Growth, food intake and development in broiler cockerels raised to maturity

1985 ◽  
Vol 41 (2) ◽  
pp. 239-245 ◽  
Author(s):  
Nicola J. Prescott ◽  
C. M. Wathes ◽  
J. K. Kirkwood ◽  
G. C. Perry

ABSTRACTThe food intake, growth and development of Ross broiler cockerels were recorded from 1 day old to maturity. At regular intervals, the body composition of these birds was determined and the eviscerated carcasses were chemically analysed. Allometric relationships of component weights and live weight were examined. Historical comparisons with fowl reared during the last 60 years did not reveal any significant changes in the pattern of development, despite faster absolute growth rates and heavier mature weights.

1983 ◽  
Vol 100 (3) ◽  
pp. 681-687 ◽  
Author(s):  
A. S. Davies

SUMMARYSelected data of McMeekan (1940, 1941) were reanalysed to compare the proportions and distribution of tissues, and the weights of some organs, in pigs growing at different growth rates due to differing levels of nutrition. The effects of variation in fat content were excluded, and the distribution of tissues was compared at the same total weight for each tissue, by allometric regressions. Except for components of the head and neck, and the stomach, the results do not support a concept of retardation of development by poor nutrition of those parts of the body with the highest relative growth rates.


1973 ◽  
Vol 80 (1) ◽  
pp. 17-27 ◽  
Author(s):  
R. C. Kellaway

SummaryGrowth rates, chemical composition of the body and wool production were measured with wethers and ewes from two genotypes of sheep grazing at two planes of nutrition. The nutritional treatments were applied after weaning at 12 kg live weight. Animals were slaughtered at 6 kg intervals between 12 and 54 kg live weight.Dorset Horn × (Border Leicester × Merino) lambs grew 57% faster than South Australian Merino lambs before weaning, produced 22% more wool and contained more fat at weaning.Post-weaning growth rates on the high and low planes of nutrition were 168 and 78g/day for Merinos and 183 and 116 g/day for Cross-breds. Despite these differences, there was virtually no effect on body composition. Sheep which were starved and re-grown also had a similar body composition to sheep grown continuously.There was, however, a nutritional effect on wool production. On the high plane of nutrition the rate of wool production was 22% higher than on the low plane of nutrition.After weaning there were only small differences in the growth rate of the two genotypes but the Merinos grew 30% more wool than Cross-breds on the high plane of nutrition and 39% more wool on the low plane of nutrition. Genotype differences in the fat and protein content of the empty body were small, but Merinos contained more ash, Ca, P and Mg.After weaning the normal pattern of allometric growth was reversed; at 18 kg live weight the sheep contained a lower proportion of fat and higher proportion of water than at 12 kg live weight. Above 18 kg live weight normal allometric growth was resumed. The fat-free empty body became progressively less hydrated but the ratio of protein: ash remained constant at 79:21 for Merinos and 81:19 for Cross-breds.There was a trend towards ewes being fatter than wethers, but this was only significant with Merinos. Other sex differences in body composition, body growth and wool growth were not significant.


Author(s):  
B.W. Butler-Hogg ◽  
I.D. Johnsson

The generally accepted view is that, in sheep and cattle, plane of nutrition (as indicated by growth rate) can influence body composition; the higher the rate of gain the greater the fatness at a particular live or carcass weight. However, exceptions to this view can be found which demonstrate that the effective protein: energy ratio of the diet can exert a considerable influence on the composition of live weight gain. Unfortunately most studies which have considered the effects of growth rate on composition (either directly or as a consequence of some treatment which resulted in different growth rates) have described their animals in terms of chemically determined protein, fat, ash and water. To assess the potential economic impact of different growth rates on body composition and the distribution of fat throughout the body requires dissection data, describing the animal in terms of lean, bone and individual fat depots. In this experiment the dissected composition of 44 Hampshire Down x Mule ewe lambs was determined in animals which had followed planned growth paths involving periods of high (H) and low (L) growth.


1990 ◽  
Vol 51 (2) ◽  
pp. 375-387 ◽  
Author(s):  
B. P. Mullan ◽  
I. H. Williams

