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1.
1. Growth of the oesophagus, proventriculus, gizzard, intestine, liver and pancreas weight was investigated in Mallards, White Pekins, Muscovies and a Muscovy x White Pekin cross. The birds varied in age between hatching and 154 d. The data were analysed by fitting both the Janoschek growth curve and the allometric formula. 2. The growth rate of all organs, except the oesophagus, peaked earlier (30 d for Muscovies and 14 d for the other breeds) than body weight and they grew faster to any given percentage of their final weight. In contrast, oesophagus weight showed growth curve characteristics similar to body weight. 3. Oesophagus weight showed simple, slightly negative allometry. The remaining organs followed complex allometry that can approximately be described by 2 allometric stages. The 1st phase was isometric to positive allometric. The 2nd showed marked negative allometry. 4. These growth patterns are assumed to be generally present in birds.  相似文献   

2.
Nutritional conditions during the intrauterine stage are an important developmental programming factor that can affect the growth and metabolic status during foetal development and permanently alter the phenotypes of newborn offspring and adults. This study was performed to examine the effects of intrauterine catch‐up growth (IUCG) on food intake, post‐natal body growth and the metabolic status of offspring and growing rats. Control pregnant rats were fed ad libitum during the entire gestation period. For the IUCG regimen, pregnant rats were fed 50% of the food of the controls from pregnancy days 4 through 11 (8 days), followed by ad libitum feeding from pregnancy days 12 through parturition. The birth weight of offspring was not affected by the IUCG regimen. At weaning, offspring from each treatment group were assigned to two groups and given either a normal diet or high‐fat diet (HFD) for 12 weeks until 103 days of age. In the normal diet group, the IUCG offspring showed a 9.0% increase (< 0.05) in total food intake, were 11.2% heavier (p < 0.05) at 103 days of age and had an 11.0% greater (p < 0.05) daily weight gain compared with control offspring. The IUCG regimen did not affect body glucose and lipid metabolism. After exposure to the HFD, the IUCG regimen has not exacerbated metabolic disorders. In conclusion, our findings suggest that the IUCG nutritional regimen during pregnancy can increase the food intake and post‐natal body growth of offspring without inducing metabolic disorders such as obesity and insulin resistance. The IUCG nutritional regimen might be used to improve the food intake and post‐natal body growth of domestic animals.  相似文献   

3.
肉用仔兔消化系统发育与机能特点变化的研究   总被引:4,自引:1,他引:3  
经34只初生至12周龄的新西兰肉兔试验,初生兔中部消化器官发育最快,主要是肝的重量占中部器官的66%或占消化器官的42%。在前部器官中胃的发育最快,舌相对也比较大,舌的重量占前部器官的31%或占消化器官的8%,4周龄后舌的重量稳定在占消化器官4%的水平上。初生兔后部消化器官发育较晚,初期作用不大。3周龄前,小肠的重量及长度占胃肠总重及总长的百分比高,小肠生长发育的速度超过胃和大肠。3周龄后,大肠的重量及长度占胃肠总重及总长的百分比增高,尤其在4至8周龄时,由于植物性饲料的刺激作用,使大肠,特别是盲肠的结构和机能发生了明显的变化。仔兔胃内消化有着与仔猪相类似的一段机能发育不全期,2周龄内的仔兔胃内缺乏游离盐酸,对蛋白质不能消化。3周龄的仔兔胃内均已出现游离盐酸,对蛋白质也开始有较弱的消化力,4周龄时,仔兔胃内的酸度和消化力已达断奶后幼兔的水平,6周龄时胃液pH已达成年兔胃液pH的稳定水平。  相似文献   

4.
Selection for hyperprolific sows, as a means of increasing litter size and profit, has resulted in an increased number of low‐birthweight (LBW) piglets. These LBW piglets might suffer from increased morbidity and mortality during the early neonatal period. In addition, they show reduced growth performance, meat and carcass quality, which leads to an important economic loss for the farmer in the post‐natal period. Therefore, nutritional interventions can be undertaken to prevent and rear LBW piglets. In the first part of this review, the preventive strategies at the sow level will be discussed. Approaches in preventing LBW piglets are to optimize the intrauterine environment via supplementing the sow during gestation. In the second part of this review, the interventions at the piglet level will be described. To increase the survival and growth rates of LBW piglets, one must focus on ensuring adequate colostrum and milk intake. Interventions include supplementing piglets, split nursing, split weaning and cross‐fostering. Additional interventions increasing the probability of optimal post‐natal food intake will be discussed.  相似文献   

