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1.
In this article, we aimed to describe the changes related to mating season in red deer, especially those related to antler growth, body condition score, testosterone and cortisol. Antler growth was studied in 17 Iberian red deer males, including body weight, antler length, biometric measures and testosterone and cortisol determination during 15 months. Body weight, body condition score, thoracic perimeter (TP), neck perimeter (NL) and testicular diameter (TD) showed the highest values immediately before mating season (autumn), decreased during it and remained constant at winter. Antler growth lasted 158 days and produced antlers with a final length of 80.8 ± 2.0 cm. Testosterone and cortisol showed seasonal changes with maximum values at September and May, respectively. Final antler size was related positively to cranial longitude, TP, NL, TD and body weight at casting time. No relationship between weight loss during precedent mating season and current antler size was found, but spring recovery weight was positively related to final antler size. Final length was related to the descent in testosterone values during previous mating season and to body weight before it. Spring recovery weight was related to relative weight loss during previous mating season. These results suggest that there is no relationship between the reproductive effort performed during one season and the next year size of the antler. In contrast, antler size was positively related to spring recovery weight, in the sense that those deer that recover a higher percentage of body weight at the early stages of antler growth develop higher antlers.  相似文献   

2.
Various methods can be used to feed dairy calves that may influence calf performance and these include changing frequency of feeding or age at weaning. Two trials were conducted to determine effects of feeding frequency and weaning age on calf growth, health and rumen development, where 124 Holstein heifer and bull calves were weaned at 3, 4, 5 or 6 weeks of age. During Trial 1, milk replacer (12.5% DM; 22% CP, 15.6% fat) was fed at 10% BW twice per day until 1 week prior to weaning when intake was reduced to 5% BW. During Trial 2 calves were fed at 10% BW in two feedings until 14 days, then at 10% BW once daily until 1 week prior to weaning when milk replacer was reduced to 5% BW. Blood glucose and urea nitrogen, BW 4 h post-feeding, heart girth, hip height, and withers height 4 h post-feeding were obtained weekly. Growth and structural measurements were similar for all treatments up to 8 weeks of age in both trials. Blood constituents and health observations were not different between trials. Similar growth and performance between treatments in both trials through 8 weeks of age indicate that calf performance is not affected by weaning early and feeding once daily.  相似文献   

3.
为达到更好的锯茸止血效果,对梅花鹿锯茸时出血特点及锯茸止血药物应用效果进行了观察:收取初角茸时呈渗出状出血;收取二杠茸时呈线状出血;收取三杈茸和畸型茸时呈喷射状出血,并且有节律地进行搏动。出血量随着鹿茸的产量和茸根围度的增加而增多,但是当收取茸根围度为(20.3±0.6)cm的畸型茸时却不存在这种明显的相关关系。同一茸型不同年龄的鹿,因茸重、茸根围度的不同出血亦有差别。根据鹿茸的组织结构、生长规律和梅花鹿生理特点,选用由中药组成的外用锯茸止血药方剂,通过锯茸止血试验,结果表明,该锯茸止血药无刺激性,止血快,抗感染能力强,创面愈合良好,对再生茸产量没有明显影响(P>0.05)。  相似文献   

4.
天山马鹿数量性状相关的统计分析   总被引：1，自引：0，他引：1  
探讨了凉泉天山马鹿上锯公鹿的体重、茸重、茸的鲜干比例性状与鹿年龄、茸重性状与体重 ,体重、体尺和茸尺性状与茸重的关系。结果表明 :在一定年龄段 ,这些数量性状除了体尺中角基距性状与茸重呈强负相关 (-r,P <0 0 1 )外 ,多呈极显著正相关 (P <0 0 1 ) ,少数呈显著正相关 (P <0 0 5 ) ,并建立了线性回归方程 ,为预测并比较天山马鹿各锯时的体重、茸重、体尺、茸尺和茸的鲜干比例水平及制审定其检测标准提供了科学依据。  相似文献   

