Effect of feeding clinoptilolite (zeolite) on the performance of three strains of laying hens

1. One hundred and twenty 16‐week‐old single combed pullets of three strains were fed on a diet containing 135 g protein/kg with or without 50 g clinoptilolite/kg in a trial with 20 hens per treatment. Sterile river sand replaced clinoptilolite in the control diet in order to keep the diets isoenergetic. The hens were individually caged in a naturally ventilated laying house and fed one of the two diets for ten 28‐d periods.

2. Significant dietary effects of feeding clinoptilolite were observed with number of eggs laid per hen, shell thickness, efficiency of food utilisation and droppings moisture content. No significant dietary effects between treatments were observed with body weight, age at first egg, egg weight, Haugh units, food intake/hen and rate of amino acid absorption of radioactive lysine and methionine into the bloodstream. Significant differences between strains were observed with regard to all parameters except food intake/hen. There were no significant strain × clinoptilolite interactions.     

The effect of feeding zeolite (clinoptilolite) on the health status of sheep

Under the experimental conditions of a clinic, zeolite from the N. Hrabovec locality was studied as to its effect on the health condition of sheep. Zeolite was added to the feed mixture at a rate of 0.15 g per 1 kg of live weight daily for three months. The trials were performed with five sheep of the Merino breed. Five sheep were used as controls. No differences were found in the health condition and general behaviour of sheep fed zeolite and sheep of the control group. Neither were substantial differences observed in the indices of the other parameters under study--actual and total acidity, content of volatile fatty acids in rumen contents, blood picture, content of macroelements and microelements, nor in the transaminase activity of blood serum and acid-base homeostasis in blood. Before the zeolite supplementation of feed ration is introduced in practice, detailed studies should be conducted and the optimum zeolite dose should be determined.     

The effect of feeding hemp seed meal to laying hens

Seed of the hemp cultivar Unika-b was cold-pressed to obtain hemp seed meal (HSM) containing 307 g/kg crude protein and 164 g/kg ether extract (60 g/kg linoleic acid, 120 g/kg alpha-linolenic acid, 160 g/kg oleic acid, lesser amounts of palmitic, stearic, and gamma-linolenic acids). For 4 weeks, 102 43-week-old DeKalb Sigma hens were fed on isonitrogenous and isoenergetic diets containing 0, 50, 100 or 200 g/kg HSM. Eggs were collected for fatty acid analysis during the fourth week of feeding these diets. No significant differences were found between feed treatments for egg production, feed consumption, feed efficiency, body weight change or egg quality. Increasing dietary inclusion of HSM produced eggs with lower concentrations of palmitic acid and higher concentrations of linoleic and alpha-linolenic acids.     

Zinc‐bearing zeolite clinoptilolite improves tissue zinc accumulation in laying hens by enhancing zinc transporter gene mRNA abundance

A study was conducted to investigate effects of zinc‐bearing zeolite clinoptilolite (ZnCP), as an alternative for zinc sulfate (ZnSO₄), on laying performance, tissue Zn accumulation and Zn transporter genes expression in laying hens. Hy‐Line Brown laying hens were allocated to three treatments, each of which had six replicates with 15 hens per replicate, receiving basal diet supplemented with ZnSO₄ (control, 80 mg Zn/kg diet), 0.23% ZnCP (40.25 mg Zn/kg diet) and 0.46% ZnCP (80.50 mg Zn/kg diet) for 8 weeks, respectively. Compared with control, hens fed diet containing 0.23% ZnCP had similar Zn content in measured tissues (P > 0.05). A higher ZnCP inclusion (0.46%) enhanced Zn accumulation in liver (P < 0.05) and pancreas (P < 0.05). In addition, ZnCP inclusion increased blood iron (Fe) content (P < 0.05). ZnCP supplementation enhanced jejunal metallothionein‐4 (MT‐4) messenger RNA (mRNA) abundance (P < 0.05). ZnCP inclusion at a higher level (0.46%) increased mRNA expression of MT‐4 in pancreas (P < 0.05) and zinc transporter‐1 (ZnT‐1) in jejunum (P < 0.05). The highest ZnT‐2 mRNA abundance in jejunum was found in hens fed 0.23% ZnCP inclusion diet (P < 0.05). The results indicated that ZnCP reached a higher bioavailability as compared with ZnSO₄ as evidenced by enhanced tissue Zn accumulation and Zn transporter genes expression.     