5.
It is acknowledged that the most critical period of rabbit post natal development comprises the first 10–15 days after weaning, when the animals are most susceptible to gastrointestinal infections and at greatest risk of a fatal outcome. Detailed information on rabbits' weaning is provided. The advantages and disadvantages of early weaning (under 23 days of age) are summarised. Regardless of the numerous reports, the effects of early weaning on the growth and development of bunnies and the physiological status of rabbit does are contradictory. The morphological changes in rabbit digestive tract related to weaning – development of intestinal mucosa, height of villi, crypt depth and villus height to crypt depth ratio – are described in detail. The review also goes over several functional changes in rabbits' organism during weaning: blood cholesterol, triglycerides, α‐amylase, lysozyme, complement, triiodothyronine and thyroxine concentrations, and the time course of epidermal growth factor in the milk of lactating does. Based on published research reports, both ours and of other authors, we suggest that from a physiological point of view, the early weaning of rabbits is not fully justified at present. Nevertheless, the increasing market demand for rabbit meat makes early weaning an attractive alternative for farmers and necessitates further studies on the optimisation of weaning in this species.  相似文献   

6.
猪的心、肝、肺、脾、肾五脏器的发育早晚直接影响着其它部位的生长发育的快慢.运用异速生长方程分析了舍饲型合作猪内脏器官的生长发育规律.结果表明:肝脏和肺脏的增重迅速,肾脏和心脏次之,脾脏较慢;肺脏和肾脏的相对生长速度较快,其次为心脏和脾脏,肝脏较慢;各内脏器官占体重百分比为:肝脏>肺脏>肾脏>心脏>脾脏;异速生长方程拟合的内脏器官生长强度为:心脏(b=1.120)>脾脏(b=0.974)>肺脏(b=0.973)>肾脏(b=0.9520)>肝脏(b=0.726),心脏属于晚熟器官,脾脏、肺脏和肾脏属于中熟器官,肝脏属于早熟器官.为保护合作地方品种,进一步开发利用优良品种提供了数据参考.  相似文献   

7.
本试验旨在研究口感化开食料对蒙贝利亚×荷斯坦杂交犊牛生长性能、胃肠道指标及瘤胃发酵参数的影响。选取20头健康新生蒙贝利亚×荷斯坦杂交犊牛,随机分为2组,每组10头牛,2组分别饲分别饲颗粒化开食料和口感化开食料。试验期10周,所有犊牛第3天开始饲喂开食料,第8周断奶。结果表明:1)2组犊牛的生长性能无显著差异(P>0.05),口感化开食料组的断奶后开食料干物质采食量比颗粒化开食料组高31.28%(P=0.081)。2)2组的瘤胃液pH、氨态氮和总挥发性脂肪酸含量及乙酸、丙酸、丁酸比例均无显著差异(P>0.05)。3)2组的肠道消化酶活性及内脏器官和胃肠道发育指标均无显著差异(P>0.05)。4)口感化开食料组犊牛在哺乳期的腹泻发病率比颗粒化开食料组低16.78%。由此可见,与饲喂颗粒化开食料相比,饲喂口感化开食料对断奶后蒙贝利亚×荷斯坦杂交犊牛开食料干物质采食量的影响存在差异趋势,能够减少犊牛哺乳期腹泻发病率,但对瘤胃发酵参数无显著影响,对胃肠道指标无不利影响。  相似文献   