5.
鹿茸是雄性鹿的第二性征,也是哺乳动物器官中唯一能完全再生的。鹿茸是从着生于头部的被称为角柄的永久性骨桩上发生、再生和脱落的。鹿接近青春期时,雄激素逐渐升高并刺激角柄生长。如果在角柄发生前将公鹿去势,角柄将终生不能发生,但当给其施以足够的外源睾酮激素时,可以诱导它们重新生长。研究结果发现,角柄的发生除了与雄性激素有关外,还受到营养水平的调节,只有当鹿的体重达到一定阈值时,角柄才能发生。进一步研究结果发现,营养水平通过调控体内胰岛素样生长因子1(kinsulin-like growth factor l,IGF1)而调节角柄的发生。因此角柄发生不仅与雄性激素有关,也依赖于体内IGF1水平。由于鹿茸的完全再生取决于角柄,因此,对角柄发生机制的研究是对鹿茸再生研究的一个重要方面。作者针对IGF1和睾酮激素对鹿角柄发生所产生的影响进行综述,为研究角柄发生机制提供重要依据。  相似文献   

6.
鹿茸角是哺乳动物唯一的失去后还能完全再生的器官,人们对鹿茸角再生的分子机理了解甚少。本试验以梅花鹿为研究对象,通过原位杂交方法对Bcl-2在梅花鹿茸角中的表达进行了研究。结果显示,Bcl-2在梅花鹿茸角表皮层内表达甚微,在茸角真皮层、间充质层及软骨层等处均有表达,但在表达强度上存在一定差异。在真皮层中,Bcl-2在真皮成纤维细胞中有较强的表达,在鹿茸间充质细胞中也有少量Bcl-2的表达;在鹿茸软骨层中,Bcl-2在软骨细胞中的表达量很高,主要表达在增殖区的软骨细胞中。这表明Bcl-2可能在梅花鹿茸角再生过程中起重要的调节作用。  相似文献   

7.
Two feeding trials (early and late lactation) were conducted to measure ad libitum forage intake by beef cows from three breed groups of similar mature weight, but with different milk production potential. Twenty-four cow-calf units, eight from each milk production level (low, medium and high) were grouped (two/pen) based on similarity of cow weight and previous weigh-suckle-weigh and calf weaning weight data. Each pair of cow-calf units was confined to separate pens and allowed ad libitum access to chopped native Sandhills meadow hay. Dry matter intake, cow and calf BW and calf milk consumption were determined. Daily DMI (kg/hd) and milk consumption showed a positive linear response (P less than .05) among low, medium and high milk-producing cows. When cow DMI was expressed as g/unit mean cow BW during the trial, both a positive linear (P less than .05) and a quadratic response (P less than .01) expressed the relationship among production levels during early and late lactation. Calf forage intake, birth weight and adjusted 181- and 205-d weaning weight had no linear or quadratic relationship (P greater than .10) to milk production levels. However, June 1 calf weight, actual calf weaning weight and calf rate of gain (birth to weaning) had a positive linear (P less than .07) relationship. Best fit regression models with DMI as the dependent variable were developed for each trial based on R2 and CV values of the potential models. The best fit model (R2 = .94, SE = .33) for early lactation included production level as a class variable with cow BW.75 and calf birth weight as independent variables. The best fit model (R2 = .92, SE = .53) for late lactation included actual weaning weight in addition to the variables used during early lactation.  相似文献   

8.
This study examines milk production and the effect of milk production and sex of calf on body weights and gains of red deer calves and hinds of the Iberian subspecies (Cervus elaphus hispanicus). Milk production was assessed in 14 hinds by weighing calves before and after suckling and by adjusting these values to the Gamma function. Gamma estimates of total milk production up to d 105 were similar to the amounts computed directly from double weighing. Hinds showed two types of lactation curve: 1) the standard mammal lactation curve, with an asymmetrical peak at wk 2 to 4 (Type I) and 2) decreasing curves with no peak (Type II). Although there was great interindividual variability, hinds with Type I curves showed a trend to produce more milk than those with Type II. The type of curve did not seem to affect weight variables of the calf or those of the dam. Calves that gained more weight consumed greater amounts of milk (P<.05). Males were heavier than females at birth (P<.05), but males did not differ from females in their weight at 105 d, milk consumption, and gain. Gender did not affect hind weight, but dams of male calves showed a trend to be lighter (P = .063) at d 105 than dams of female calves. Our results suggest that suckling differences found in other studies between male and female calves may not involve differences in milk production, although other rearing costs seem to affect hind weight losses. They also suggest that the curve type may not depend only, as reported, on the nutrition plane.  相似文献   

