Effect of age and body weight of Greater Rhea (Rhea americana) females on egg number, size and composition

1. A study was conducted to evaluate how body weight and age of each female are related to the number and physical and chemical characteristics of the eggs produced throughout a breeding season in a captive-bred population of Greater Rheas (Rhea americana). 2. Reproductive performance of 15 females of three age classes (5 individuals per class) was monitored; female body weight was recorded before laying-onset. All the eggs laid were collected and identified, and different morphometric variables, percentage of components and fatty acid composition were determined. 3. The earlier the female started egg-laying, the longer the laying period and the greater the overall number of eggs produced. The onset of egg-laying in turn seemed to be related to the attainment of a high body weight. 4. Except for length, the values of the morphometric variables of the egg and unsaturated fatty acids (palmitoleic, oleic and linoleic) increased with female age. 5. High body weight was associated with low palmitic and palmitoleic fatty acids and high linoleic, linolenic and total unsaturated fatty acids. 6. Live weight and age of females can determine several physical and chemical characteristics of eggs.     

Physical characteristics and chemical composition of Greater Rhea (Rhea americana) eggs from wild and captive populations.

1. Eggs from wild and captive populations of Greater Rhea (Rhea americana) were studied to determine their physical and chemical characteristics. 2. Significant differences were found among populations in almost all chemical parameters studied, whereas within physical parameters only shell weight (as a proportion of the entire egg) and density showed differences. 3. Eggs from wild populations had the highest protein and linolenic acid and the lowest total lipid contents, while cholesterol levels of these eggs and of those from the largest captive area were the lowest.     

Effects of storage time on hatchability of artificially incubated Greater Rhea (Rhea americana) eggs

(1) A study was conducted to determine the effects of the length of the storage period on the hatchability of artificially incubated Greater Rhea eggs. Hatchability was evaluated in eggs gathered daily from a captive population and in eggs collected less frequently from a semi-captive population. (2) Eggs form both sites were either immediately incubated after being collected or were stored for 1 to 9 d prior to incubation. (3) The maximum number of days for which an egg could be stored without depressing hatchability (with respect to non-stored eggs) was longer in the eggs collected daily. (4) Eggs collected daily and stored for 4d or more showed total hatchability (28%) and fertile hatchability (43%) which was approximately 30% lower than non-stored eggs or eggs stored for 3 d or less. In the semi-captive population, the total and fertile hatchability of non-stored eggs and of eggs stored for one day were 40% greater than of eggs stored for 2 to 9 d (20 and 34%, respectively). (5) The period for which Greater Rhea eggs could be stored without depressing hatchability varied depending on the frequency of egg collection: non-daily egg collection reduces the possible period of storage.     

Observations on helminth infections of free-living and captive rheas (Rhea americana) in Brazil

The present work describes helminth infection of eight free-living and 12 captive rheas (Rhea americana) from, respectively, Pantanal of Mato Grosso do Sul State, and Jaboticabal, Sao Paulo State, Brazil. Captive birds were young and had a high mortality rate, while free-living birds were adult and apparently healthy. Infections were evaluated by post-mortem examination of internal organs and recovery of helminths using standard parasitological procedures. Seven species of nematodes (Sicarius uncinipenis, Torquatoides crotophaga, Deletrocephalus dimidiatus, D. cesarpintoi, Paradeletrocephalus minor, Capillaria venteli and Dicheilonema rheae) and two species of cestodes (Houttuynia struthionis and Chapmania tauricolis) were identified. P. minor, which inhabits the large intestine, was the most common helminth in free-living birds (63.9%). In captive rheas, a mean parasitic load of 173 helminths per host was found. The gizzard of these birds was the most parasitized organ and S. uncinipenis was most common (92.5%). Parasitism of free-living and captive birds and associated pathology are discussed.     

Milk fat depression and the influence of diet on milk composition

Milk composition depends on inheritance, stage of lactation, age, infection, and diet. Fat is the most variable component of milk, and its concentration depends on the supply of acetate, butyrate, and performed fatty acids to the mammary gland. This supply depends on diet and competition among organs. Adequate, effective fiber is the critical dietary consideration.     

