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1.
Evidence of sperm storage in the female ostrich   总被引：2，自引：0，他引：2  
OBJECTIVE: To determine the length of time following mating that fertile eggs can be laid by an ostrich (Struthio camelus). DESIGN: A clinical reproductive problem in a pair of breeding ostriches provided the opportunity to mate the birds at intervals of 5 to 8 days and assess the fertility of the eggs laid. PROCEDURE: Following prolapse of the phallus of the male ostrich during the breeding season, the pair were immediately separated. The hen was reintroduced to the cock at intervals of 5 to 8 days over a 6 week period for supervised mating. Records were kept of dates of mating and laying, number of eggs laid, egg weights, and fertility determined by candling after 2 weeks incubation. RESULTS: Over the 6 week period, 10 eggs were laid, of which 8 were fertile and 2 infertile. Fertile eggs weighed 1020 to 1285 g (mean 1143). The two infertile eggs weighed 1160 and 925 g. Six fertile eggs were laid 2 to 7 days after mating. The remaining two fertile eggs were laid the same days that mating occurred, suggesting that fertilization resulted from the last matings 5 and 8 days previously, or from earlier matings. CONCLUSION: Sperm storage occurs in ostrich hens and fertile eggs can be laid for at least 5 to 8 days after copulation. Further studies are required to demonstrate the maximum period during which stored sperm are capable of successful fertilization.  相似文献   

2.
1. The effects of two mating ratios (8:1 and 12:1 females:males) on bird health, egg production and quality, fertility (employing macroscopic and microscopic techniques) and hatchability were examined for pheasants (Phasianus colchinus) on a commercial game farm, to provide a baseline data set for production of pheasants under specific conditions. 2. Mating ratio did not significantly affect mortality or pathology of breeding birds. 3. Egg production was significantly higher for the 8:1 mating ratio over the first 5 weeks of the trial but this difference disappeared during the second half of the trial. 4. Incidence of rejected eggs increased as the season progressed, mainly due to poor shell quality, but it was not significantly affected by mating ratio. 5. Fertility of eggs produced from birds under an 8:1 mating ratio was consistently and significantly 4% higher than fertility of eggs from the 12:1 mating ratio. The incidence of eggs showing no sign of mating (no sperm) was twice as high for the 12:1 pens (13.7% of the sample). There was good agreement between macroscopic and microscopic examination of fertility in eggs. Higher fertility in the 8:1 pens appeared to be related to a higher proportion of the females being recruited and mated. 6. Hatchability was significantly improved by adopting an 8:1 mating ratio, presumably due to the higher fertility of the eggs. Candling of the eggs improved hatchability but only for the 12:1 pens probably because more clear eggs were removed from the tray.  相似文献   

3.
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4.
1. The hatching success and embryonic mortality of 724 lesser rhea eggs from 12 farms in northern Patagonia, Argentina were monitored during the 2000 breeding season. 2. Average infertility was 24.5%, embryonic mortality was 33.5%, hatchability of fertile eggs was 66.5% and the neonatal mortality was 57.0%. There were large variations between different farms. 3. Bacterial contamination was high and egg hatchability was also affected by the occurrence of oedematous and malformed embryos. 4. No significant relationships were found between embryonic loss, duration of egg storage, initial egg weight or weight loss of hatched and failed eggs. 5. The low productivity on lesser rhea farms is caused not only by embryonic mortality but also by a high incidence of infertile eggs and neonatal mortality. 6. Bacterial infection may not have been the most important cause of incubation failure, indicating that nutritional deficiencies and inbreeding may play an important role in the productivity of these farms.  相似文献   