9.
以梅花鹿为研究对象,通过原位杂交方法对细胞周期蛋白D1（cyclin D1）在梅花鹿茸角中的表达进行了研究。结果显示,cyclin D1在梅花鹿茸角表皮层内表达极少,在茸角真皮层、间充质层及软骨层等处均有表达,但在表达强度上存在差异。在真皮层中,cyclin D1在真皮成纤维细胞中有较强的表达,在鹿茸间充质细胞中也有少量cyclin D1的表达,在鹿茸软骨层中,cyclin D1在软骨细胞中的表达量非常高,主要表达在增殖区的软骨细胞中。结果表明,cyclin D1可能在梅花鹿茸角再生过程中起重要的调控作用。  相似文献   

10.
Hummels are antlerless red deer stags. This abnormality has been attributed to poor feeding conditions which result in failure by the deer to grow complete pedicles. Incomplete pedicles lack the potential to develop normal antlers. The histological examinations in this study showed that the rudimentary pedicles (5 mm and 15 mm in height) grown by the two hummels respectively were developed by intramembranous ossification. This is the way that the frontal lateral crests of normal deer are formed, while, in contrast, antlers grow by endochondral ossification. The transition between the ossification types is most important, and occurs during pedicle growth. Therefore, we suggest that the antlerless condition of hummels is due to their failure to initiate true pedicle growth (which has the potential to develop into an antler) because the change from one ossification type to another does not occur. In view of the fact that both hummels were very small in terms of weight (33.7 kg and 51.8 kg, respectively) for their age, it is possible that nutritional cues are necessary for complete pedicle formation. Presumably these cues act synergistically with androgens for the development of the pedicle/antler as a secondary sexual character. It is possible that nutrition controls pedicle initiation through the IGF1 pathway.  相似文献   

11.
特效生茸宝系由多种中西药物组成的复方药物添加剂，具有明显的促进鹿茸生长的效果。为了进一步研究其促鹿茸生长机理及对鹿茸品质的影响，按日量３０ｇ／头，添加于精料中，连喂７０ｄ。采集锯茸时茸基部流出的血液和锯下的鹿茸，分别测定了某些血液生理生化指标和鹿茸氨基酸含量。结果，饲喂特效生茸宝的鹿，血液红细胞数、Ｈｂ、血清总蛋白量均增加（Ｐ〈０．０５），ＡＫＰ活性增高（Ｐ〈０．０１），鹿茸中氨基酸含量增高。由此  相似文献   

12.
鹿茸是雄性鹿科动物(除驯鹿外)特有的能够周期性再生的器官,其生长发育受到多种因素的共同调控。miRNA(microRNA)是一类在真核生物中发现的内源性的具有调控功能的非编码RNA,在基因表达调控、细胞周期、生物体发育等方面发挥着重要的调控作用。本文从miRNA的相关技术、鹿茸组织中miRNA的鉴定、miRNA对生长因子的调控作用、miRNA对鹿茸细胞增殖的作用以及miRNA对鹿茸再生调控的研究几个方面就现有miRNA对鹿茸生长发育的研究进行总结和展望,为今后鹿茸生长发育机理的诠释具有一定的意义。  相似文献   

