/mL) were greater (P < 0.05) than the afternoon responses (glucose = 89.9 +/- 1.8 mg/dL; insulin = 23.2 +/- 4.3 uIU/mL at 180 and 60 min after feeding, respectively). Cortisol concentrations increased (P < 0.05) during the morning hours, but did not respond to feeding, whereas adiponectin concentrations remained stable throughout the study. Hence, active ghrelin and leptin may be entrained to meal feeding in horses, whereas adiponectin seems unaffected. We concluded that there seems to be a diurnal variation in glucose and insulin response to a meal in horses. Furthermore, elevated glucose and insulin concentrations resulting from the morning feeding may be responsible for the increase in leptin concentration in the afternoon.