5.
(1) This research was carried out to investigate changes in egg production and hatchability as influenced by age and breeding season of 10 trios (two females, one male) of ostrich (Struthio camellus) during 1998 to 2002. (2) Breeding season affected number of eggs laid per female per season, average egg weight, length of laying period and clutch sequence. (3) The number of eggs laid per female per season was 25 in the first breeding season and 57 by the fifth breeding season. The laying period lasted 169 d in the first season whereas it was 210 d by the fifth season. The breeding season became longer year by year. (4) The number of clutches was two in the first season, three in the second and 4 in the later breeding seasons: the mean interval between cycles was 9 to 10.6 d and the mean number of eggs in one cycle varied from 12 to 14.4. (5) The breeding season affected the hatchability of fertile eggs, chick weight at hatching, hatchability of total eggs, fertility, malpositioned embryos, deformed chicks and assisted chicks during hatching. The first 4 variables increased and the last three decreased, with each breeding season. (6) Weight loss of eggs and length of incubation were unaffected by the breeding season. Hatchability which was 64.3% in the first season increased progressively and reached 73.1% in the fifth breeding season.  相似文献   

6.
1. From 1992 to 2003, selected (S) and control lines (C) of the laying Brown Tsaiya duck (Anas platyrhynchos) were simultaneously maintained under the same standardised conditions of feeding and management. 2. The selection objective was to increase the number of fertile eggs after a single artificial insemination (AI) with pooled Muscovy semen. From generations G1 to G11, 2452 and 2022 female ducks, in S and C lines, respectively, were measured and recorded. In the S line, the percentage selected varied between 20.2 and 34.3% in females and between 7.2 and 20.8% in males. 3. Selection for number of fertile eggs had a correlated effect of increasing the parameter tau of the logistic curves which fitted the daily variations (d 2 to 15) in fertility or hatchability on the basis of eggs set. The differences S-C for the estimates of the times of half maximal fertility and hatchability increased by 0.41 and 0.37 d per generation between G1 and G11, respectively. 4. The highest increases of fertility per day rates after a single AI were observed between d 5 and 11. Moreover, in the selected line, fertility rate was higher than, or equal to, 90% in d 2 from G8. The same tendencies were observed for the changes in the evolution of hatchability on the basis of eggs set. 5. Selection increased fertility and hatchability according to the egg set rates, especially for d 2 to 8 after AI. Hatchability of fertile eggs was not impaired, confirming that selection for one AI per week was possible in this strain of laying ducks.  相似文献   

7.
1. Twenty-three lines of chickens, obtained from grandparent stocks of 4 Australian breeding companies, were analysed to determine the incidence of early embryonic mortality attributable to chromosome abnormalities. The lines included 10 layer strains, consisting of 6 White Leghorn, 2 New Hampshire and 2 Australorp lines, and 13 broiler lines. 2. A total of 10,730 eggs was examined after 3 d incubation; of these 9746 (90.8%) were fertile. Abortive embryonic development was observed in 1379 (14.1%) of the fertile eggs. This consisted of 952 (69.0%) dead and dying embryos, including 646 malformed and 427 (31.0%) membranes without embryos. 3. Early embryonic mortality was found to vary from 9.8 to 26.8% (average 16.4%) in broiler lines and from 8.0 to 27.9% (average 11.9%) in layer lines. 4. Among 898 abortive embryos analysed, 112 had abnormal chromosomes consisting of 27 haploids, 38 haploid-euploids, 24 triploids, 16 diploid-polyploids, 4 aneuploids, 2 tetraploids and 1 translocation. 5. In broilers and layers respectively, chromosome abnormalities were responsible for 4.4 to 28.1% (average 11.8%) and 7.4 to 25.0% (average 13.4%) of the early embryonic mortality. 6. The overall frequency of chromosome abnormalities in all fertile eggs varied from 0.7 to 3.7% for the broiler lines and 0.7 to 3.4% for the layer lines.  相似文献   

