英国的猪和蛋鸡混合生产者火灾后投资未来

英国萨福克郡的猪和禽蛋混合生产者对自由散养鸡生产的前景充满信心。     

The hen's egg: Prediction and reduction of downgrading in large producer groups

British Egg Marketing Board data on the incidence of downgrading in eggs received at packing stations during the second week in each month from April 1960 to March 1968 have been analysed in relation to:

1. the incidence of free‐range, deep‐litter and battery husbandry in flocks from which they came, as estimated by interpolation from annual census data;

2. season, as represented by fundamental and first‐harmonic sine and cosine terms;

3. age‐structure of the flocks, as indicated by the incidence of extra‐small eggs 10 months earlier;

4. time;

5. packing‐station throughput.

It is shown that 93–3 per cent of the variance of downgrading percentage is associated with variation in (i), (ii) and (iii). After these effects had been taken into account there was no significant long‐term time‐trend but there were small effects associated with certain years. There was no significant effect of (v). The regression equation was used to predict the incidence of downgrading in the second week of each month from April 1968 to January 1969; this it did accurately except in May and June 1968, when the downgrading percentage fluctuated to an unprecedented degree following a very cold and a very hot spell of weather.

It is suggested that large producer‐packer groups should systematically collect information on the incidence of downgrading and the percentages of birds of each strain and age‐group, of cages of each type, of nutritional regimes and of egg‐collection methods; and that these data should be analysed to yield (a) forecasts of downgrading incidence and (b) estimates of the effect of each strain, cage‐type, etc. on downgrading incidence, for use when deciding replacement policy.     

浅析蚕种处理的原则及蚕种事故

1　蚕种处理的重要性作为商品之一的蚕种 ,对其质量评价标准过去是以亲代种茧调查成绩为主要考核内容 ,上个世纪 80年代逐步改为直接以蚕种(卵 )本身的性状为主进行考核 ,比较成熟的项目有病毒率、杂交率、最大二日 (实用 )孵化率、总孵化率 4项 ,反映蚁蚕健康度的“绝食生命率”因操作原因尚难统一。病毒率、杂交率成绩取决于饲育期、制种期的技术管理 ,而实用孵化率、总孵化率与产卵后对蚕种实施的各项处理关系更为密切。因蚕种保护、冷藏、浸酸等环节处理失误而导致蚕卵孵化不齐、死卵增加 ,致使蚕种丧失使用价值的事故屡见不鲜。蚕卵阶…     

The chicken egg as a supply of polyclonal antibodies

Polyclonal antibodies can be isolated not only from the blood of immunized mammals but also from the egg yolk of immunized chickens. The advantages of this alternative method are: 1) Birds produce antibodies against highly conserved mammalian proteins. 2) The quantity of antigen needed for an efficient immune response is very low (20-30 micrograms). 3) The use of complete Freund's adjuvant leads to long lasting titers of yolk antibodies yielding a total amount of 65 mg specific antibodies per month. 4) The purification of antibodies is simple, inexpensive and quick. Polyethylene glycol precipitation is sufficient to obtain a purity of more than 90%. 5) Chicken antibodies are acid- and heat-resistant and might therefore be orally applied to prevent or to cure infectious intestinal diseases of young animals or humans. 6) Immunization with complete Freund's adjuvant is well tolerated and produces no inflammatory reactions and 7) collecting eggs is, in contrast to bleeding animals, non-invasive. In this review we present both, the method how to produce and to isolate yolk antibodies as well as their possible application in science, diagnosis, prophylaxis and therapy.     

Light intensity,intermittent lighting and feeding regimen during rearing as affecting egg production and egg quality

1. Four light treatments and two rearing regimens were imposed on 4 breeds of laying hen, using 6144 birds in an 8‐room climate house.

2. Room treatments were a standard lighting pattern with intensities of 0.5, 2 and 15 lux and an intermittent pattern (3 h light: 3 h dark) at 15 lux. Within room treatments were ad libitum or rationed feeding during rearing and 4 breeds: ISA Brown, Hisex Brown, Shaver Brown and Hisex White.

3. Rationing during rearing, by holding intake at its 6‐week level from 6 to 14 weeks of age, was associated with significantly higher egg production and lower egg weight, but no effect on food intake, or egg output.

4. Intermittent lighting, using a repeated 3L:3D regimen was associated with higher egg weight, but a lower rate of lay, food intake, and total egg output.

