The effect of feed protein content on the uniformity of production in laying hens

2018 ◽  
Vol 58 (12) ◽  
pp. 2308
Author(s):  
Hilda Cristina Palma Bendezu ◽  
Nilva Kazue Sakomura ◽  
Euclides Braga Malheiros ◽  
E. P. Silva ◽  
Robert Mervyn Gous

The objective of this research was to describe the effect of dietary protein content on the uniformity of egg production in ISA-Brown and Hy-Line laying strains. Six dietary protein levels (120–220 g protein/kg feed) were each fed to 16 individually caged hens, per treatment and strain, during the first 6 weeks of the trial from 28 weeks of age. During the second phase, from 35 weeks, only one feed was offered, this containing 175 g protein/kg. Egg production, feed intake, egg weight, egg output and changes in bodyweight were measured. Some birds were sampled before the trial began, after 6- and again after 10-weeks for carcass analysis. Maximum egg output differed between strains but the marginal response to dietary protein was the same in both strains, the coefficients of response being 220 mg protein/g egg output and 9.0 g per kg bodyweight. The coefficient of variation in egg output was low in both strains fed the highest protein feed but increased as the dietary protein level dropped, with the biggest increase occurring in outputs between birds fed 140 and 120 g protein/kg. These increases were particularly marked in the ISA strain, being almost twice as high as those of the Hy-Line strain. Similarly the lowest coefficients of variation in daily food intake were on the highest protein feeds, with a 2- to 3-fold increase on the lowest dietary protein levels, but with both strains in this case showing similar degrees of uniformity. Variation in body lipid content was higher in the ISA strain between dietary treatments. Uniformity in egg output is increased at the highest intakes of dietary protein because the amino acid requirements of an increasing proportion of the population are met by these higher protein contents. As the protein supply becomes marginal and then deficient uniformity is decreased not only because the most demanding individuals cannot consume sufficient to achieve their potential, but also because birds differ in their ability to deposit excess energy as body lipid when attempting to consume sufficient of a feed limiting in protein. This ability to fatten differs not only between individuals within a population but between strains, as shown in the differences between the two strains used in this trial.

2000 ◽  
Vol 51 (6) ◽  
pp. 779 ◽  
Author(s):  
D. Balnave ◽  
R. J. Gill ◽  
X. Li ◽  
W. L. Bryden

IsaBrown pullets were obtained from a commercial breeder at 15 (Expt 1) and 16 (Expt 2) weeks of age and housed in either single-bird or multiple 5-bird cages in a high rise, windowless layer house in which temperatures were maintained below 30˚C by computerised control of fans and evaporative cooling pads. In Expt 1, they were fed either a grower diet or a pre-layer diet consisting of the grower diet containing additional calcium to 18 weeks of age and then maintained during lay to 56 weeks of age on diets containing either 160 or 180 g crude protein (CP)/kg. In Expt 2, they were fed the grower diet to 19 weeks of age and then 1 of 5 diets similar in all ingredients except that the lysine concentration varied between 7.35 and 8.95 g/kg in increments of 0.4 g/kg. The L-lysine HCl supplements were added in lieu of solka floc, an inert cellulose supplement. In Expt 1, mortality was low (2.25%), peak egg production was high (95–98%), and the mean rate of lay at 56 weeks of age was above 88%. The diet fed prior to lay had no significant effect on production during lay. Feed intake and egg production were similar for hens fed both dietary protein levels during lay, and egg weight and egg mass output were greater for hens fed the diet containing 180 g CP/kg. Hens in multiple-bird cages ate significantlyless feed for a significantly smaller daily egg mass output. In Expt 2, increasing the dietary lysine concentration significantly reduced feed intake and significantly increased lysine intake, egg shell breaking strength, and albumen height. Multiple-caged hens had a significantly lower hen-housed egg production as a result of a 7-fold increase in mortality compared with hens in single cages, due mainly to cannibalism. The daily lysine requirement formaximum egg production approximated 940 mg for hens in single cages and 975 mg for hens in multiple-bird cages.