8.
(1) Fertile hatchability was superior from a broiler breeder flock at 29 weeks of age than at 68 weeks of age because of decreased mortality at all stages of embryo development. (2) Eggs that were either turned or not turned during the 0 to 7 d, 8 to 14 d and 15 to 18 d periods in the 8 possible combinations showed that the absence of turning from 0 to 7 d of incubation caused a decrease in fertile hatchability and an increase in all stages of embryonic mortality, and an incidence of Malposition II (head in small end of shell) that was more pronounced in a 68-week-old flock than a 29-week-old flock. (3) When eggs from 33- and 35-week-old broiler breeder flocks were either turned or not turned from 0 to 2 d, 3 to 4 d, 5 to 6 d or 7 to 8 d in the 16 possible combinations, the absence of turning from 3 to 8 d, or 0 to 2 d alone or in combination with other time periods reduced fertile hatchability and increased embryonic mortality and percentage of Malposition II. (4) The most critical period for turning commercial broiler hatching eggs during incubation was from 0 to 7 d with the single most critical 2-d period being 0 to 2 d.  相似文献   

9.
1. The effects of sight barriers in the pens of breeding ring-necked pheasants were investigated on a commercial game farm over a 10-week laying season. 2. Reproductive performance was recorded as egg production, numbers of eggs rejected for hatching together with measures of fertility, embryonic mortality and hatchability for 11 pens with barriers and 11 pens that were left open and acted as controls. 3. Egg production per pen and the numbers of rejected eggs were not significantly affected by the presence of the barriers. 4. Fertility was significantly higher and persisted for longer in the barrier pens, particularly towards the end of the laying season. 5. Embryonic mortality was unaffected by the presence of the barriers but hatchability was significantly lower in the open pens, which was associated with lower levels of fertility. 6. Establishing sight barriers in breeder pens for commercial pheasants would appear not only to offer improved welfare but also significant commercial advantages.  相似文献   

10.
1. Eggs were stored for two different times at varying temperatures. The effects on hatchability, chick weight at hatch and hatching time were examined in two broiler breeder lines from 33 to 58 weeks of age. 2. Short storage (1 to 3 d). Storage at 20 degrees C compared with 16.5 degrees C reduced hatchability of all eggs set. No effect was observed on hatchability of fertile eggs, hatching time or chick weight. 3. Long storage (9 to 11 d). Storage at 16.5 degrees C compared with 10 degrees C decreased both hatchability of fertile eggs and chick weight at hatch. Incidence of early embryonic death increased and incubation time decreased at 16.5 degrees C compared with 10 degrees C. 4. Chicks from morning eggs were heavier than those from afternoon eggs irrespective of storage conditions. 5. Hatchability (all eggs set and fertile eggs) and chick weight varied with hen age irrespective of storage conditions. During long storage, hatching time varied with hen age independently of breeder line, storage temperature or egg laying time. 6. Hatchability (all eggs set and fertile eggs) was higher in line A than in line B. Line B eggs hatched later and produced heavier chicks than line A eggs irrespective of storage time.  相似文献   

11.
Samples of 20 hatching eggs from each of 2004 individual pedigreed pullets were incubated and hatchability recorded. Unhatched eggs were examined for evidence of embryo development and classified as infertile, early embryonic death (died 0–10 d) or late embryonic death (died 11–22 d). Variance analysis yielded a mean heritability value for hatch of all eggs of approximately 0.30. Heritability values for early and late embryo mortality were subject to larger errors but there was a tendency among the estimates of h 2 8 for late embryo mortality to be higher than those for early embryo mortality.

The genetic correlations between hatchability and both early and late embryonic mortality were high and negative as was to be expected from part × whole correlations. However the genetic correlation between early and late embryonic mortality was also consistently positive indicating common genetic determination of these two independent traits.  相似文献   


12.
In several countries, there is a well-developed market for Red-Legged partridge (Alectoris rufa) eggs for incubation. Although Red-Legged partridge eggs produced at game farms are sold with a guaranteed average hatchability, there is a marked seasonal variation in fertility and hatchability. Therefore, an average incubating hatchability value cannot be generalized across the whole breeding season. In this research, the influence that the laying date has upon the fertility and hatchability of incubated eggs and the hatchability of the fertile eggs incubated at a farm of Red-Legged partridge was analyzed. It was found that the laying date did indeed influence the fertility and hatchability of the incubated eggs. Fertility and hatchability were greater in the eggs set in the incubator between mid February and late March than those of the eggs set in late April and early May. Hatchability of fertile eggs was greater in the eggs set in the incubator in mid March and lower in the eggs set in late April. The higher values obtained during the middle of the laying period and the lower ones obtained at the end of the laying period cause the game farms’ need to inform their potential customers of the eggs’ expected hatchability as a function of their laying date.  相似文献   