13.
梅花鹿茸鲜重与年龄的相关性研究及经济效益分析   总被引：1，自引：0，他引：1  
以江苏地区的梅花鹿为对象,研究分析了梅花鹿鹿茸重量与其年龄之间的相关性。结果表明:9龄内梅花鹿的鹿茸重与年龄呈正相关(r=0.767,P<0.05),它们之间线性回归方程为y=0.345x+1.186。梅花鹿3～8锯的鲜茸单产很高,平均水平达3.28kg/锯。公鹿鲜茸重的变异系数在2～6龄之间逐渐减小,7龄之后又有上升的超势,其中以5～7龄的变异系数最小,分别为16.2%、6.1%、11.7%。相关数据分析表明,梅花鹿公鹿在1～4龄内经济效益较差,从5龄开始获利,年获利逐年增加,这种趋势与梅花鹿的茸产量变化趋势是一致的。  相似文献   

14.
半乳糖凝集素1蛋白及其生物学功能   总被引：1，自引：0，他引：1  
半乳糖凝集素1(Galectin-1)是一种分子质量约为14 ku的β-糖结合蛋白,是动物凝集素家族的成员之一。作为多种癌症的诊断指标,治疗癌症的新突破口,对Galectin-1的研究备受关注。此外,Galectin-1分布广泛,与多种正常生物功能相关,如细胞生长、神经修复、血管再生、软骨形成等。现阶段,关于Galectin-1在鹿茸再生中的研究很少,但鹿茸再生中许多过程与Galectin-1的功能高度相关。与肿瘤同样高速生长且高表达Galectin-1的鹿茸组织并不发生癌变,这可能对癌症的研究有所启发。为了寻找治疗癌症的新方法,解释鹿茸再生机制,了解Galectin-1蛋白在肿瘤和鹿茸中的功能研究进展至关重要,文章就其进行了综述。  相似文献   

15.
西丰梅花鹿品种选育研究和推广效果   总被引：4，自引：2，他引：2  
采用个体表型选择种鹿、单公群母配种和大群闭锁繁育的方法,并应用对幼鹿的科学培育和选育鹿科学饲养管理等综合配套技术,经过193 1～1973年7个世代家养舍饲繁育、1974年选定系祖鹿建立选育群和育种核心群至1995年3个世代的连续系统选育,由源于东北梅花鹿和地方品种的西丰梅花鹿品种,在西丰县育才等4个参茸场育成了半山区舍饲型的3 60 1只西丰梅花鹿品种,其中,核心群鹿92 9只,占2 5 8%。该品种具有体貌相对一致,体型中等,体质结实,鲜茸平均单产3 2 0 5kg,成品茸平均单产1 2 5 9kg,茸的支头大,嘴头肥大,优质率高( 70. 9% ) ,畸型茸率低( 7.6% ) ,繁殖成活率77 .8% ,生产利用年限10年,遗传性状稳定,茸重的遗传力为0.49,重复力0. 63 ,产仔日期重复力0 .68,种用年限2.2年,鲜茸重的遗传进展5 19g,年改进量89g ,F1的杂种优势率茸重性状13.0 4% ,繁殖成活率的为18.94% ,选育的第Ⅲ世代年只均新增纯收益成年公鹿10 3 0元,成年母鹿790元,已获经济效益12 2 1万元,科研投资年均纯收益率5 .63元/元;又经1996～2 0 0 4年在本县和2 0多个省、市、自治区上百家万余只的推广应用表明,西丰梅花鹿的生产性能和遗传性能稳定,稳产高产高效,年只均创净效益成年公鹿15 0 0元,成年母鹿160 0元,其杂交改良效果,尤其是与双阳  相似文献   