ABSTRACTIt is common for sows in commercial practice to lose body weight during lactation and if the loss is excessive then performance may be impaired. However, there is little information on the composition of this loss of body weight. In a 2 × 2 factorial experiment gilts were given daily either 2·7 (H) or 1·5 (L) kg food during gestation and either a high (H) (mean intakes of 3·4 and 4·9 kg/day for the H-H and L-H groups, respectively) or low (L, 2·0 kg/day) food intakes during a 31-day lactation. Seventy-three animals were slaughtered at various stages over all treatments and body composition determined by chemical analysis. The content of lipid (Li, kg) and protein (Pr, kg) in the empty body were closely related to live weight (LW, kg) and depth of backfat measured by ultrasound (P2, mm); Li = 0·381 LW + 1·042 P2 - 31·099 (R = 0·95) and Pr = 0·11 LW - 013 P2 + 4·46 (R = 0·67). Prediction equations were used to predict the composition of animals from a previous experiment (Mullan and Williams, 1989). Increasing food intake prior to farrowing increased the amount of lipid (67 v. 38 kg), protein (20 v. 17 kg), water (73 v. 63 kg) and ash (5 v. 4 kg) in the empty body at farrowing. For sows given 2·0 kg/day food during lactation about half of the total loss of body weight was lipid (835 and 570 g/day for the H-L and L-L groups, respectively) and proportionately 0-10 was protein tissue (165 and 125 g/day, respectively). When sows were fed to appetite the heaviest animals lost both lipid (520 g/day) and protein (130 g/day) whereas animals in the L-H group maintained their lipid reserves but lost 65 g protein per day. This study demonstrates the considerable amounts of lipid and protein which may be mobilized by the sow during lactation to buffer the nutritional stress through a low intake of food. The body composition of the sow during the first lactation can be accurately predicted from live weight and depth of backfat.


2001 ◽  
Vol 73 (2) ◽  
pp. 305-311 ◽  
Author(s):  
J. R. Webster ◽  
I. D. Corson ◽  
R. P. Littlejohn ◽  
S. K. Martin ◽  
J. M. Suttie

AbstractYoung male red deer follow a seasonal growth pattern that can be shifted by altering the photoperiod they experience. An increase in photoperiod to 16 h of light per day (16L : 8D) during winter advances the onset of rapid growth and high food intake that normally commences in spring. These changes are associated with increased growth hormone (GH) and insulin-like growth factor-1 (IGF-1) secretion. The GH/IGF-1 axis is acutely sensitive to the level of nutrition and the relative rôles of photoperiod and nutrition in determining the spring IGF-1 rise is unknown. The present experiment set out to examine this by exposing two groups of deer (no. = 8 per group) to a photoperiod shift during their 1st year of life (16L : 8D from 2 June), designed to cause accelerated growth and increased food intake after approximately 7 weeks. However, after 6 weeks the food intake (pellets containing 11 MJ metabolizable energy and 160 g crude protein per kg dry matter (DM)) of one group (LDRES) was clamped, thereby preventing the intake component of the response. The intake of the other group (LDAL) remained ad libitum for a further 12 weeks until 6 October, when the experiment concluded.During the first 6 weeks of 16L : 8D, growth rate (118 (s.e. 15·4) g/day) and food intake (1·37 (s.e. 0·031) kg DM per head per day) did not differ between the groups. Food intake following the clamp in LDRES averaged 1·40 (s.e. 0·015) kg per head per day. The intake of LDAL increased 2 weeks after the clamp and thereafter was higher than LDRES (P < 0·001). Food intake of LDAL averaged 2·13 (s.e. 0·051) kg during the nutritional clamp period. Growth rates increased in both groups during the first 3 weeks of the clamp, averaging 237 (s.e. 25·0) g/day, then growth slowed in LDRES and live weights diverged. Growth rates until the end of the experiment (147 (s.e.23·0) g/ day v. 299 (s.e. 12·5) g/day, P < 0·001) and mean live weight over the last 5 weeks of the experiment were lower (P < 0·05) in LDRES than LDAL, weights reaching 88·3 (s.e. 1·86) kg and 97·9 (s.e. 2·74) kg respectively on the final sampling date. Metatarsal bone length grew more in LDAL than in LDRES (3·1 v. 2·2 cm, s.e.d. = 0·23, P < 0·01). Prior to the nutritional clamp, mean plasma prolactin and IGF-1 concentrations increased at 3 and 6 weeks after 16L : 8D respectively, in both groups. Prolactin concentrations were lower in LDRES than LDAL on two occasions, at weeks 3 and 7 after the onset of the nutritional clamp, and IGF-1 concentrations were lower in LDRES than LDAL (676 v. 872 ng/ml, s.e.d. = 73·8, P < 0·05) over the last 7 weeks of sampling.In summary, a photoperiodically driven increase in IGF-1 occurred even when the usual associated increase in food intake was prevented. This indicates that the seasonal IGF-1 rise in red deer is not a consequence of the increased food intake, although the latter appears necessary to maintain elevated IGF-1 concentrations. The rise in IGF-1 may therefore be considered as a component of the photoperiodically entrained seasonal drive to grow, and the increase in food intake a response to satisfy the increased energy demand.


1994 ◽  
Vol 124 (suppl_12) ◽  
pp. 2622S-2623S ◽  
Author(s):  
Helen S. Munday ◽  
Kay E. Earle ◽  
Philip Anderson

2021 ◽  
Vol 1 (1) ◽  
pp. 3-10

In dairy cattle breeding, selection and breeding work is widely used in order to transfer the pedigree qualities of parents to the offspring and obtain highly productive young animals. In this regard, in the conditions of «Enbek» LLP in the Akmola region, the growth and development of young Simmental breed depending on the origin was studied. Live weight of Litera line young animals at birth was 33.4 kg, at the age of 6 months-174.9, 12 months-251.8, 18 months-387.1 kg, respectively, Wildfang bull 32.0 kg, 165.5 kg, 251.3 kg, 378.6 kg. The average daily gain between the ages of birth and 6 months was increased. With age, the body parameters, height at the withers, increased from 104.3 cm and 103.5 cm to 125.4 cm and 123.9 cm, respectively, from 6 months to 18 months of young animals. According to the physique indices, we can say that the young Simmental breed is balanced. Only some deviations of the leggy index are observed from the optimal indicators. The index of legginess decreases with age by 7.7%, with indicators of 6 months – by 57%, at the age of 18 months-by 49.3%. The extension index for the period from 6 to 18 months increased by 10.5%, respectively, for 6 months-by 103.3%, for 18 months-by 113.8%. With age and an increase in live weight, the body of young animals lengthens, its width increases, the animal becomes deeper and relatively long-legged. Depending on the origin, we suggest using the Litera bull line, taking into account the growth and development of young animals, and the productivity indicators of bulls.


Author(s):  
M Wan Zahari ◽  
J K Thompson ◽  
D Scott

The effects of plane of nutrition on the body composition of growing sheep are very apparent when animals are compared at the same age following different nutritional histories. These differences are, however, less obvious when animals of the same breed and sex are compared at the same body weight and at present there is some conjecture whether composition is affected by growth rate. This uncertainty is not limited to fat and protein but includes the bone and ash, fraction and the ash composition.The primary objective of this trial was to study the effects of different growth rates achieved by feeding different amounts of the same concentrate diet on the composition of empty-body gain and on the retention of minerals by growing lambs. A secondary objective was to examine the effect of adding supplementary calcium carbonate to the basal diet at the fast rate of growth.


2020 ◽  
Vol 60 (16) ◽  
pp. 1959
Author(s):  
Camila Angelica Gonçalves ◽  
Nilva Kazue Sakomura ◽  
Miryelle Freire Sarcinelli ◽  
Letícia Graziele Pacheco ◽  
Letícia Soares ◽  
...  

Context Genetic improvements in modern strains have led to continuous increments in broiler growth rates, which, as a consequence, have resulted in higher economic returns for broiler producers over the last decades. Aim The present study was conducted to characterise the potential growth of the body and feathers of Cobb 500, Hubbard Flex and Ross 308 male and female broilers, as well as to assess the changes in chemical composition that occur up to 16 weeks of age. Methods Birds were fed isoenergetic diets divided in four phases and formulated to marginally exceed the nutritional requirements of the strains throughout the growing period. They were maintained in a controlled environment so as not to limit growth. A dual energy X-ray absorptiometry (DXA) scanner was used to follow the in vivo body composition of 12 broilers of each strain and sex (total of 72 broilers), and the feather weight and composition was determined in four birds of each strain and sex selected at intervals during the growing period (total of 288 broilers) through comparative slaughter with later chemical analysis. Key results Parameters of Gompertz growth curve to describe the strains were estimated for body and feather weight as well as for the growth of their chemical components. Conclusion Differences in the growth rates between strains were evident, indicating the possible differences in selection methods used by geneticists in the different breeding companies. These genetic parameters would explain part of the variation on broiler´s performance which impacts on the way they should be fed and housed during growth. Implications The accurate description of genetic growth potential is useful information to be associated with factorial models that predict nutritional and feed intake requirements of birds. The main advantage of DXA technology is to decrease the variation of body deposition on the Gompertz model, resulting from the use of the same bird throughout its life. Despite the speed of obtaining chemical values of the body, the method is unsuitable for measuring the growth of feathers, which is also important data to be collected and related to the broiler strains.


1970 ◽  
Vol 75 (1) ◽  
pp. 19-26 ◽  
Author(s):  
R. P. Andrews ◽  
E. R. Ørskov

SUMMARY1. In an experiment with ninety-nine lambs the effects on the body composition of male and female lambs were examined when five diets containing different concentrations of crude protein (in the range 10–20%) were given at three levels of feeding and lambs were slaughtered at two live weights (27·5 and 40 kg).2. With lambs slaughtered at 27·5 kg there were significant increases in the rate of both nitrogen and fat retention with increases in levels of feeding. There were also linear increases in the rate of protein deposition and decreases in fat deposition with increases in the concentration of crude protein. This effect was particularly marked at the high level of feeding.3. With lambs slaughtered at 40 kg live weight there were also linear increases in fat and in nitrogen deposition with increasing feeding level but the effect of increasing the protein concentration on increases in nitrogen retention departed from linearity.4. While at 27·5 kg there were no significant effects of feeding level on nitrogen and ether-extract content of the bodies at slaughter, with animals slaughtered at 40 kg there was a significant linear decrease in ether-extract content with increasing feeding level and a corresponding linear increase in nitrogen content with increased level of feeding.5. Male lambs deposited more nitrogen and less fat than females. This was true of both rate of deposition and of carcass composition at 40 kg live weight.


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