麻豆av一区二区_爽好多水快深点欧美视频_2021久久国产精品不只是精品_一区二区国产精品_中文字幕欧美区_亚洲欧洲精品成人久久奇米网_欧美精品在线一区二区_中文字幕亚洲字幕_国产精品久久久久久婷婷天堂_国产伦精品一区二区三区免

<ul id="uymak"></ul>

<tfoot id="uymak"></tfoot>

畜牧人

標(biāo)題: Pre-peak feed recommendations for laying hens [打印本頁]

作者: 小馬哥 時(shí)間: 2017-11-9 11:11
標(biāo)題: Pre-peak feed recommendations for laying hens

For hens, the start of the lay period is key, as a relatively high numberof problems can occur that might have a negative impact on their subsequentlaying performance and persistency. The laying percentage increases rapidlyduring the start of the lay period. However, feed intake does not increase at aproportional rate.

The pre-peak phase is defined as the period of time between the arrival ofthe reared hens to the production house, generally between 15-18 weeks of age,and the age that laying hens reach peak egg production, typically between 24-26weeks of age. The beginning of lay is physically a very challenging time forthe young hens. As a result, negative nutrient balances can occur. Potentialproblems are exacerbated when the objectives of the rearing phase, such astarget body weight and high uniformity, are not achieved.

Pre-peak feeding strategy challenge

In order tofacilitate a good start to the hens’ development or to correct the effects ofsuboptimal rearing, nutrient intake should be maximised to prevent themobilisation of body nutrient reserves at the start of the lay period. This canbe done by providing a more concentrated feed – assuming that feed intakecapacity is the limiting factor. Alternatively, the energy content can bereduced in the pre-peak laying period in order to stimulate feed intake –assuming that feed intake capacity is not a limiting factor. While in practiceboth strategies are applied, it is not clear which strategy is the mosteffective.

Besides limitingperformance, the negative nutrient balances that occur at the start of the layperiod can affect liver and bone metabolism. Liver metabolism can be affecteddue to the mobilisation of body fat, and bone metabolism can be affected whenmore calcium has to be metabolised for eggshell formation. In order toalleviate or prevent negative effects, it may be useful to add enrichedpremixes to enhance liver, calcium and/or bone deposition.

The transitionfrom rearing pullet to production is also a period in which the laying hensundergo many changes. These include having to adapt to; being transported, newequipment, new environments (microbial population), light stimulation, the startof production, and feed composition. Including dietary ingredients thatalleviate digestive disorders and improve gut health could therefore help thebirds adapt better to their new environments, and could consequently increasehen performance.

As there isincreasing interest from genetics companies and producers in terms ofprolonging the laying period (from 72 to 90/100 weeks of age), supporting thepre-peak phase is becoming even more important. Trouw Nutrition thereforeconducted a series of research to develop a feeding strategy to maximisenutrient intake and to optimise performance in laying hens during the pre-peakperiod (17-24 weeks).

作者: 小馬哥 時(shí)間: 2017-11-9 11:12
Research and development
The Pre-peak laying hens feed project consisted of 3 trials, in order to test different pre-peak feeding strategies, in order to increase feed/nutrient intake, thereby improving performance and body weight gain and to test two different premixes formulated for either enhancing metabolism or gut health.
The study followed a factorial design with 3 diets x 3 premixes during the pre-peak phase (15-24 weeks). The 3 diets consisted of a control diet, an enriched diet with higher levels of nutrients, and the re-named ‘Pre-peak diet’. The 3 premixes consisted of a standard commercial premix, Premix 1 (a premix with higher levels of minerals and vitamins E, B and C) and Premix 2 (the standard premix with Selko Presan – gut health additive).
Table 1 summarises the treatments and phases used during the trial.
Table 1 - Pre-peak trial design evaluating macro nutrient density andpremix composition.
Week 15-24 Treatment Week 25-28 Week 29-32
1 Control diet Standard Premix Control diet Control diet
2 Control diet Test Premix 1 Control diet Control diet
3 Control diet Test Premix 2 Control diet Control diet
4 Enriched diet Standard Premix Control diet Control diet
5 Enriched diet Test Premix 1 Control diet Control diet
6 Enriched diet Test Premix 2 Control diet Control diet
7 Pre-Peak diet Standard Premix Control diet Control diet
8 Pre-Peak diet Test Premix 1 Control diet Control diet
9 Pre-Peak diet Test Premix 2 Control diet Control diet
The 1,408 ISA Brown laying hens in the trial were housed in 2 collective rooms. Each of the 9 treatments included 7 replicates of 22 hens. Layers were selected in the rearing house based on a target bodyweight of 100 grams less than breeding company recommendations (at 15 wks of age). In order to increase the challenge on the flock without affecting performance, light stimulation was provided to the laying hens upon arrival to the PRC (at 15 wks of age), and they were kept at an elevated temperature (26°C at bird level, and 24°C in the room).
According the results obtained in this trial (Table 2), both during and after the pre-peak period (19-24 weeks), increasing diet density, using enriched diet treatments, had no beneficial effect on egg size or production.