16.
Changes in day length and the related secretion of melatonin and prolactin are of particular significance in sheep, as they determine reproductive processes, the last stage of which is lactation. The aim of the present study was to examine the dependence of the lactation duration and efficiency on the season of lambing (January—Group I/June—Group II) in relation to the hormonal status of milking ewes (Polish Longwool). The possibility of artificial extension of the milking period in late-lambing ewes by application of prolonged day length, 16 h of light–8 h of darkness (16L:8D), was introduced additionally (Group III). Measurements of plasma levels of prolactin and melatonin were used as parameters of season-dependent hormonal regulation of milk production in this seasonally breeding species. Although during the first 28 days of lactation sheep of all groups produced similar amounts of milk (based on the weight gains of the lambs), our results clearly showed that during the period of machine milking (from weaning at 56 day to the dry period) the level of milk production in Group I was almost twice that noted in Group II. Thus, the highest milk yield was obtained from sheep during the period when the days became longer, i.e. from March to May, which was accompanied by an increase in prolactin secretion. In both groups, melatonin secretion was found to increase while milk performance parameters and prolactin secretion decreased during the shortening photoperiod. The sustained decreases in milk production and prolactin secretion were also observed during the autumn months in sheep from Group III, despite the low level of melatonin. The present study showed that time of lambing and related photoperiod length could significantly affect the milk production of sheep that have a clear season of sexual activity. Maintenance of June-lambing sheep under the 16L:8D regime failed to extend the high prolactin level and lactation considerably into the autumn months. The spontaneous decrease in prolactin secretion observed under the long artificial photoperiod indicated for a development of refractoriness, which could also limit the lactation period.  相似文献   

17.
The low nutrient intake shortly after weaning is a major cause of post-weaning problems. Feed intake after weaning is strongly related to feed intake during lactation. Feed intake during lactation, however, varies considerably between litters. We hypothesised that prenatal and postnatal exposure to certain flavours would increase the intake of feed containing the same flavours pre- and postweaning. Multiparous sows did (n = 17) or did not (n = 14) receive 50 g garlic granulate/powder and 25 g aniseed as daily additive to their diet during the last month of gestation and during lactation. From day 14 of lactation, litters were submitted to intermittent suckling: 12 h separation form the sow each day. During lactation, all litters had 40 g garlic and 20 g aniseed per kg added to their creep feed. After weaning, half of the litters had no additive in their diet. Piglets were weaned at 4 weeks (13 litters) or at 6 weeks (18 litters). At 6 weeks of lactation, litters of which the dam received the flavour in her diet, had a higher feed intake (309 ± 43 vs 233 ± 35 g/p/d) than litters of dams without the flavour, although the difference was not significant. Sow diet had no effect on postweaning feed intake, but postweaning piglet diet did. Late (week 6) weaned litters receiving the flavoured feed had a higher feed intake from 3 to 10 days after weaning (833 ± 38 vs 687 ± 58 g/p/d). Weight gain during the first 10 days after weaning was not affected by sow or pig diets. Feed intake and weight gain shortly after weaning were strongly related to feed intake during lactation (overall R = 0.64, P < 0.05 and R = 0.77, P < 0.05). We conclude that early experience with flavours increases later acceptance and improves adaptation to post weaning conditions.  相似文献   

18.
Angus bulls (n = 16) selected for either high- or low-milk EPD but similar growth EPD were mated within location at random to Angus cows. Daughters were bred to calve at 2 yr of age and annually until 6 yr of age. Milk yield was measured four times during lactation with a portable milking machine to estimate 12-h milk yield. Milk was collected for analysis of the percentage of fat and protein. A mixed model procedure was used to analyze the weaning weight, milk yield, and milk component data. The model for weaning weight included location, genetic line of sire, gender of calf, and age of dam. Calf age at weaning was used as a covariate. The model for the milk yield and components included location, genetic line of sire, gender of calf, period, and age of dam. Random effects for all models included sire of dam nested within line, sire of calf, and year. Genetic line was a significant source of variation for milk yield (P < 0.01) and weaning weight (P < 0.01) but not for percentage of fat or protein. Location was significant for milk yield (P < 0.01), fat (P < 0.01), protein (P < 0.01), and weaning weight (P < 0.01). The interaction of line with location was not significant except for percentage of protein (P < 0.01). Age of dam was significant for milk yield (P < 0.01), weaning weight (P < 0.01), and percentage of protein (P < 0.01), but not for percentage of fat (P = 0.29). Line difference for mean weaning weight was 18.1 kg, which is similar to the difference between lines for milk EPD (19 kg). Weaning weights from high-milk EPD line daughters were heavier (P < 0.01) than low-milk EPD line daughters at each age of dam evaluated. Cows nursed by males had higher milk yields (4.33 kg/12 h) than cows nursed by heifers (4.0 kg/12 h). The difference in yields for gender was significant for 2-, 3-, and 5-yr-old cows, but not for 4- (P < 0.052) and 6-yr old (P < 0.15) cows. Correlation coefficients between weaning weight and weaning EPD, milk EPD, and total maternal EPD were greater than zero (P < 0.01) (0.76, 0.65, and 0.89, respectively). Daughters of sires with high-milk EPD produced more milk at each age and weaned heavier calves than daughters of sires with low-milk EPD. These results confirm the value of milk EPD for improvement of weaning weights in beef cattle and also validate age of dam effects on milk yield and the associated effects on weaning weights.  相似文献   