13.
The ostrich industry experiences a high rate of embryonic mortalities during artificial incubation of eggs. Embryonic deaths were studied from data recorded on 37,740 fertile eggs incubated artificially during the 1998-2005 breeding seasons. Roughly 10,000 eggs that sustained embryonic mortalities were classified according to the stage and nature of death, i.e. before 21 days of incubation, after 21 days of incubation, deaths after pipping and rotten eggs. Although infection may have played a role in approximately 1300 rotten eggs, no detailed knowledge of the pathogens involved was available. The remainder of deaths could not be related to pathogens and the deaths were thus generally referred to as non-infectious. The overall level of embryonic mortality in all the eggs studied was 28.5 %. Overall embryonic mortality was affected by incubator, with higher levels (57.0 %) found in eggs incubated in an African Incubator and also in eggs that were transferred between incubators during incubation (38.1%). Overall embryonic mortality also increased in eggs produced by older females. Eggs produced in the autumn had the highest level of embryonic mortality at 53.6 %, whereas eggs produced in the winter had a marginally higher level of embryonic mortalities of 29.2 % compared with eggs produced during summer (27.4 %). Eggs produced by South African (SA) Black males crossed to Zimbabwean Blue females had high levels of embryonic losses of 45.7 %. The embryonic mortality of eggs produced by SA Blacks or Zimbabwean Blue breeding birds subjected to pure breeding was similar at approximately 33-34 %, but embryonic mortality was improved in eggs produced by Zimbabwean Blue males crossed to SA Black females (27 %). Embryonic mortality was increased in eggs that were set directly (32.0 %) or subjected to longer than 6 days of storage (43.5 %). Embryonic mortality was affected by year. The results that were obtained will assist in determining non-infectious factors that have a negative effect on hatching success. Steps can thus be taken to eliminate such factors that may compromise hatching success.  相似文献   

14.
Pullets that were fed diets containing 0.53 per cent and 0.42 per cent lysine grew at a slower rate and matured later than those that were given adequate amount of lysine. The latter pullets converted their food more efficiently than did the restricted pullets with the exception of the group fed the ration containing 0.53 per cent lysine for the first 12 weeks. The restricted pullets consumed less food during the growing period. A smaller bird was produced on less food. The restricted pullets were also lighter than the control pullets at the end of the laying season. A saving in food costs is indicated because the smaller hen would require less food for maintenance.

There was a higher mortality in the pullets fed a ration containing 0.53 per cent lysine during the growing period. The mortality in the group fed the ration containing 0.42 per cent lysine from 7 to 22 weeks of age was the same as that of the control. There were no differences in mortality during the laying season that could be related to methods of rearing the pullets.

During the laying season, the highest rate of lay was obtained from hens which had been fed the ration containing 0.42 per cent lysine from 7 to 22 weeks of age. Hens fed on the ration containing 0.53 per cent lysine from o to 4, 8 or 12 weeks of age showed no improvement in rate of lay as compared with controls.

Hens fed the ration containing 0.42 per cent lysine from 7 to 22 weeks laid fewer small eggs at the beginning of the laying season than did hens receiving adequate amounts of lysine throughout or fed the ration containing 0.53 per cent lysine from o to 4, 8 or 12 weeks. The hens fed the latter ration laid smaller eggs throughout the laying season.