8.
Morphological studies of the gastrointestinal tract of blue‐and‐yellow macaws (Ara ararauna) are scarce. In view of the paucity of information regarding the digestive tract of macaws, this study aims to describe the gross anatomical features (oesophagus to cloaca) as part of a broad study of the gastrointestinal tract (GIT) of these birds. Three animals (two males and one female) adult macaws were anatomically dissected from the oropharynx to the cloaca to expose the GIT. The oesophagus was identified as a muscle‐membranous tube continuous with the crop, which was intimately attached to the skin. The internal longitudinal folds of the cervical oesophagus were sparser cranial to the crop and less evident compared to the portion caudal to the crop. The duodenum began in the pylorus and was grey‐coloured exhibiting a large lumen. The jejunum was formed by loops in a spiral‐fashion model supported by mesojejunum. The ileum was also composed by small loops and was continuous with the colo‐rectum forming the large intestine, because the caeca were absent. The large intestine was short, median in position, suspended in the dorsal wall of the abdominal cavity by mesentery and ended in the cloaca. The GIT was similar to the basic patterns in birds, in general, and also presented new unreported morphological data that might be important when studying nutrition and health of the macaws.  相似文献   

9.
In the last decades, selection for improved prolificacy has resulted in higher litter sizes and has thereby increased the proportion of low birthweight (LW) piglets. It is well documented that LW piglets have lower growth performance, muscle accretion and poor carcass quality. However, little is known about the relations of birthweight with subsequent reproductive performance in gilts. This study investigated the effects of birthweight on reproductive tract and ovarian follicle development in 150‐day‐old gilts. Twenty eight female pigs of different birthweight ranges (high‐HW: 1.8–2.2 kg; low‐LW: 0.8–1.2 kg) from higher parity commercial sows were reared until 150 days of age, and their body weights were recorded at weaning, end of nursery and end of the grower‐finisher phase. The animals were killed and their reproductive tracts collected for biometrical and histomorphometrical analysis. LW gilts showed significantly lower body weights and growth rates during all phases of production compared to their HW counterparts (p < .01). Most biometrical measurements of the reproductive tract were similar between the experimental groups, except vaginal length and the gonadossomatic index (relative ovarian weight), which were affected by birthweight class (p < .05). LW females also showed fewer medium size (3–5 mm; p < .01) ovarian follicles, pre‐antral follicles (p < .07) and more atretic follicles per ovarian cortex area (p < .05). Therefore, besides the effects on post‐natal growth performance, birthweight affects vaginal length and the follicular dynamics process, which may impair the reproductive performance of replacement gilts.  相似文献   

10.
[目的]探索犊牛早期(3月龄)断奶的可行性,为推广犊牛早期(3月龄)断奶技术提供依据,增加养殖企业的经济效益成本。[方法]试验选取出生后3月龄的西门塔尔犊牛,进行断奶饲养,测量断奶后不同日龄的体重及体尺指标,分析其生长发育情况,并对体重及体尺进行相关性分析。[结果]西门塔尔犊牛断奶后增重快速,断奶后90天,犊牛平均体重达到269.67kg,断奶后平均总增重达到101.54kg,全程日均增重为1128.22g。断奶后90天与断奶后30天比较,体斜长、体高、胸宽、胸深、胸围、腹围、臀围均呈现增加的趋势,其中增长较快的是腹围,其次是胸围,分别增加了19.0cm,14.67cm。体重与体斜长、体高、胸宽、胸深、胸围、腹围、臀围均呈正相关,其中体重与体斜长、体高、胸深、胸围、腹围呈极显著相关(p<0.01)。[结论]犊牛早期(3月龄)断奶后犊牛生长发育情况较好,犊牛早期(3月龄)断奶具有较强的可行性,可大范围推广。  相似文献   