19.
The efficacy of controlled-release melatonin implants to advance the onset of the breeding season was assessed in 1-year-old red deer hinds on five commercial deer farms in various localities in the North Island of New Zealand. Between 44 and 60 hinds in each of six herds were equally divided among treatment and control groups at each site. Melatonin treatment commenced between 27 November and 16 December and was achieved by the subcutaneous administration of two 18 mg melatonin implants. Three doses were given at about 30 day intervals. Two adult stags for each hind group were treated with three 18 mg melatonin implants concurrently on either two or three occasions. On each property, treated and control hinds were joined as one herd to treated stags commencing 30 January-10 February and concluding 15 May-2 June. The hinds in the four experimental herds underwent rectal ultrasound examination May-June to estimate conception rate and foetal age. Calving dates, hind and calf mortalities, weaning weights, and the antler growth cycle and harvesting data were recorded. Overall, treatment with melatonin resulted in an average advance of the median calving date of 22 days (range 12-36 days) when compared with untreated controls in the same herds. Pregnancy rates were 91.3-100% in treated hinds and 63.6-100% in untreated hinds. There were no differences in calf mortality or calf sex ratio between treated and untreated groups. No hind deaths could be attributed to melatonin treatment. The weaning weights of calves were 5.68 kg and 4.43 kg heavier for the male and female offspring of treated hinds respectively, compared with those of control hinds. Treated stags commenced rutting behaviour earlier than normal and the antler casting and growth cycle was advanced. Treatment resulted in advancement of the seasonal pattern of coat changes in hinds and stags, but no untoward side effects of the melatonin treatments were observed.  相似文献   

20.
Angus bulls (n = 24) were selected for either high or low milk EPD, but with similar growth EPD and mated within location (n = 6) at random to Angus cows. Daughters from these matings were bred to calve first at 2 yr of age to common reference sires across locations. Lactation records for 192 daughters were used to evaluate 12-h milk yield, percentage of milk fat and protein, and weaning weight of offspring. Milk production was measured four times during the lactation at regular intervals within location. Dams were separated from their calves the night before milking and milked with a portable milking machine the next morning to estimate 12-h milk yield. A sample of the milk was collected from each cow and analyzed for percentages of milk fat and protein. Data were analyzed as repeated records of the dam. Fixed effects were location, genetic line of sire, gender of calf within location, and milking period, with postpartum interval used as a covariate. Fixed effects and the random effects of sire of dam nested within line, sire of calf, and year were estimated by REML. Genetic line was an important source of variation for milk yield (P < 0.01) and percentage of milk fat (P = 0.03) but not for percentage of milk protein (P = 0.49). Location was significant for all three milk variables (P < 0.01), but the interactions between line and location were not significant. Gender of calf was significant for milk yield (P = 0.04) but not for percentage of milk fat or protein. Line (P = 0.02), location (P = 0.01), calf gender (P = 0.01), and age at weaning (P = 0.01) were significant sources of variation for weaning weight but the interaction of line and location was not (P = 0.69). The correlation coefficient between the sire's milk EPD and 12-h milk yield was significantly different from zero (r = 0.56). The difference between the least squares means for high and low lines for milk yield was 0.66 kg/12 h and the difference was 15.3 kg for weaning weight. The results indicate that there was not evidence for a genotype by environment interaction in milk production for daughters from divergent sires selected for high or low milk EPD.  相似文献   

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