The intermittent feeding of anti-bacterial and-or antifungal agents to laying hens

A study was conducted in order to ascertain the effects of feeding large doses of various antibacterial (chlortetracycline, furazolidone, bacitracin) and/or anti‐fungal (nystatin, cupric sulphate) agents to laying hens on an intermittent basis. None of the drugs tested enhanced the performance of the birds when fed singly. However, birds that received a diet intermittently containing a broad‐spectrum antibiotic (110 mg/kg of diet) exhibited a performance superior to that of the control group when the antibacterial treatment was immediately followed by the feeding of a ration containing 55 mg nystatin/kg, during the 7 subsequent days.

It is possible that the intermittent, successive feeding of massive amounts of antibacterial and antifungal agents may act synergistically to promote egg production and efficiency of food utilisation. An economic evaluation of the data revealed that, at constant egg production levels, the feeding of chlortetracycline‐supplemented diet (110 mg/kg of diet) for 3 consecutive days, immediately followed by feeding a nystatin supplement (55 mg/kg of diet) for 7 consecutive days, the cycle being repeated every 4 weeks, led to a larger net profit than the feeding of chlortetracycline‐supplemented or unsupplemented diets.     

饲养方式及日粮对固始鸡蛋胆固醇含量的影响

试验选用630只12周龄的固始蛋用母鸡,按平均体质量分成7组,每组3个重复。第1～6组放养,分别饲喂6种不同配方的日粮;第7组笼养,饲喂日粮与第1组试鸡相同。结果表明,第1和第7组每克蛋黄胆固醇含量及每枚鸡蛋胆固醇含量差异不显著,说明饲养方式对降低鸡蛋胆固醇含量无明显效果,但放养表现出一定的优势,放养鸡蛋黄比例比笼养鸡低,放养鸡每枚鸡蛋胆固醇含量比笼养鸡低7.35%;对放养鸡而言,当日粮中蛋白质水平为13.77%时,每克蛋黄胆固醇含量随日粮中代谢能水平的提高而上升,提高日粮中蛋白质水平将显著提高蛋黄中胆固醇浓度。     

大葱叶粉饲喂产蛋鸡的应用研究

大葱芳香、辛温。是人们日常生活中广泛食用的蔬菜及调味品．但人们主要食用葱的茎和少量叶。大部分葱叶被弃掉．尤其是在入冬前冬葱贮藏时，废弃的大葱叶数量是相当可观的。而且大葱叶富含生物活性物质和多种维生素．饲料中添加一定量的大葱叶，可以改善饲料的适口性．增加畜禽的采食量．促进消化吸收，加速畜禽生长．还可以起到消炎、杀菌、驱虫等防病保健作用。为此．我们课题组将大葱叶添加于产蛋鸡生产中进行研究．取得了初步可喜的成果。具有研究和开发价值。现将大蒜叶加工后的大蒜叶粉饲喂产蛋鸡的试验研究报告如下：     

Restricted feeding time and the behaviour of caged laying hens

1. Layers housed as pairs in cages were denied access to food from 07.30 to 15.30 h each day. Analyses of video records of daily activity patterns showed several behaviour changes compared with the patterns shown by similar birds allowed ad libitum (AL) access to food. 2. Birds given restricted access (RA) to food spent more time sitting and cage pecking while unable to feed than those feeding ad libitum during the same period. They also engaged in less agonistic pecking and the lengths of bouts of drinking were reduced during the period of food denial compared with the AL treatment. 3. After the food troughs were uncovered birds on the RA treatment showed fewer bouts of feather pecking but more bouts of drinking than the AL treatment. 4. Improvements previously reported in the efficiency of food utilisation of birds on the RA treatment may have been the result of additional sitting, although other activities requiring energy expenditure were performed. 5. It is concluded that restricting access to food on a time basis has both positive and negative effects on the welfare of caged layers.     