日粮中添加富碘酵母对蛋鸡性能、蛋品质和蛋中碘含量的影响

该研究旨在评价日粮中添加富碘酵母对蛋鸡性能、蛋品质和蛋中碘含量的影响.该试验为完全随机设计.60只25周龄蛋鸡分成3组(4个重复),饲喂期为12周.日粮中添加碘的含量和形式分别如下:对照组(C),每千克日粮含1mg碘,Ca(IO3)2·H2O;试验1组(E1)和试验2组(E2)日粮中碘的含量分别为1mg/kg和2mg/kg,含碘酵母.含碘酵母对蛋鸡的增重影响不显著.经统计分析,E1组和E2组的日产蛋率不低于C组.E1组的采食量最低,E2组的饲料转化率最高.此外,E2组的蛋重和蛋白重最大(P＜0.05).E1组和E2组蛋黄中碘的含量分别比C组高80％和90％.E2组蛋壳中碘的含量约是C组的3倍.该结果说明,蛋鸡日粮中添加含碘酵母是增加鸡蛋中碘含量的有效方式.因此,通过消费富碘鸡蛋有助于消除人类缺碘症.     

Aspects of the Macroscopic Testicular and Epididymal Morphology in the Greater Rhea,Rhea Americana (Linneaus – 1758) Birds

The purpose of this research was to study the macroscopic testicular and epididymal morphology of the greater rhea. The testicles of 54 greater rhea bred in captivity were utilized. The samples were collected November 2005 (n = 14), December 2006 (n = 20) and May 2007 (n = 20). During commercial slaughter, the testicles and epididymides were collected and their following morphometric parameters were immediately measured: length, width, thickness, circumference, volume, weight of the parenchyma and the tunica albuginea, also aspects such as shape, cavity implantation, relationship with other organs and vascularization. The testicles presented cylindrical shape, with a thin, dense and transparent tunica albuginea, and the vascularization was accomplished by the testicular artery that ramifies from the cranial rectal artery. In the samples from December 2006 and May 2007, the media from the macroscopic measures of the right testicles were volume 58.7 and 14.7 ml, length 9.87 and 3.5 cm, width 2.4 and 0.6 cm, thickness 2.4 and 0.5 cm, circumference 8.0 and 2.3 cm, parenchyma weight 27.6 and 6.1 g and tunica albuginea weight 1.0 and 0.3 g, P < 0.05, respectively. The epididymides, the media from macroscopic measures December 2006 and May 2007 were volume 7.7 and 3.0 ml, length 5.8 and 1.3 cm, width 0.7 and 0.3 cm, thickness 0.6 and 0.3 cm, circumference 2.5 and 1.2 cm, tissue weight 6.4 and 2.8 g and capsule weight 0.4 and 0.1 g, P < 0.05, respectively. Some measures from the right testicle and epididymis were superior to measures taken from the left ones (P < 0.05), but these were not characterizing asymmetry. The morphometric parameters observed during November 2005 remained on an intermediate situation (P < 0.05); however, they were quantitatively closer to the means of December 2006, which may characterize it as a potential transition period between repose and sexual activity. Morphologically, the testicles and epididymides of greater rhea have common points with other researched birds; however, differences were observed. The testicles and epididymides of the Rhea americana are influenced by the environment, presenting reproductive activity season (November–December) during late spring, early summer and sexual repose season (May) during autumn–winter. The morphometric testicular and epididymal measurements were introduced. The morphometric parameters of testicles and epididymides exhibited differences between winter and spring–summer that could be established like sexual activity season.     

Coefficients for the estimation of fresh weight and volume of Greater Rhea eggs

1. Specific values of constants needed to estimate fresh weight (Kw) and volume (Kv) of Greater Rhea eggs were obtained. 2. The average value for the weight coefficient (Kw) was 0.57, whereas that for volume (Kv) was 0.51. Accuracy of results obtained with these values was +/-2.1% and +/-3.5%, respectively. 3. The fresh weight and volume of Greater Rhea eggs can be easily estimated by means of these specific coefficients when those measurements cannot be taken directly.     

The effect of diet and copper supplementation on chick growth

Two experiments are described in which various diets were fed to broiler chicks, with or without a supplement of 0.1 per cent CuSO 4.5 H₂O supplying 250 mg/kg added Cu. When the basal diet was composed mainly of wheat and fish meal with added tallow, growth responses to copper measured at 6 weeks of age were 7.6 per cent in the first experiment (highly significant) and 2.8 per cent in the second experiment (0.1 > P > 0.05). When the basal diet was composed mainly of maize and soya‐bean meal there was no response to added copper in the first experiment and a significant depression in growth in the second experiment. A basal diet containing 25 per cent of dried whey gave very poor growth (about 60 per cent of normal) but showed a large response to the addition of Cu. Responses to added Cu in all diets were generally larger in the faster growing males than in the female chicks.

