Silicon in broiler drinking water promotes bone development in broiler chickens

1. Skeletal abnormalities, bone deformities and fractures cause significant losses in broiler production during both rearing and processing. Silicon is an essential mineral for bone and connective tissue synthesis and for calcium absorption during the early stages of bone formation.

2. Performance was not affected by the addition of silicon. However, broilers receiving silicon showed a significant increase of phosphorus, zinc, copper, manganese and ash in the tibia.

3. In conclusion, broiler performance was not impaired by adding the tested silicon product to the drinking water. In addition, bone development improved, as demonstrated by higher mineral and ash content.

4. Further studies are required to determine the optimal concentration of silicon, including heat stress simulations, to better understand the effects of silicon on bone development.

     

Performance of broiler chickens given whey in the food and/or drinking water

1. The effects on food intake and weight gain of offering broiler chickens (2 to 7 weeks of age) dry food, wet food, wet food containing whey, whey as drinking liquid and combinations of two of these were studied in 5 experiments. 2. Wet feed generally improved both weight gain and feed efficiencies significantly. Feeding whey also improved weight gain and feed conversion efficiency, but whey offered as a drinking fluid had an adverse effect on broiler performance. 3. When whey was offered both as drinking liquid and added to the food it had a deleterious effect. 4. When whey was offered from 4 or 6 weeks of age, it had a better effect than when offered from 2 weeks of age. 5. There was better performance when whey in the drinking water was diluted and/or offered on alternate days or half-days. 6. Broilers allowed to choose between wet and dry feed when water was freely available chose mostly dry feed; in the absence of drinking water they chose mostly wet food. Birds offered water and liquid whey avoided whey completely. 7. It is concluded that whey can be used in diets for broiler chickens by incorporating it in the food as long as drinking water is offered ad libitum. Whey may be offered as a drink if the food is mixed with 1.8 times its weight of water but it is better to dilute the whey with an equal volume of water whether it is added to food or given as drink. Good results can also be obtained when undiluted whey is offered alternately with water, either in half-day or full-day periods.     

Immunization of broiler chickens with a commercial infectious laryngotracheitis vaccine in the drinking water.

Seventy-five thousand broiler chickens in four flocks were immunized at four weeks of age with a commercial infectious laryngotracheitis vaccine administered in the drinking water. Three of the flocks exhibited a vaccine reaction represented by mild respiratory illness between seven and 14 days after vaccination. Immunity challenge experiments demonstrated 97% protection in one trial and 67% in another trial in which the dose of challenge virus was increased fourfold. In the latter trial a parallel comparative vaccination by eye administration was 87% protective. None of the vaccinated birds died of the challenge exposure whereas all the unvaccinated control chickens became ill, several showed the acute severe form of the disease and 36% died. Similar favourable results were obtained in large-scale water immunization programs involving more than 200,000 birds. Serum antibody levels determined before immunity challenge were, within wide limits, inversely related to the severity of clinical disease which developed from the challenge inoculation.     

Control of salmonella infections in broiler chickens by the acid treatment of their feed

In three experiments a solution of formic acid (Bioadd) was added to feed 'naturally' contaminated with salmonellas. In two of them no salmonella infections were demonstrated in broiler chickens given feed containing 0.6 per cent (w/w) of the formic acid solution for seven weeks and in the third the infection rate was reduced considerably. In four other experiments the feed was contaminated artificially with between 1 and 47 Salmonella kedougou/g and a second product (BPO12), consisting of a mixture of formic acid and propionic acid, was evaluated. When it was added at 0.5 to 0.68 per cent (w/w) only one of 30 groups of 10 to 12 birds became infected with S kedougou by two weeks of age, compared with 22 of 27 control groups. The treatment of the feed with BPO12 one week before the addition of the salmonellas prevented the establishment of infection in chicks given the treated feed, indicating that acid treatment will provide protection against subsequent recontamination of the feed with the organisms. The isolation rate of S kedougou from artificially contaminated feed treated with BPO12 was reduced only slightly but the feed was apparently 'safe' for the birds which consumed it.     