养好产蛋鸡的措施

<正>一、把好13关1.通风关。如夏季天气炎热且降雨较多使鸡舍内潮湿闷热、异味较强,进而为多种病原体及昆虫提供了较好的滋生和繁殖条件,所以夏季应通过搞好通风工作,将鸡舍内的不良气体和多余的水分排出。2.降温关。蛋鸡最佳产蛋温度为18～25℃,最高不超过28℃,超过30℃时产蛋率就会明显下降甚至中暑,所以应通过遮阳减少辐射和通风加快蒸发、制冷,降低鸡舍内温度,有条件的必要时用空调降温。     

Stability of fear and sociality in two strains of laying hens

1. This trial studied the effects of strain and age on tonic immobility (TI) duration, emergence time (ET) and social reinstatement time (SRT) in laying hens and investigated the consistency of individual behavioural characteristics over rearing and laying periods and the correlations between these behavioural traits. 2. One hundred chicks from each of ISA Brown (ISA) and Lohmann Tradition (LT) laying hens were reared from one day old in pens. At 3 weeks, birds of each line were divided into 4 groups. Twenty birds in one group of each line were marked individually for repeated testing and the other groups were assigned for single testing to test the habituation effect and possible age effects at a group level. 3. ISA birds had higher overall means for TI duration and latency to leave the start box. ISA also showed longer latency in SRT at week 28 than Lohmanns. TI duration increased from weeks 3 to 10 and then decreased to week 35 in both lines. The latency to explore the test area and to reinstate decreased from weeks 10 to 35. 4. Tonic immobility, exploratory and social reinstatement behaviours were consistent over time in both lines, as revealed by Kendall's W coefficient of concordance. 5. In social test situations, an inter-situational consistency was found, that is, birds emerged quickly from the start box and reinstated quickly with their companion. TI (non-social test) was negatively correlated with ET and SRT. Thus the two lines of laying hens respond differently in social and non-social tests.     

合生素对蛋鸡生产性能的影响

选择49周龄海兰褐蛋鸡1275只,随机分成5组,设3个正对照组、1个负对照组和1个试验组。试验组饲喂负对照组日粮（未加微生态制剂）基础中添加0．05％合生素,3个正对照组分别饲喂负对照组日粮基础中依次添加其他微生态产品M100、NW和GEK（营养标准相对负对照组低6％蛋白）的日粮。预试期30d,试验期30d,考察不同添加剂产品对蛋鸡生产性能的影响。结果表明,合生素添加组与M100添加组、负对照组、NW添加组和GEK添加组的生产性能相比．产蛋率分别提高4．82％、1．01％、1．78％和5．55％;蛋质量分别提高2．79％、3．77％、2．61％和3．82％。统计上均差异显著。合生素添加组和正负对照组的料蛋比分别是2．331、2．471、2．369、2、400和2．441。鸡蛋的平均合格率统计上均无显著差异。这表明,饲料中添加0．05％合生素可达到较理想的效果。     

Physicochemical determinants of pH in pectoralis major of three strains of laying hens housed in conventional and furnished cages

1. Post-mortem decline in muscle pH has traditionally been attributed to glycogenolysis-induced lactate accumulation. However, muscle pH ([H⁺]) is controlled by complex physicochemical relationships encapsulated in the Stewart model of acid–base chemistry and is determined by three system-independent variables – strong ion difference ([SID]), total concentration of weak acids ([A_tot]) and partial pressure of CO₂ (PCO₂).

2. This study investigated these system-independent variables in post-mortem pectoralis major muscles of Shaver White, Lohmann Lite and Lohmann Brown laying hens housed in conventional cages (CC) or furnished cages (FC) and evaluated the model by comparing calculated [H⁺] with previously measured [H⁺] values.

3. The model accounted for 99.7% of the variation in muscle [H⁺]. Differences in [SID] accounted for most or all of the variations in [H⁺] between strains. Greater PCO₂ in FC was counteracted by greater sequestration of strong base cations. The results demonstrate the accuracy and utility of the Stewart model for investigating determinants of meat [H⁺].