5. The absence of a consistent response to light intensity, over the range 0.75 to 12.4 lux was in contrast with earlier work, and it is possible that modern prolific hybrids are more tolerant of low intensity than were earlier stocks.

6. Despite this result it is suggested that current recommendations of 10 to 20 lux in laying houses need not be changed, because such intensities are advisable on the grounds of welfare, staff working conditions and aesthetics.     

Unimportance of yolk loss in the egg as a factor limiting egg production in the domestic hen

The injection of yolk material into the body cavity to replace that lost in the egg did not increase the rate of oviposition. During the first few weeks of this procedure a drop of 18 per cent in the rate of laying was observed.

It was concluded that the loss of material in the formation of yolk is not a limitation to subsequent ovarian activity.     

Effect of dietary energy,protein, and a versatile enzyme on hen performance,egg solids,egg composition,and egg quality of Hy-Line W-36 hens during second cycle,phase two

This study was conducted to evaluate the effect of Rovabio, dietary energy, and protein on performance, egg composition, egg solids, and egg quality of commercial Leghorns in phase 2, second cycle. A 4 × 2 × 2 factorial arrangement of treatments comprising 4 dietary energy levels (2,791, 2,857, 2,923, and 2,989 kcal of ME/kg) and 2 protein levels (15.5 and 16.1%) with and without Rovabio was used. Hy-Line W-36 hens (n = 1,920, 87 wk old) were randomly divided into 16 dietary treatments (8 replicates of 15 hens per treatment). The trial lasted 12 wk. Dietary protein significantly increased feed consumption but decreased yolk color. As dietary energy increased from 2,791 to 2,989 kcal of ME/kg, feed consumption decreased from 98.0 to 94.9 g per hen daily, and yolk color increased from 5.27 to 5.56. There was a significant interaction among dietary protein, energy, and Rovabio on egg production, BW, egg mass, feed conversion, and yolk solids. Egg weight of hens fed the diets supplemented with Rovabio was significantly greater than that of hens fed the diets without Rovabio during wk 3 and 4. However, Rovabio did not significantly influence average egg weight (87 to 98 wk of age). Rovabio supplementation significantly increased BW of hens. These results suggest Rovabio had a small but significant influence on nutrient utilization of commercial Leghorns during phase 2 of the second cycle.     

Disinfection studies with Salmonella senftenberg using egg shells as germ carriers

The present investigation was carried out to study the efficiency of 8 chemical disinfectants on Salmonella senftenberg in the presence or absence of serum (organic matter) using egg shell as bacterial carrier. The most of the tested disinfectants were effective in the used concentrations after a working time of 60 min. at room temperature. Some quaternary ammonium compounds proved to be not effective.     

Re: Faecal egg counts as a guide for drench use

Extract

Dr McKenna is correct in pointing out that the correlation quoted was between FECs and the corresponding worm burdens from individual animals. We were always aware of this, but during the reviewing/editing process a number of changes were made to the paper which unfortunately included the insertion of the word “mean” in the sentence concerned. Regrettably this change was missed during our check of the galley proofs.     

Extraneous egg shell calcification as a measure of stress in poultry

The incidence of eggs showing abnormal shell calcification amongst those produced by hens kept in individual battery cages, hens kept in battery cages in groups of 3 and hens kept in battery cages in groups of 4 was studied. There was good agreement between observers in the assessment of abnormal eggs. Hens kept in individual cages laid fewer abnormal eggs than hens kept in groups of 3 or 4. There was no significant difference in the incidence of abnormal eggs between hens kept in groups of 3 or 4. The results of this study support the idea that the incidence of eggs showing abnormal calcification may provide a quick and reliable method of measuring stress in hens which lay brown shelled eggs.     