No differences were found between the fertility, hatchability or embryonic mortality of eggs obtained from hens fed on lysine deficient diets during growth and those fed on diets adequate in lysine.  相似文献   


15.
Embryonic mortality is a significant problem plaguing the hatching success. Its early forms are especially hardly distinguishable from true infertility. Propidium iodide (PI) staining of the germinal disc combined with outer perivitelline layer (OPVL) sperm counting was used for the determination of 'true' fertility of duck eggs in two different experiments: fertility investigation on fresh, unincubated eggs of Hungarian ducks and on incubated eggs of a crossbred, selected as 'infertile' at the 7th day of incubation. Examination of the relationship between OPVL sperm count and fertility seems to be an adequate tool for checking the effectiveness of insemination programmes and the fertilising capacity of poultry spermatozoa. The proportion of fertile eggs was around 50% when the number of OPVL sperm was between 0.1 and 0.2 spermatozoa/mm2. Ninety-nine percent of the eggs containing > 0.3 OPVL sperm/mm2 were fertile and all of the eggs containing < 0.05 sperm/mm2 were infertile. To assure the accuracy of fertility prediction by OPVL sperm counting, PI staining of the germinal disc was used to determine fertility in uncertain cases. Identification of very early embryonic mortality, i.e. that occurring before oviposition, is very difficult. The use of a dissecting microscope for the assessment of real fertility is suitable in most of the cases, while PI staining of the germinal discs proved to be more reliable for detecting very early embryonic death. The combination of the two methods proved to be a useful tool for detecting the 'true' fertility of duck eggs of different breeds.  相似文献   

16.
The present study compares embryonic mortality between lines selected for different production traits, assesses the effects of inbreeding of the hen and embryo on embryonic mortality, and estimates genetic parameters of embryonic mortality. The experiment covered 10 generations of selection for increased egg number (EN), egg weight (EW), egg mass (EM) and a control line (C). The data included age at 1st egg, egg number and egg weight. Percent fertile eggs (PF), percent hatched of fertile eggs (PHF) and percent dead chick at hatch (PDH) were also recorded for the selected parents. PDH was higher in the selected lines than in the control line. Among the selected lines, the EW line had the highest embryonic mortality. Inbreeding of the hen and embryo had no significant effect on PDH in any of the lines. Estimates of heritability for PDH were 0.10+/-0.05, 0.02+/-0.02, 0.03+/-0.02 and 0.02+/-0.02 for lines EN, EW, EM and C, respectively. There was a positive genetic correlation between egg weight and PDH in line EW indicating that selection for increased egg weight was associated with high embryonic mortality. A negative genetic correlation between PDH and reproductive traits in line EN was observed, which is favourable.  相似文献   

17.
In an 18-month study the domestic fowl in 42 households in three traditional management systems were recorded to determine reproduction, growth and mortality parameters. There were significant differences for all systems combined in the number of clutches started per month with the lowest number being laid in the cool dry season of January and February. Mean number of eggs per clutch was 8.8; the number of eggs increased significantly throughout the career of the hen but there were no significant systems differences. Egg weight was 34.4g there being no significant differences due to age of hen or system. Intervals between clutches were 92 days, annual egg output was 35 per hen (assuming that birds were present in the flock for a year) equivalent to about 118% of mean adult hen body weight: hens actually in the flocks during the study had produced 2.1 clutches on average. Hatchability of eggs was 69.1% there being significant seasonal and systems differences in this parameter, lowest hatchability being in the hot dry season (March to June) and in the rainfed millet system. Mortality rates to eight weeks were 56% of chicks hatched. Growth to 10 weeks averaged 4g/d. Mature cocks weighted 1.60 kg and mature hens 1.02 kg: hen weights were significantly affected by reproductive state, laying hens being heavier than both incubating hens and those rearing chicks, while those rearing chicks were heavier than those incubating. Suggestions for improving productivity are made.  相似文献   