2000 ◽  
Vol 80 (4) ◽  
pp. 633-642 ◽  
Author(s):  
Palle V. Rasmussen ◽  
Christian F. Børsting

The effect of different and shifting dietary protein levels on hair growth and the resulting pelt quality in mink was studied. Two groups of pastel female mink were fed either 59% (high protein, HP) or 40% (low protein, LP) of metabolisable energy (ME) from protein during pregnancy and lactation. Shortly after weaning, kits from females fed the LP diet were put on a new LP diet (21% protein of ME). Kits from females fed HP were randomly distributed to four experimental groups fed a new HP diet (34% protein of ME) and three of these groups were shifted to diets with 21% protein at different times during June until September. Skin biopsies were taken at 4, 6, 23 and, 29 wk of age. Histological techniques and computer-assisted light microscopy were used to determine the ratio of activity (ROA) of underfur and guard hairs, respectively, defined as the number of growing hairs as a percentage of the total number of hairs. The hair fibre length and thickness were determined by morphometric methods and correlated with fur properties of dried pelts judged by sensory methods. It was documented that 40% of ME from protein during pregnancy and lactation was sufficient for mink kits to express their genetic capacity to produce hair follicles. In males, a reduced protein level from the age of 15 wk or 22 wk until pelting disturbed moulting, indicated by a low ROA of underfur hairs at 23 wk, and consequently reduced the growth and development of the winter coat. A constantly low protein level from conception until the age of 29 wk did not disturb moulting, but led to a reduction of primeness and especially of the underfur length and fibre thickness of the winter coat. A low protein level from the age of 9 wk only reduced the thickness of the underfur fibres. Hair growth, final fur volume, and general quality of the winter coat of males were influenced negatively and to the same degree in all groups fed the LP diet in part of the growth period. The number of underfur hairs per area (hair density) of the winter coat was not influenced by the dietary treatment meaning that the protein content of 21% of ME in the LP diet was high enough for the mink to express its genetic capacity to develop hair follicles. However, this low protein content led to a reduction of hair fibre length and hair fibre thickness of the underfur. Overall, this study demonstrated that hair growth and hair properties in pelts are very dependent on the dietary protein supply in the period from 22 wk of age until pelting, irrespective of the supply in the preceding periods. Key words: Fur properties, hair fibres, nutrition, pelage, protein requirement


1999 ◽  
Vol 77 (11) ◽  
pp. 1822-1828 ◽  
Author(s):  
Andrew G McAdam ◽  
John S Millar

Growth and female maturation appear to be limited by the availability of dietary protein in natural populations of deer mice (Peromyscus maniculatus borealis) in the Kananaskis Valley, Alberta. We examined the effects of dietary protein content on nestling growth rates and sexual maturation of female deer mice in two laboratory experiments. In the first, mice whose mothers were fed a low-protein mixture of sunflower seeds and oats (14% protein) exhibited slow growth prior to weaning and those fed high-protein cat food (30% protein) postweaning showed compensatory growth. Preweaning but not postweaning diet quality affected the proportion of females who were sexually mature at 42 days of age. Therefore, while deficient nestling growth can be compensated for, the effects of a low-quality maternal diet during lactation may have lasting effects on the maturation of female offspring. In the second experiment, mice raised on isocaloric diets of 14, 20, and 30% protein did not differ in growth as nestlings or juveniles. Differences among the three diets in the proportion of mature females at 42 days did not correspond to dietary protein levels as predicted. Dietary protein content from 14 to 30% appear to be sufficient for juvenile mice raised in captivity.


1971 ◽  
Vol 11 (49) ◽  
pp. 161 ◽  
Author(s):  
JK Connor ◽  
HW Burton

Two experiments examined the effects of protein restriction in the growing period on the production of egg type pullets. The protein levels of diets fed in the growing period were 15, 13, and 11 per cent. The treatments were incorporated in factorial designs with nutritional treatments in the laying period involving diet protein levels of 17, 15, and 13 per cent and, for one of the experiments, with housing densities of either 4 sq. ft. or 2 sq. ft. per bird. Restriction of protein during the growing period retarded growth and delayed sexual maturity, but neither of the levels of restriction examined increased subsequent laying performance. Eggs lost due to delays in the onset of production were not compensated for by increases in subsequent production and egg weight was generally depressed by protein restriction. The pattern of egg production was altered by restriction. A 13 per cent protein layer diet introduced at point of lay also reduced bodyweight gain and delayed age at sexual maturity. Interactions between nutritional and housing treatments in the growing and laying periods were apparent in egg production and egg weight.


1977 ◽  
Vol 38 (1) ◽  
pp. 39-45 ◽  
Author(s):  
U. Satyanarayana ◽  
B. S. Narasinga Rao

1.Six groups of rats were given diets containing protein at three levels (SO, 100 and 200 g/kg), with and without nicotinic acid. After 4 weeks on these diets some key enzymes of the tryptophan and nicotinic acid-NAD pathway, liver nicotinamide nucleotide concentration, and urinary metabolites of tryptophan and nicotinic acid were studied.2.Liver nicotinamide nucleotide levels were lower in rats given the diet with 50 g protein/kg as compared to those in rats given diets with 100 and 200 g protein/kg. The addition of nicotinic acid to the diet resulted in a significant increase in the levels of nicotinamide nucleotides only in rats given 50 g protein/kg diet but not in those given either 100 or 200 g protein/kg diet.3.Liver tryptophan oxygenase (EC 1.13.1.12) activity increased with increasing dietary protein level. Nicotinic acid in the diet had no effect on its activity.4.Quinolinate phosphoribosyltransferase (EC 2.4.2.a) activity in liver was inversely related to dietary protein level, and nicotinic acid in the diet had no effect on its activity.5.Liver nicotinate phosphoribosyltransferase (EC 2.4.2.11) activity and kidney picolinate carboxylase (EC 4.1.1.45) activity were not altered either by dietary protein level or nicotinic acid in the diet.6.The addition of nicotinic acid to the diet resulted in increased excretion of W-methylnicotinamide at all dietary protein levels.7.The inverse relationship between protein level in the diet and liver quinolinate phosphoribosyltransferase activity, the rate-limiting enzyme of the tryptophan-NAD pathway suggests that the efficiency of conversion of tryptophan to NAD is related to protein level in the diet, the efficiency decreasing with an increase in the level of dietary protein.


2010 ◽  
Vol 299 (6) ◽  
pp. R1720-R1730 ◽  
Author(s):  
Laure Chevalier ◽  
Cécile Bos ◽  
Dalila Azzout-Marniche ◽  
Dominique Dardevet ◽  
Daniel Tomé ◽  
...  

We had previously observed that drastic increases in protein consumption greatly modified hepatic protein anabolism in rats, but the confounding effects of other macronutrient changes or a moderate protein increase to generate the same modifications have not yet been established. This study examined the metabolic and hormonal responses of rats subjected to 14-day isoenergetic diets containing normal, intermediate, or high-protein levels (NP: 14% of energy, IP: 33%, HP: 50%) and different carbohydrate (CHO) to fat ratios within each protein level. Fasted or fed rats ( n = 104) were killed after the injection of a flooding dose of 13C-valine. The hepatic protein content increased in line with the dietary protein level ( P < 0.05). The hepatic fractional synthesis rates (FSR) of protein were significantly influenced by both the protein level and the nutritional state (fasted vs. fed) ( P < 0.0001) but not by the CHO level, reaching on average 110%/day, 92%/day, and 83%/day in rats fed the NP, IP, and HP diets, respectively. The FSR of plasma albumin and muscle did not differ between diets, while feeding tended to increase muscle FSR. Proteolysis, especially the proteasome-dependent system, was down-regulated in the fed state in the liver when protein content increased. Insulin decreased with the CHO level in the diet. Our results reveal that excess dietary protein lowers hepatic constitutive, but not exported, protein synthesis rates, independently of the other macronutrients, and related changes in insulin levels. This response was observed at the moderate levels of protein intake (33%) that are plausible in a context of human consumption.