4. The housing differences identified in this study suggested that hens housed in FC have improved muscle function and overall health due to the increased opportunity for movement. These findings support past studies showing improved animal welfare for hens housed in FC compared to CC. Therefore, the Stewart model has been identified as an accurate method to assess changes in the muscle at a cellular level that affect meat quality that also detect differences in the welfare status of the research subjects.     

The efficacy of three commercial Mycoplasma gallisepticum vaccines in laying hens

The efficacy of three commercial Mycoplasma gallisepticum (MG) immunizing agents-a bacterin, a recombinant fowlpox-MG vaccine, and a live F-strain vaccine-was compared in specific-pathogen-free hens in egg production. Three groups of 25 chickens were vaccinated with one of the vaccines at 10 wk of age and 25 birds were not vaccinated. At 25 wk of age (and approximately 50% egg production), 20 birds from each of the three vaccinated groups and 15 nonvaccinated controls were challenged with virulent R-strain via aerosol; the birds were necropsied and evaluated at 10 days post-challenge. The MG bacterin and live F-strain vaccinations were both protective and resulted in significant differences in air sac lesions, tracheal lesions, and ovarian regression compared to the nonvaccinated controls and the recombinant fowlpox-MG vaccine (P < or = 0.05). The evaluation of ovarian regression is a useful method of testing the efficacy of MG vaccines in laying hens.     

Aversiveness of mechanical conveying to laying hens

1. Passive avoidance was used to investigate the aversive‐ness to laying hens of the sound and motion associated with travel on a short section of flat‐belt conveyor.

2. Three groups of 7 birds were trained to key‐peck for food at an operant panel and then exposed to a passive avoidance schedule in which the treatment stimuli were activated by key‐pecking.

3. Birds exposed to both sound and motion (SM), or sound only (S) showed significantly greater suppression in key‐pecking than birds in the control group (C) which had not been exposed to either stimulus. No significant difference was found in aversion levels between the S and the SM groups.

4. Sound alone appeared to be as aversive as sound and motion combined, although certain caveats to this conclusion are given.     

Sorption characteristics of natural zeolite (clinoptilolite) in biological material in vitro

The zeolite (clinoptilolite) sorption of arsenic, cadmium, and lead ions from rumen fluid and abomasum juice was investigated in laboratory conditions. Zeolite was found to sorb 91% of lead and 45% of cadmium from rumen fluid in 24 hours. The sorption effectiveness was even higher from abomasum juice where zeolite sorbed 98% lead in 24 hours.     

甪里艾叶粉对蛋鸡产蛋性能与蛋品质的影响

为了研究甪里艾叶粉对蛋鸡产蛋性能与蛋品质的影响,试验选用50周龄健康状况良好、生产性能相近的海兰褐蛋鸡288只,随机分为四组,一个对照组,三个试验组,各组甪里艾叶粉分别添加0、1%、2%、3%,每组6个重复,每个重复12只鸡,预试期为7 d,试验时间为42 d。结果显示:(1)甪里艾叶粉对产蛋性能的影响:试验各组的平均日产蛋重均高于对照组(P0.05),分别提高了2.62%、3.58%、2.41%;随着艾叶粉添加量的增加,平均日采食量显著减少(P0.05),分别减少了2.76%、3.29%、3.62%;试验各组料重比均显著低于对照组(P0.05),分别降低了5.10%、6.63%、5.61%;随着甪里艾叶粉添加量的增加,产蛋率分别提高了2.85%(P0.05)、3.99%(P0.01)、5.93%(P0.01)。试验各组的蛋重与对照组均无显著差异(P0.05)。(2)甪里艾叶粉对蛋品质的影响:甪里艾叶粉可显著提高蛋的比重(P0.05),其中添加量为2%时差异极显著(P0.01)。各组间的蛋形指数、哈氏单位、蛋黄颜色差异均不显著(P0.05)。但试验各组的蛋白高度分别提高了8.92%(P0.05)、11.29%(P0.05)、10.21%(P0.05),哈氏单位则相应提高了4.51%、5.67%、5.69%。各组间的蛋壳指标差异不显著(P0.05)。试验各组的蛋白比率、蛋黄比率差异不显著(P0.05),随着甪里艾叶粉添加量的增加,蛋壳比率逐渐降低,其中添加2%和3%的甪里艾叶粉可显著降低蛋壳比率(P0.05)。甪里艾叶粉可以改善海兰褐蛋鸡的产蛋性能,蛋的比重和蛋白高度显著提高,蛋壳比率呈降低的趋势。     