Growth performance and meat quality of broiler chickens supplemented with Rhodopseudomonas palustris in drinking water

1. The effect of the bacterium, Rhodopseudomonas palustris, on the growth performance and meat quality of broiler chickens was investigated.

2. A total of 900-d-old Arbor Acres broilers were allocated to three experimental treatments for 6 weeks. Chicks were administered with R. palustris in drinking water as follows: (i) control group without R. palustris; (ii) treatment 1 (R1) with R. palustris of 8 × 10⁹ cells per chick per day in drinking water; (iii) treatment 2 (R2) with R. palustris of 1.6 × 10¹⁰ cells per chick per day in drinking water.

3. The results showed that, compared with that of control, both groups of R. palustris treatment increased daily weight gain and improved feed conversion ratio of broiler chickens significantly during the whole growing period of 6 weeks.

4. Both total and glutamic acid contents of chicken breast fillet in R. palustris treatment R2 were higher, while the fat content was lower, than those of the control group. Furthermore, R. palustris treatments also improved sensory attributes of chicken breast fillet.

5. As a probiotic providing rich nutrients and biological active substances, R. palustris administration in drinking water displayed a growth promoting effect and improved meat quality of broiler chickens.     

Anticoccidial efficacy of drinking water soluble diclazuril on experimental and field coccidiosis in broiler chickens

Prophylactic and curative capacity of water soluble formulation of Diclazuril (Diclosol 1%) and feed additive form (Clinacox, 0.5%) were tested against Eimeria infection in broiler chickens. Such testing was performed both experimentally and in the field. Toltrazuril (Baycox, 2.5%) was used as reference control drug. Water soluble formulation of Diclazuril induced a marked inhibitory effect on the different stages of the parasite life cycle in experimentally infected treated birds especially when applied on the day when blood first appeared in the faeces [fifth day post-infection (d.p.i.)] as well as on the second day of blood dropping (6 d.p.i.). Both tested dosage levels of Diclazuril water soluble formulation in drinking water (5 and 10 ppm) showed the same effect in controlling coccidial infection and reducing the total oocyst numbers, lesion and faecal scores. Moreover, there was no significant difference in the efficacy of water soluble form of Diclazuril and the reference control drug (Toltrazuril, 25 ppm). In addition, testing the water soluble formulation (5 ppm) in naturally infected poultry farm (20,000 birds), showed the same anticoccidial effect observed when using Toltrazuril, as a treatment for coccidiosis. In conclusion, addition of Diclazuril at the dose of 5 ppm in the drinking water of naturally coccidia infected bird induced the same effect as 25 ppm of Toltrazuril as a treatment for coccidiosis in chickens.     

Passive immunization to reduce Campylobacter jejuni colonization and transmission in broiler chickens

Campylobacter jejuni is the most common cause of bacterium-mediated diarrheal disease in humans worldwide. Poultry products are considered the most important source of C. jejuni infections in humans but to date no effective strategy exists to eradicate this zoonotic pathogen from poultry production. Here, the potential use of passive immunization to reduce Campylobacter colonization in broiler chicks was examined. For this purpose, laying hens were immunized with either a whole-cell lysate or the hydrophobic protein fraction of C. jejuni and their eggs were collected. In vitro tests validated the induction of specific ImmunoglobulinY (IgY) against C. jejuni in the immunized hens’ egg yolks, in particular. In seeder experiments, preventive administration of hyperimmune egg yolk significantly (P < 0.01) reduced bacterial counts of seeder animals three days after oral inoculation with approximately 10⁴ cfu C. jejuni, compared with control birds. Moreover, transmission to non-seeder birds was dramatically reduced (hydrophobic protein fraction) or even completely prevented (whole-cell lysate). Purified IgY promoted bacterial binding to chicken intestinal mucus, suggesting enhanced mucosal clearance in vivo. Western blot analysis in combination with mass spectrometry after two-dimensional gel-electrophoresis revealed immunodominant antigens of C. jejuni that are involved in a variety of cell functions, including chemotaxis and adhesion. Some of these (AtpA, EF-Tu, GroEL and CtpA) are highly conserved proteins and could be promising targets for the development of subunit vaccines.     