Where positive growth responses to copper were obtained, food consumption was usually higher, but efficiency of food utilisation was better in the chicks given the copper‐supplemented diets.

The average concentrations of Cu found in the livers of birds with or without copper supplements were 4.41 and 4.10 mg/kg of fresh liver respectively in the first experiment and 6.88 and 4.56 mg/kg of fresh liver in the second experiment. The difference in the second experiment was highly significant.     

Hindlimb bone maturation during postnatal life in the Greater Rhea (Rhea americana,Aves, Palaeognathae): Implications for palaeobiological and zooarchaeological interpretations

The objective of this study was to study the morphological pattern of bone maturation of the hindlimb bones of Rhea americana and find out how it can affect bone morphology after a taphonomic process. Juvenile specimens (n = 10) ranging from one month old to eight months old were studied. For comparison, bones from adults and juveniles from museum specimens (n = 4 and n = 6, respectively) were studied. In fresh bones, ossification centres were identified in the proximal and distal epiphyses of the tibiotarsi and in the proximal epiphysis of the tarsometatarsi, whereas the distal region of the femora and tarsometatarsi showed abundance of cartilage. The development and extension of the ossification centres of the tibiotarsi were different. In the proximal epiphysis, the centre presented less development with respect to the distal epiphysis. In the dry tibiotarsi, the proximal centre was absent and the distal one was well preserved. Both the fresh and dry juvenile tarsometatarsi presented unfused metatarsals and bulkier and wider aspect than the adult ones. The dry femora presented a noticeable excavation between condyles, whereas the dry tarsometatarsi showed the absence of the proximal epiphysis. The femora, tibiotarsi and tarsometatarsi possessed different traits of immaturity, which differentially affect the morphology of the preserved bones during a taphonomic process.     

The effects of a protein deficiency on egg composition

Eggs were collected from groups of pullets receiving 9, 14 or 20 per cent dietary protein and the component parts were separated and weighed. The reduction in egg weight associated with protein deficiency was found to be due to reductions in all components, but yolk and shell weight changed proportionately less than total weight and albumen weight proportionately more. The resulting increase in percentage yolk was found to be of similar magnitude to that expected from a consideration of the relationship between egg size and yolk size in birds receiving adequate protein. In a similar way the increased proportion of shell apparently reflected only the relationship between egg size and surface area in eggs collected when the birds were 52 weeks of age but at 67 weeks a real increase in shell thickness on the deficient diet was also indicated.     

鸡产蛋量下降的病理简析与防治措施

鸡产蛋量下降的原因很多,有疾病性的,也有非疾病性的。疾病方面通常有流行性感冒、新城疫、传染性支气管炎、产蛋下降综合征等。但不管是什么病因引起的产蛋量下降,其途径大多又都是首先通过降低呼吸系统或消化系统功能来影响生殖系统功能的。呼吸系统器官被疾病感染,即是鼻腔、气管、支气管、肺、气囊发生炎症,对于机体需要的正常量氧气和机体急待排出的废气CO2,无疑将程度不同地受到影响。新鲜氧气供应不足,将使心脏功能程度不同的地受到削弱,并引起衰弱,从而影响血液循环正常运送营养物质,并影响肝脏对营养物质的常量储存和正常合成。因…     

The influence of handling on egg production,egg shell quality and avoidance behaviour of hens

1. Egg production was similar in non‐handled and in regularly handled hens, but was reduced by handling hens unaccustomed to the procedure.

2. Handling reduced avoidance behaviour (”flightiness“) in growers and pullets but its effect declined with age and it had no influence in these hens when mature.

3. Handling affected egg shell quality; it resulted in an increased incidence of cracks and of equatorial bulges. Previous work has suggested that this defect is an indication of stressors applied at a critical period during egg formation. Therefore, handling may be a stressor.     

仙湖肉鸭A系种蛋重与蛋形指数对孵化效果的影响

将仙湖肉鸭A系种蛋按蛋重分为7组、按蛋形指数大小分为6组,在相同条件下孵化,结果表明,蛋重不仅对孵化率、死胚率影响较大,而且对受精率亦有影响。当蛋重在95～99g(D组)时,孵化效果最好,种蛋受精率96.18%,受精蛋孵化率高达83.86%,入孵蛋孵化率达80.66%。当蛋重大于110g时,种蛋受精率下降至89.74%,受精蛋孵化率下降至71.43%,入孵蛋孵化率下降至64.10%;当蛋重小于85g时,受精蛋孵化率、入孵蛋孵化率分别下降至73.02%和71.88%。蛋形指数对孵化率、死胚率影响也较大,当蛋形指数为0.66～0.74时,受精蛋孵化率达80%以上,入孵蛋孵化率达76%以上,死胚率小于15%,孵化效果较好,且与其它各组差异显著。     

新型维生素和植酸酶组合配方对产蛋鸡性能的影响

维生素和磷都是产蛋鸡的必需营养素 ,依靠饲料提供。但目前添加维生素和磷都有尚待解决的问题。产蛋鸡养殖和蛋鸡饲料生产大多使用维生素预混合饲料提供维生素。由于必须添加的维生素单体的种类和可选择的商品规格繁多、功能复杂 ,绝大多数利用计算机对饲料配方进行优化时都不包括维生素部分 ;同时多种因素造成维生素预混合饲料配方存在不合理性 ,以至在很多情况下需要再单独补加维生素Ｅ、生物素等。有些用户为降低成本 ,常随意减少添加量 ;不少产品推荐添加量范围过大 ,以及应激状态下添加量难以掌握 ;这一系列问题均造成用户添加维生素准…     

低蛋白质日粮对育肥绵羊生长性能、胴体性状及肌肉脂肪酸组成的影响

本研究旨在研究降低全混合日粮蛋白质水平对育肥期绵羊生长性能、胴体性状及肌肉脂肪酸组成的影响.试验将32只平均体重为(38.14±0.45)kg的育肥期绵羊随机分为2组,每组8个重复,每个重复2头.两组绵羊在为期10周的试验期中分别饲喂蛋白质水平为13.5％和8.5％的全混合日粮.结果:将全混合日粮蛋白质水平从13.5％...     

高铁高碘日粮对蛋品质的影响

用高铁高碘日粮饲喂产蛋母鸡,观察对蛋品质的影响。结果表明,蛋黄重、蛋黄占蛋重比略有下降,蛋白占蛋重比、哈夫单位有所上升;蛋壳占蛋重比、蛋壳厚度及蛋壳密度无明显变化。提示高铁高碘日粮不会引起蛋品质的明显下降。     

The effects of space allowance and group size on egg production traits and profitability 1

1. The productivity and profitability of two commercial strains of WL were measured simultaneously at space allowances of 0–0310, 0–0387 and 0.0464 m² per bird and in groups of three, six and 12 birds per cage.

2. Space and group effects were independent and additive, the latter being the more important in determining profitability.

3. A space allowance of 0–0310 m² per bird adversely affected production and increased food consumption, possibly the result of increased interaction between birds.

4. Depopulation at 12 to 13 months of lay was calculated to maximise average monthly egg margin over food and bird costs and to minimise the problems of egg quality associated with the aging pullet.     

The effects on egg production and egg composition of adding supplements of amino acids and/or urea or dried auto‐claved poultry manure to a low‐protein layer diet

Thirty‐five laying hens of a medium‐weight hybrid strain, aged 10 months, were given a basal diet containing 11.5% protein or the same diet supplemented with 1.54% essential amino acids and/or with two sources of nitrogen for the synthesis of non‐essential amino acids (1.15% urea or 9.7% dried autoclaved poultry manure) for an 8‐week period.

Egg production, food intake, food conversion efficiency, the gross efficiency of nitrogen conversion and the ability of hens to maintain body weight were improved by supplementation with essential amino acids (P < 0.05 or P < 0.01). Supplementation with dried autoclaved poultry manure raised food intake, total egg mass and mean egg weight (P < 0.05), but supplementation with urea alone did not result in significantly higher egg production, perhaps because it failed to increase food intake. Supplementation with essential amino acids and urea to give the equivalent of 16% protein did not result in significantly higher egg production than that obtained with urea alone. The smallest eggs were produced by hens fed on the diet supplemented with urea, and the largest by those fed on the diet supplemented with dried manure (P < 0.001).

The gross composition of eggs was not influenced significantly by dietary treatment but albumen quality was significantly lower on the basal diet and higher on the supplemented diets (P < 0.001). It was highest in eggs from hens fed on the diet supplemented with urea alone.