1985 ◽  
Vol 65 (1) ◽  
pp. 113-124 ◽  
Author(s):  
F. G. PROUDFOOT ◽  
H. W. HULAN ◽  
K. B. McRAE

A factorial experiment was conducted with 3030 chickens of four maternal dwarf genotypes mated with normal males to estimate the effects of age at a photoperiod change from 8 to 12 h (daily) at 140 or 154 days, and two levels of dietary protein (15 or 17%) on general performance, incidence of Fatty Liver Syndrome and monetary returns. Three of the four maternal genotypes performed similarly for most traits measured but one genotype exhibited better feed efficency of egg production, produced more eggs and, although the eggs were smaller resulted in the highest monetary returns. Delaying the increase in photoperiod change retarded sexual maturity and reduced egg weight at 203 days and egg specific gravity at 406 days. The 17% protein diet improved egg production (including hatching eggs), feed efficiency of egg production, egg weights; and female body weights at 154 and 446 days of age were also heavier. Dietary protein levels had no effect on mortality (P > 0.05). Mean monetary returns from the sale of table eggs, hatching eggs and salvage meat in excess of the costs of day-old breeder stock and feed, averaged $1.07 more per bird fed the 17% diet. The progeny test revealed significant differences among genotypes for male mortality, male and female body weights, and feed conversion; however, monetary returns over feed and chick cost were similar. The time of change in photoperiod and dietary treatments had no significant effect on the overall performance of broiler progeny but there was a genotype × parental diet interaction for 43 day female body weights. Key words: Dwarfs, meat breeders, hens, broilers, photoperiods, diets


Crustaceana ◽  
2015 ◽  
Vol 88 (1) ◽  
pp. 82-95 ◽  
Author(s):  
Liying Sui ◽  
Guannan Ma ◽  
Yuangao Deng

Litopenaeus vannamei (Boone, 1931) postlarvae with average initial body weight of 0.089 g were reared in 75-litre PVC tanks for 40 days at salinities of 30 and 60 g l−1. The shrimps were fed compound feed containing protein levels of 35, 40, 45 and 50%, respectively. Salinity had a remarkable effect on growth and survival of L. vannamei juveniles. Higher survival rate and lower growth were observed at 60 g l−1 salinity. Dietary protein level affected the survival and growth of juveniles at both salinities, increased with dietary protein levels in the range of 35 to 45%, but decreased slightly with 50% dietary protein. Broken line analysis showed that the estimated optimal dietary protein levels at salinities of 30 and 60 g l−1 were 45.93 and 46.74%, respectively. Higher salinity resulted in an increased moisture content, ash and crude protein content in the shrimp muscle tissue. The amino acid contents in the shrimp muscle tissue were generally higher at 60 g l−1 salinity and increased dietary protein level led to higher protein content, except with 50% dietary protein. At salinity 60 g l−1, the soluble protein content and activities of glutamic oxalacetic transferase (GOT) and glutamic pyruvic transaminase (GPT) in shrimp muscle tissue were higher, while catalase (CAT) activities were lower. Farming of L. vannamei at a marginal culture salinity (60 g l−1) is feasible though the shrimps were likely exposed to stressful conditions. Reduced growth rate at higher salinity may be attributed to the higher total ammonium (TAN) concentration in the culture medium and extra energy consumption for osmoregulation at hypersaline conditions.


2021 ◽  
Vol 33 (1) ◽  
pp. 45-52
Author(s):  
S. Babangida ◽  
C. O. Ubosi

 Four dietary treatments differing in protein levels were compared to ascertain the protein requirement of laying Japanese quail in a semi-arid environment. One hundred and twenty quails were randomly assigned to four treatments (TI — 22%CR T2 — 20%CP T3 — 18%CP and T4 - I6%CP) in a completely randomized block design Each treatment was replicated thrice with ten quails each. Feed intake, body weight gain, hen day egg production, feed conversion ratio FCR), egg quality and hematological constituents were the response criteria. The study lasted seven weeks. Feed and water were provided ad libitum throughout the experimental period No significant (P> 0.05) effect of dietary protein was observed for feed intake, average body weight gain, hen-day egg production, F CR, dressing percentage and hematological parameters. Average body weight was significantly (P<0,05) enhanced by high dietary protein. Egg weight and Haugh unit were significantly (P<0. 05) better for the groups fed the higher protein levels (20 and 22% CP). Hen-day egg production, albumen index, specific gravity, shell weight and percent shell were not affected (P>0.05) by dietary protein levels. The costs of producing l kg egg in the treatment groups were ₦25926, ₦21007, ₦252.44 and ₦1263./10 for T1, T2, T3 and T4, respectively. It was concluded that about 20%CP is required in the diets of laying Japanese quail under a semi-arid environment of Nigeria.


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