18.
不同限饲水平对产蛋期肉种鸭生产性能的影响   总被引：2，自引：0，他引：2  
本研究旨在探讨不同限饲水平对产蛋期肉种鸭生产性能和孵化指标的影响。试验选取 ４０周龄父母代 ＳＭ３樱桃谷种鸭 ３２００只（母鸭 ２６００只,公鸭 ６００只）,随机分成 ４组,每组 ５个重复,每个重复 １６０只鸭（母鸭 １３０只,公鸭 ３０只）。以玉米 －豆粕 －小麦型配合饲料（代谢能 １１．５０ＭＪ／ｋｇ,粗蛋白质 １８．００％）为基础饲粮。Ｔ１组日饲喂料量最大,为每只鸭 ２２５ｇ,其他组依次降低 １５ｇ,分别为 ２１０（Ｔ２组）、１９５（Ｔ３组）和 １８０ｇ（Ｔ４组）,试验期 ３５ｄ。结果表明：１）当日饲喂料量由２２５ｇ下降到２１０ｇ时,公、母鸭的体增重均显著下降（Ｐ＜０．０５）,产蛋率略有上升,蛋重略有下降,但二者变化均不显著（Ｐ＞０．０５）,当日饲喂料量继续下降到 １９５和 １８０ｇ时,与日饲喂料量 ２２５ｇ时相比,公、母鸭体增重、产蛋率和蛋重均显著下降（Ｐ＜０．０５）;２）经回归分析,公、母鸭体增重、产蛋率、蛋重与日饲喂料量有显著的直线或二次曲线关系（Ｐ＜０．０５）,产蛋率与蛋重之间也有显著的二次曲线关系（Ｐ＜０．０５）;３）日饲喂料量对种鸭死淘率及种蛋合格率、受精率、健雏率、入孵蛋孵化率和受精蛋孵化率均无显著影响（Ｐ＞０．０５）。结果提示,适当限制饲喂料量可降低体增重,提高产蛋率,但过度限饲会影响生产性能。  相似文献   

19.
A study was conducted to evaluate effects of cassava root chips (CRC) andMoringa oleifera leaf meal (MOLM) inclusion in layer rations on egg laying performance, egg quality parameters, fertility, and hatchability. One hundred twenty Dominant CZ layers, 22 wk of age, and 12 cocks were used and equally divided into 4 dietary treatments with 3 replications. Treatment rations contained CRC and MOLM [i.e., T1 (0% CRC and 0% MOLM), T2 (50% CRC and 0% MOLM), T3 (0% CRC and 5% MOLM), and T4 (50% CRC and 5% MOLM)]. The CRC and MOLM were used to substitute for 100% corn grain and 5% soybean meal, respectively. Hens were weighed at the start and end of the experiment and BW change was calculated. Data on DM intake, hen-day egg production, egg weight, and egg mass were recorded daily. Egg quality parameters were determined at an interval of 15 d on 4 eggs per replicate. Fertility and hatchability of eggs, as well as mortality of birds and embryonic mortality of fertile eggs during the incubation period were recorded. From the chemical analysis, the calculated ME content of CRC was 3,852 kcal/kg of DM and the CP content of MOLM was 28%. The DM intake of birds, hen-day egg production, egg mass, FE, and mortality rate were not influenced by treatments. Body weight change and egg weight were higher for T4 as compared with other treatments. Most external and internal egg quality parameters, especially yolk color, were improved when the diet contained MOLM. Fertility showed nonsignificant differences among treatments. However, hatchability percentage for T1 was lower than the other treatments. In conclusion, CRC at 50% of the diet, CRC replacing corn grain 100%, or MOLM at 5% of the diet replacing soybean meal can impart similar or better positive effects on egg production, egg quality parameters, eggs fertility, and hatchability of Dominant CZ layers. Thus, 50% CRC, 5% MOLM, or a combination of both can successfully be used in the diet of layers as energy and protein feed ingredients, respectively.  相似文献   

20.
1. Studies on the egg laying pattern of the semi-domesticated helmeted guinea fowl showed that the birds laid eggs between 06.00 and 20.00 h local time (05.00 to 19.00 h GMT). 2. More (67.9%) were laid in the evenings (15.00 to 20.00 h) than at any other period. 3. There were two distinct periods in the reproductive cycle: a breeding season which began in April and ended in September, and a resting or non-breeding period between October and March. 4. Sequence length was predominantly of 4 eggs and July was the month of peak egg production.  相似文献   

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