作者: 小馬哥 時(shí)間: 2017-11-9 11:12
Table 2 - Performance results.
19 - 24 weeks Production phase: 19 to 24 weeks
Egg Prod., % Egg Weight, g Egg Mass, g FCR, g/g
Control 74.21 51.70b 39.51b 3.343
Enriched diet 75.19 51.87b 39.99ab 3.295
Pre-Peak diet 77.80 52.87a 42.02a 3.194
Control: Premix 1 76.96abc 51.68 40.81abc 3.000abc
Control: Premix 2 73.89bc 52.21 39.50bc 3.324abc
Control: Standard 71.79c 51.19 38.22c 3.705ab
Enriched diet: Premix 1 72.55bc 51.46 38.35c 3.860a
Enriched diet: Premix 2 74.44bc 51.41 39.46bc 3.433abc
Enriched diet: Standard 78.59ab 52.76 42.14ab 2.593c
Pre-Peak diet: Premix 1 77.34abc 52.88 41.70abc 3.576ab
Pre-Peak diet: Premix 2 81.63a 52.75 44.02 a 2.833bc
Pre-Peak diet: Standard 74.41bc 52.98 40.34abc 3.171abc

19 - 32 weeks Production phase: 19 to 32 weeks
Egg Prod., % Egg Weight, g Egg Mass, g FCR, g/g
Control 86.45b 56.46 49.66b 2.577
Enriched diet 86.56b 56.26 49.53b 2.525
Pre-Peak diet 89.19a 56.78 51.41a 2.494
Control: Premix 1 87.16bc 56.26 49.78bcd 2.440abc
Control: Premix 2 86.89bcd 56.75 50.14bc 2.557abc
Control: Standard 85.31cd 56.37 49.07cd 2.733ab
Enriched diet: Premix 1 84.40d 56.08 48.20d 2.791a
Enriched diet: Premix 2 86.77bcd 56.26 49.77bcd 2.575abc
Enriched diet: Standard 88.49bc 56.44 50.63bc 2.210c
Pre-Peak diet: Premix 1 89.17ab 56.55 51.22ab 2.667abc
Pre-Peak diet: Premix 2 91.74a 56.37 52.42a 2.331bc
Pre-Peak diet: Standard 86.67bcd 57.43 50.59bc 2.485abc

When hens were fed with the Pre-peak diet, feed intake increased and, as a result, the intake of crude protein, calcium and phosphorous increased (Table 3). At the onset of production, the hens fed the Pre-peak diet had higher overall egg weight. These same hens also had an overall higher egg production rate and egg mass.
Table 3 - Feed and nutrient intake. 19-24 weeks Treatments
Diet Feed Intake, g/d CP Intake, g/d Ca Intake, g/d Dig. P Intake, g/d
Control 97.94b 16.65b 3.624b 0.3036b
Enriched diet 92.87c 16.72b 3.608b 0.3023b
Pre-peak diet 103.6a 18.64a 3.987a 0.3371a

作者: 小馬哥 時(shí)間: 2017-11-9 11:12
本帖最后由小馬哥于 2017-11-9 11:16 編輯

Pre-peak laying hen diets

From the period when the laying hens are introduced inthe production facilities until peak production (18-24 weeks), according theTrouw Nutrition R&D outcomes it can be concluded that feeding hens thePre-peak diet during the pre-peak period (18-24 weeks old) will ensure highernutrient intake and as a consequence, obtaining +2 eggs/hen, in the period from19-32 weeks old, reduced feed costs, around and early onset of lay. The diet stimulates a2-week early onset of lay. Feeding hens with Pre-peak diets with Presan willprovide the optimal performance in this period.

作者: 小馬哥 時(shí)間: 2017-11-9 11:14
Recommendations Pre-peak laying hen diets
Developed by Trouw Nutrition, the Pre-peak concept can improve the performance of hens and the profitability of your business and is now available in the NutriOpt precision feeding system. The NutriOpt Pre-peak recommendations use an exclusive matrix to customise Pre-peak diets according to the requirements of laying hens during the pre-peak period (18-24 weeks old). This results in a higher supply of nutrients and a better onset of lay, improving the performance of hens, while reducing feed costs.
Author: Trouw Nutrition

歡迎光臨畜牧人 (http://www.cqnsfzw.com/)