High mortality in egg layers as a result of necrotic enteritis

A new facility was designed to hold 1.8 million birds in 10 houses; chickens were placed in five of the houses, and the remaining five houses were under construction when this outbreak occurred. An increase in mortality was reported in five houses; however, mortality in house 7 was quite high. Well-fleshed birds were suddenly found dead without a significant drop in egg production. The middle and distal intestines were distended with gas, congested, thin walled, atonic, and bluish or pale in color with sloughed mucosa in some places. Necrotic enteritis was diagnosed as the cause of increased mortality. The ingesta in the crop occasionally contained flies. The 4-wk mortality in house 7 was 6.55% with a loss of 10,898 chickens. The 4-wk mortality rate in the other houses ranged from 0.54% to 1.98%. The houses affected with necrotic enteritis were treated for coccidiosis with amprolium because low numbers of the oocysts were present in the intestinal specimens of some of the chickens. Household bleach was added to the water at a dilution of one part bleach to 1040 parts water to control bacterial contamination. The fly (Musca domestica) population was out of control. Clostridium perfringens was isolated from the alcohol-washed macerated flies caught from houses 4 and 7. Dead flies were often seen in the feed troughs. The chickens may possibly have had C. perfringens infection as a result of consumption of dead flies or their secretions/excretions. The alcohol-washed, macerated, clarified fly extract from the affected houses caused death in 11 inoculated mice and paralysis in one mouse. Similarly, illness and mortality were present in four mice inoculated with clarified intestinal contents. The bacterium isolated on anaerobic culture was identified as C. perfringens by polymerase chain reaction. The disease was brought under control after straw was added and mixed in with the litter. As a result, the litter temperature increased, causing a decrease in the fly population. This study suggests that flies in the poultry houses acted as mechanical transmitters of C. perfringens and that the development of necrotic enteritis was by ingestion of bacteria present in the flies and their secretions/excretions.     

The outer membrane of the avian egg shell as a reticular structure

The shell membranes of fowl, duck, quail and turkey eggs were examined by electron microscopy. A proportion of the outer membrane fibres from all sources were interconnected by lamellae about 90 A thick. The lamellae, which are probably protein, endow the outer membrane with a secondary reticulum reinforcing the reticulum formed by the fibres themselves.     

Seroprevalence of egg drop syndrome - 76 virus as cause of poor egg productivity of poultry in Nsukka,South East Nigeria

To determine if egg drop syndrome 76 virus infection is among the causes of lowered egg productivity in commercial poultry farms in South Eastern Part of Nigeria and to know the prevalence of the infection, ten farms with history of lowered egg production in Nsukka local government area of Enugu State were randomly selected. Sera from ten hens in each of the selected farms were assayed for antibodies against EDS 76 virus by the haemagglutination-inhibition (HI) test. The mean HI titre of the ten hens in each of the farms was recorded as EDS - 76 antibody titre for the farm. Nine out of the 10 farms tested were positive for EDS - 76 antibodies with HI titres ranging between 16 and 256. Out of 10 flocks with production of 65% and above 9 were EDS-76 HI negative.     

Evaluation of beta‐apo‐8'‐garotenal as an egg yolk pigmenter

Beta‐apo‐8'‐carotenal has been shown to be an effective egg yolk pigmenter when fed singly or in combination with dehydrated alfalfa and yellow corn. More effective pigmentation appeared to have been obtained with the lower levels of the β‐apo‐8'‐carotenal supplemented to diets containing dehydrated alfalfa and yellow corn. The compound can be used alone in a pigment‐free diet to obtain satisfactory egg yolk pigmentation.     

桑树叶粉作为饲料蛋白原料对蛋鸡生产性能和蛋品质的影响

文章旨在研究不同水平的烘干桑树叶粉对产蛋鸡生产性能和蛋品质的影响。试验选择产蛋性能一致的26周龄海兰粉壳蛋鸡900只,随机分为4组,每组5个重复,每个重复45只鸡。试验采用单因素试验设计,共含4种日粮。对照组饲喂玉米-豆粕型日粮,3个处理组分别在基础日粮中添加10%、15%和20%的桑树叶粉,试验共开展12周。结果:日粮中桑树叶粉添加水平显著影响蛋鸡的生产性能(P<0.05);随着桑树叶添加水平的升高,蛋鸡产蛋率、采食量、蛋重和平均蛋重显著降低(P<0.05)。随着桑树叶粉添加水平的升高,鸡蛋哈夫单位显著提高(P<0.05),蛋黄和蛋壳重量显著降低(P<0.05);32周龄鸡蛋蛋黄颜色L、a、b评分显著升高(P<0.05),20%桑树叶粉组蛋黄颜色L、a、b评分最高(P<0.05)。日粮添加10%~20%桑树叶粉较对照组均显著提高了38周龄鸡蛋蛋黄颜色L、a、b评分(P<0.05),其中蛋黄颜色L和a评分随桑树叶粉添加水平的升高显著升高(P<0.05)。结论:日粮桑树叶粉添加水平可以达到10%,其对蛋鸡的产蛋性能和蛋品质无负面影响。蛋鸡日粮添加桑树叶粉可以提高产蛋高峰期鸡蛋蛋黄的着色效果。