Effect on shell strength of feeding supplemental sources of calcium to adult laying hens given insoluble grit during the rearing period

1. An experiment was conducted to determine the separate and combined effects of giving insoluble grit during the rearing period and small or large particle size (0.3 mm and 3 to 8 mm in diameter) limestone or oyster shell, as extra sources of calcium, during the laying period. 2. For the entire laying period the extra sources of calcium resulted in improved shell strength but, overall, grit-supplements during the rearing period did not affect either egg shell strength or other performance traits. 3. An analysis for interactions however revealed that limestone of larger particle size coupled with rearing period-grit resulted in improved egg-shell strength during the last quarter of the laying period.     

Determination of gastrointestinal passage rate using three different markers in laying hens

The titanium dioxide (TiO₂) marker technique is currently widely practiced as a method to evaluate gastrointestinal (GI) passage rate in poultry. However, this method requires sacrificing the animal to obtain digesta samples, is labour‐intensive and eliminates the possibility of follow‐up studies with the same individual. The aim of this study was to evaluate whether the radiographic methods barium‐impregnated polyethylene spheres (BIPS) and barium sulphate (BaSO₄) suspension are in agreement with the TiO₂ technique and can be used as an alternative method for GI passage rate determination in laying hens. Whole‐body radiographs were taken at different time points. Hens of group 3 (n = 55) were orally inoculated with 5 g of feed mixed with 0.15 g TiO₂, 5 hens per time point sacrificed, and whole gastrointestinal organs (crop, proventriculus, gizzard, small intestine and large intestine) were collected and analysed for TiO₂ content. The average marker passage rate of hens administered BaSO₄ was significantly faster than those administered BIPS (gizzard: 15.2 hr vs. 43.2 hr; small intestine: 15.2 hr vs. 38.4 hr, respectively). A greater percentage of BIPS remained in the crop at 0, 0.5, 2, 3 and 8 hr post‐inoculation (p.i.) and in the gizzard at 2, 24, 36 and 48 hr p.i. (all p < 0.05) compared to TiO₂. In conclusion, the evaluation of the GI transit time is feasible using BIPS, TiO₂ and BaSO₄. The evaluation of the GI transit time using BIPS and BaSO₄ needs further investigation.     

The laying performance of two strains of hens offered diets containing dried poultry manure during the laying stage

1. Light‐weight (Babcock B300) and medium‐weight (Warren‐SSL) hens were offered diets, containing 0, 100 or 200 g dried poultry manure (DPM) and 11.49, 11.12 or 10.83 MJ metabolisable energy/kg respectively, between 18 and 70 weeks of age. The true protein, metabolisable energy, calcium and phosphorus contents of the DPM, from caged layer hens, were used in the diet formulation.

2. The hen‐housed laying performance of hens offered the DPM‐containing diets was significantly better for number of eggs laid and total egg mass produced but the performance of the control groups was lower than would normally be expected of those stocks. The reason for the lower rate of lay and higher mortality of hens fed on the control diet was not identified. The amount of food consumed increased as the energy content of the diet decreased and the efficiency of food conversion (EFC) of the lightweight strain was reduced; there was no significant effect on the EFC of the medium‐weight hens.

3. The inclusion of DPM in the diets had no effect on albumen quality or on the incidence of hair‐cracked, cracked or broken eggs. However, with both strains of hens, shell weight and shell thickness were poorer when 100 or 200 g DPM/kg diets were fed.