Oral salmonella antigens for the control of salmonella in chickens

Multivalent antigen preparations of sonicated lyophilized cells derived from up to 6 different salmonella serotypes were added in decreasing levels to broiler feed throughout the broiler's life. Several preliminary experiments challenging chicks via contaminated feed with some of the homologous serotypes showed that salmonellae were cleared more rapidly from treated chicks than from untreated controls and that fewer isolations of salmonellae were made from their ceca.     

Food availability and the feeding and drinking behaviour of broiler chickens grown commercially

1. Field observations were made on the effect of food depth in pans on the feeding and drinking behaviour of commercially grown broiler chickens aged between 17 and 43 d. 2. The group of birds receiving less food in pans had longer visits to the pans, occupied their feeding space more completely, evicted each other more often from pans and were more 'competitive' and less 'relaxed' when feeding. 3. These observations provide data about the feeding and drinking behaviour of broiler chickens reared in commercial conditions and emphasise how environmental factors, particularly food management, can influence bird behaviour. 4. The potential for qualitative and quantitative changes of feeding behaviour to affect performance is also discussed.     

Tea polyphenols reduce glucocorticoid-induced growth inhibition and oxidative stress in broiler chickens

1. The effects of dietary polyphenols (PP) on growth and oxidative stress in the corticosterone (CTC) treated broiler chickens model were studied. 2. Chicks (Cobb strain) were divided into 3 (CTC) x 3 (PP) blocks and given diets containing CTC at concentrations of 0, 10 and 20 mg/kg. 3. The body weight gain was lower when the birds were treated with CTC. However, the high dose of PP tended to reduce the effect of CTC. 4. The abdominal fat content, plasma triglyceride concentration and liver weight were increased by CTC and reduced by PP. 5. Muscle and liver thiobarbituric acid reactive substance (TBARS) were elevated by CTC and these effects were reduced by PP. Plasma CTC concentration was increased by dietary CTC treatment and decreased by PP. 6. In conclusion, our results indicate that PP can minimise growth inhibition, hyperlipidemia and oxidative stress induced by CTC treatment in broiler chickens.     

The influence of dietary protein and antimicrobial feed additives on salmonella carriage by broiler chickens

Salmonella carriage in broiler chickens was not apparently influenced by the protein concentration of the ration, pelleting or by the coccidiostat monensin. The inclusion of penicillin in the diet was associated with an increase in salmonella shedding, particularly in the first half of the rearing period, but did not influence the lactobacillary count in the crop or the pH of the contents of the crop, gizzard and caecum. Furazolidone medication (150 mg/kg food) for the first 10 days had no effect on salmonella carriage at the time of slaughter (seven weeks) and studies into the influence of growth promoting antibiotics (avoparcin, bacitracin and virginiamycin) on salmonella shedding were inconclusive. Circumstantial evidence indicated that the food was the most probable source of infection for the birds studied in these experiments.     

Ocular responses to ammonia in broiler chickens

In two trials, 60 male commercial broilers were placed in each of eight environmentally controlled chambers receiving 0, 25, 50, or 75 ppm aerial ammonia from 1 to 28 days. Birds exposed to 25 ppm (lower concentration) ammonia gas developed ocular abnormalities but at a slower rate when compared with birds exposed to 50 and 75 ppm (higher concentrations). Birds exposed to higher concentrations also developed more severe lesions. With little atmospheric ammonia present after 28 days of the grow-out stage, the corneas indicated signs of healing. Lymphocytes and heterophils were seen in the iris at 49 days in ammonia-exposed birds even when ammonia exposure was terminated at 28 days. The lower ammonia concentrations resulted in abnormalities that were slight when compared with those seen at the higher ammonia concentrations. As measured by the incidence of inflammatory infiltrates in the trachea, lung, and air sacs, respiratory tract tissues did not appear to be affected by any tested level of aerial ammonia. The findings in this investigation represent the first report indicating that ammonia-induced uveitis in chickens clears rapidly after exposure to ammonia ceases.     