11.
12.
The effect of selection for growth rate on relative growth of the rabbit body components was studied. Animals from the 18th generation of a line selected for growth rate were compared with a contemporary control group formed with offspring of embryos that were frozen at the seventh generation of selection of the same line. A total of 313 animals were slaughtered at 4, 9, 13, 20, and 40 wk old. The offal, organs, tissues, and retail cuts were weighed, and several carcass linear measurements were recorded. Huxley's allometric equations relating the weights of the components with respect to BW were fitted. Butterfield's quadratic equations relating the degree of maturity of the components and the degree of maturity of BW were also fitted. In most of the components studied, both models lead to similar patterns of growth. Blood was isometric or early maturing and skin was late maturing or isometric depending on the use of Huxley's or Butterfield's model. Full gastrointestinal tract, liver, kidneys, thoracic viscera, and head were early maturing, and the chilled carcass and reference carcass were late maturing. The retail cuts of the reference carcass showed isometry (forelegs) or late maturing growth (breast and ribs, loin, hind legs, and abdominal walls). Dissectible fat of the carcass and meat of the hind leg had a late development, whereas bone of the hind leg was early maturing. Lumbar circumference length was later maturing than the carcass length and thigh length. Sex did not affect the relative growth of most of the components. Butterfield's model showed that males had an earlier development of full gastrointestinal tract and later growth of kidneys than females. No effect of selection on the relative growth of any of the components studied was found, leading to similar patterns of growth and similar carcass composition at a given degree of maturity after 11 generations of selection for growth rate.  相似文献   

13.
为了比较道赛特羊、特克塞尔羊及小尾寒羊的生长发育性能和适应性,试验对3品种羊的初生重、断奶重、体高、体重、体长、胸围、管围等生长发育指标进行测定分析,育肥后进行屠宰测定。结果表明,2个引进品种间初生重和断奶重无显著差异,且均表现出早期生长发育快的特点,其体高、体重等生长发育指标及屠宰性状均高于小尾寒羊,表现出良好的肉用效果和适应性。育肥后无角道赛特羊、特克塞尔羊胴体重、腰肌重、大腿重和眼肌面积显著高于小尾寒羊(P0.05)。  相似文献   

14.
For the last several decades, antimicrobial compounds have been used to promote piglet growth at weaning through the prevention of subclinical and clinical disease. There are, however, increasing concerns in relation to the development of antibiotic‐resistant bacterial strains and the potential of these and associated resistance genes to impact on human health. As a consequence, European Union (EU) banned the use of antibiotics as growth promoters in swine and livestock production on 1 January 2006. Furthermore, minerals such as zinc (Zn) and copper (Cu) are not feasible alternatives/replacements to antibiotics because their excretion is a possible threat to the environment. Consequently, there is a need to develop feeding programs to serve as a means for controlling problems associated with the weaning transition without using antimicrobial compounds. This review, therefore, is focused on some of nutritional strategies that are known to improve structure and function of gastrointestinal tract and (or) promote post‐weaning growth with special emphasis on probiotics, prebiotics, organic acids, trace minerals and dietary protein source and level.  相似文献   

15.
The gastrointestinal tract of the snake has various distinctions from mammals, birds and other reptiles. Five gopher snakes (Pituophis catenifer) were studied in relation to the gross anatomical measurements of visceral organs relative to body length as well as the histology of the oesophagus and the stomach. The oesophagus closely resembles the empty stomach upon gross examination. A small palpable thickening was observed at the junction of the oesophagus with the stomach. In both the oesophagus and the stomach, there were cellular and structural differences observed in the tunica mucosa which can be linked to the feeding habits and natural biology of the snake when compared to those of mammals. Both oesophagus and stomach were lined by simple columnar to pseudostratified columnar epithelium. There were no glands in the wall of the oesophagus. Scattered ciliated triangular cells (brush cells) were present among the columnar epithelial cells in the distal portion of the oesophagus. The stomach can be divided into three portions (proximal, middle and distal). The stomach has a small non-glandular portion with low folds. After this small non-glandular portion, glands started to appear and gradually increase in quantity. The largest quantity of glands appeared in the middle portion of the stomach with more branching folds resulting in a decrease in the lumen diameter. The tunica muscularis increased in thickness at the oesophageal and the pyloric-duodenal junctions. Positive statistical correlations were established in thickness of the tunica muscularis between proximal and distal portions of the oesophagus and the stomach.  相似文献   

16.
The mRNA expression of sodium‐glucose transporter 1 (SGLT1) and fatty acid translocase (CD36) in the gastrointestinal tract of Holstein cattle and Saanen goats before and after weaning was investigated. Before weaning, the expression of both SGLT1 and CD36 was highest in the jejunum, relative to the other parts of the gastrointestinal tract in both species. The expression of SGLT1 and CD36 in the duodenum was second highest in the goats. After weaning, SGLT1 and CD36 expression in the small intestine significantly decreased in both species. The expression of both types of transporters was also detected in the forestomach. From these results, it was concluded that the jejunum is probably the major absorption site for glucose and long‐chain fatty acids before weaning, and that the expression of both types of transporters decreases after weaning in cattle and goats.  相似文献   

17.
Iberian pig is the most abundant Mediterranean swine. The lack of knowledge of the reproductive physiology of Mediterranean genotypes, with predisposition to obesity, led us to evaluate the influence of body condition and metabolic status at weaning on the resumption of follicular growth and the appearance of post‐weaning oestrus. Females failing to display post‐weaning oestrus showed a high decrease in backfat mass during lactation; backfat depth at weaning was therefore lower than in sows becoming in oestrus. Females not bearing oestrus behaviour showed lower plasma leptin levels and higher ghrelin concentrations at weaning. Moreover, these sows evidenced dyslipidemic profile (increased triglyceridemia and cholesterolemia) and mobilization of fat reserves. Hence, changes in metabolic regulation of Iberian pigs may originate large effects on the resumption of ovulatory activity after weaning.  相似文献   

18.
The aim of this work was to evaluate the effect of supplementing the feed ration for lactating sows with the conjugated linoleic acid (CLA) on the growth performance and losses of piglets from birth to weaning. The monitoring comprised 20 litters in control and 20 litters in experimental group of Czech Large White × Czech Landrace hybrid combination sows. The control group was given a standard feed mixture for lactating sows, and experimental group was fed with the feed mixture supplemented with 2% of CLA, from the day of farrowing to the weaning of piglets, that is for the time of 28 days. The results of the experiment indicate the significantly better parameters of the numbers of reared piglets in the experimental group and the related lower level of losses of piglets from birth to weaning (p < 0.01). However, the feed mixture for lactating sows enriched in conjugated linoleic acid had no significant effect on the growth performance of piglets from birth to weaning (p > 0.05). Sows in the experimental group showed earlier onset of post‐partal oestrus after weaning of piglets (p < 0.05). These findings demonstrate that the supplementation of diet for lactating sows with CLA can improve survival of piglets from birth to weaning and shortening of weaning‐to‐oestrous interval in sows.  相似文献   

19.
Lengths of small intestine, caecum, ascending colon and descending colon were measured in intestinal tracts from 103 foetuses, foals and adult horses. Intestinal tracts from 21 of the horses were measured at varying intervals after death. Total intestinal length increased markedly from mid-gestation to one year of age, then showed little increment up to 35 years. Small intestinal length increased most rapidly in the first month of life. Caecal length increased most rapidly from one to six months and length of ascending colon increased most rapidly between one week and one year. Descending colon length increased gradually after birth. Periods of rapid increase in length of various intestinal segments and alterations in the percentage of total intestinal length were associated with periods of rapid body growth and changes in dietary composition. Sex and post mortem interval did not affect intestinal length significantly.  相似文献   

20.
分析探讨口感化及颗粒化开食料对早期断奶羔羊生长和胃肠道发育的影响。选取新生健康的双羔湖羊公羔42只,随机分为两组,分别饲喂颗粒化和口感化开食料,试验期42 d。两组羔羊21日龄之前的采食量、体重和绝对生长的变化趋势相似。21日龄以后,口感化开食料组羔羊的采食量、体重、绝对生长和相对生长均明显高于颗粒化开食料组,42日龄体重、后两周的采食量及15~21日龄的相对生长率在两组间有显著差异(P < 0.05)。口感化开食料还显著提高(P < 0.05)了羔羊42日龄时的育肥指数、体长指数、胸围指数、管围指数和断奶前的瘤胃质量和瘤胃/胴体。以上结果表明,与颗粒化开食料相比,口感化开食料更有利于羔羊早期断奶前后的瘤胃发育、采食量提高、体重和体尺的发育,但对其他胃室及肠道发育没有影响。  相似文献   

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