Effect of chlorination of drinking water on experimental salmonella infection in poultry

The type of drinker used for poults influenced the level of free available chlorine (FAC) in chlorinated water as well as the total plate count, fecal coliform count, and number of salmonellae in chlorinated and non-chlorinated drinking water. Nipple drinkers maintained higher levels of FAC in drinking water than Swish-cups, Swish-cups maintained higher levels than MarkIII, and MarkIII maintained higher levels than trough drinkers. The level of FAC retained in the water in trough drinkers was insufficient to exert a bactericidal effect against coliforms and salmonellae. Chlorination of drinking water and the resulting diminished number or absence of salmonellae in the drinking water did not lower the number of salmonellae per gram of cecal contents in challenged or unchallenged but exposed poults. The number of salmonellae per gram of cecal contents decreased significantly (P less than 0.01) in poults between 14 and 21 days of age, irrespective of whether or not the poults drank chlorinated water.     

Supplementation of broiler drinking water with liquid ammonium polyphosphate

1. In each of two experiments lasting 21 days a commercially available ammonium polyphosphate solution was provided in the drinking water as the sole source of supplemental phosphorus for day-old chicks housed in batteries. 2. In both experiments, similar daily phosphorus intakes either from dicalcium phosphate in the food or from ammonium polyphosphate in the drinking water supported equivalent responses in body weight gains. The same was true for the tibia ash results in experiment 2. 3. Liquid ammonium polyphosphate, while marketed for addition to diets, appears to be also very effective as a waterborne source of phosphorus for broilers.     

Large-scale trials to study competitive exclusion of salmonella in chickens

Competitive exclusion of salmonella by native gut microflora was studied in 24 groups of 100 chickens each started in thoroughly cleaned and sanitized isolation facilities. During 53-day test periods, infection by both Salmonella infantis and S. typhimurium was greatly restricted in groups previously treated with native microflora compared with control groups. Feed and water starvation for 48 hours starting at either 23 or 51 days did not affect the incidence of infection in protected groups. The protective flora spread readily to adjacent untreated groups; infected groups given the protective flora at 11 days exhibited a more rapid elimination of infection than untreated control groups.     

减轻肉鸡热应激的措施

夏季天气炎热,严重影响肉鸡的生产.鸡群受热应激的影响,采食量减少,生长缓慢,因此,在夏季必须注意鸡舍的防暑降温,加强饲养管理,调整营养,应用药物防制等,以减少热应激造成的损失.     

保证饮水质量的各种主要因素

水是家禽生活中唯一最重要的营养来源。鸡只在没有任何其它营养来源的情况下,只要有水就可以存活较长时间。虽然鸡只需要提供充足饮水的重要性已被广大同仁所接受,然而饮水质量对生产性能方面影响的重要性却往往被大家所忽视。 饮水质量可以直接或间接影响鸡群的生产性能。饮水中矿物质、细菌或有毒成份的含量较高会严重影响鸡只体内正常的生理过程,从而引发内脏功能紊乱。矿物质含量高也会阻塞饮水系统,使鸡只无法得到饮水。而且还会导致饮水器漏水、使垫料潮湿,从而引发疾病和腿病问题。 饮水质量由几项标准所确定。然而,由于许多标准都是从其它家畜或人类的饮水标准发展而来,所以很难确定家禽高质量的饮水标准该是如何。 另外,很多指标不是依据鸡只的生产性能表现,而是根据其死亡率的结果而制定。各种矿物质之间的相互作用,以及实际消耗的饮水量也很难制定任何某种矿物质确实可接受的毒性水平。 用水样进行化验分析是饮水管理中最基本的组成部分。然而化验分析的结果必须准确无误,以便确定最佳处理方法或确定采取措施的依据。 下列为影响饮水质量最主要的因素: