Научная статья на тему 'Сommunication of parameters of hatching eggs with hatchability and sex determination of birds'

Сommunication of parameters of hatching eggs with hatchability and sex determination of birds Текст научной статьи по специальности «Биологические науки»

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Ключевые слова
BIRD / CHICKS / DETERMINATION / GOSLING / HATCHABILITY OF EGGS / SEX / TURKEY / YOUNG / ПТИЦА / ИНДЮШАТА / ГУСЯТА / ВЫВОДИМОСТЬ / ПОЛ / ДЕТЕРМИНАЦИЯ

Аннотация научной статьи по биологическим наукам, автор научной работы — Maltsev A., Omarkozhauly N., Senkebayeva D.

The purpose of this research was to study of effect of periods of storage of eggs before incubation, their shape, mass and density on hatchability, and sex ratio. The increaseof hatchability and early detection of sex determination of young birds create opportunitiesfor differentiation of their keeping and feeding that will help to reduce the cost of poultry products and increase of industry profitability. Interconnection of hatchability and by the studied parameter. Sex of pauls has been determined by Japanese method.According to the results of study of incubation of turkeys eggs have been found that sue to the elongation of shelf life from 7 to 9 days, there was a decrease of hatching of young turkeys from 72.2% to 68.2%; geese eggs with a shelf life from 7-14 days from 64.6% to 55.2% with ratio change in hatching of females/males from 1.00/.02 to 1.00/1.26 up to 1.00/1.03 and 1.00/1.21 respectively. Hatchability of turkeys’ eggs with weight 80-90 g was 75.4%, geese eggs with weight 140-150 g 66.7%. Upon gaining in weight of incubated eggs of turkeys from 80 to 90 g and ratio of female/male has been increased from 1.00/0.96 to 1.00/1.11 and geese from 140 to 150 g or more to 1.00/1.06 to 1.00/1.13. When the index of shape of eggs is reduced, the hatching of young birds decreased and density of males increased. The decrease in density also reduced the hatching of young birds, but does not reflect on sex ratio.

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ВЫВОДИМОСТЬ И ПОЛОВАЯ ДЕТЕРМИНАЦИЯ НЕКОТОРЫХ ПТИЦ В ЗАВИСИМОСТИ ОТ ПАРАМЕТРОВ ЯИЦ

Повышение выводимости и раннее выявление половой детерминации молодняка птицы создает предпосылки для дифференциации их содержания и кормления, что будет способствовать снижению себестоимости птицеводческой продукции и повышению рентабельности отрасли. Целью исследования явилось изучение влияния сроков хранения яиц перед инкубацией, их формы, массы и плотности на выводимость и соотношение полов. Взаимосвязь выводимости и половой дифференциации с параметрами яиц определяли их инкубацией в контрольных лотках, различающиеся лишь по изучаемому параметру. Пол молодняка определяли японским методом. По результатам исследования инкубации яиц установили, что по мере удлинения сроков хранения яиц индеек с 7 до 9 дней наблюдалось снижение выводимости молодняка с 72,2 до 68,2%; яиц гусынь с 7 до 14 дней – с 64,6 до 55,2% при изменении соотношения в выводе самок/самцов с 1,00/1,02 до 1,00/1,26 и с 1,00/1,03 до 1,00/1,21 соответственно. Выводимость яиц индеек массой 80-90 г составила 75,4%, яиц гусынь массой 140-150 г – 66,7%. По мере увеличения массы инкубируемых яиц индеек с 80 до90 г и более соотношение самок/самцов возрастало с 1,00/0,96 до 1,00/1,11, гусей с 140 до 150 г и более с 1,00/1,06 до 1,00/1,13. При снижении индекса формы яиц ухудшалась выводимость молодняка при возрастании удельного веса самцов. При снижении плотности также наблюдалось ухудшение выводимости, но не отмечалось сдвигов в соотношении полов.

Текст научной работы на тему «Сommunication of parameters of hatching eggs with hatchability and sex determination of birds»

DOI: https://doi.org/10.23670/IRJ.2018.78.12.035

ВЫВОДИМОСТЬ И ПОЛОВАЯ ДЕТЕРМИНАЦИЯ НЕКОТОРЫХ ПТИЦ В ЗАВИСИМОСТИ ОТ

ПАРАМЕТРОВ ЯИЦ

Научная статья

Мальцев А.1, Омаркожаулы Н.2, Сенкебаева Д.3' * 3 ORCID: 0000-0002-3248-0550, 1 ФГБНУ «Сибирский научно-исследовательский институт птицеводства, Омск, Россия;

2' 3 Казахский агротехнический университет имени С. Сейфуллина, Астана, Республика Казахстан

* Корреспондирующий автор (dilor1986[at]mail.ru)

Аннотация

Повышение выводимости и раннее выявление половой детерминации молодняка птицы создает предпосылки для дифференциации их содержания и кормления, что будет способствовать снижению себестоимости птицеводческой продукции и повышению рентабельности отрасли. Целью исследования явилось изучение влияния сроков хранения яиц перед инкубацией, их формы, массы и плотности на выводимость и соотношение полов. Взаимосвязь выводимости и половой дифференциации с параметрами яиц определяли их инкубацией в контрольных лотках, различающиеся лишь по изучаемому параметру. Пол молодняка определяли японским методом. По результатам исследования инкубации яиц установили, что по мере удлинения сроков хранения яиц индеек с 7 до 9 дней наблюдалось снижение выводимости молодняка с 72,2 до 68,2%; яиц гусынь с 7 до 14 дней - с 64,6 до 55,2% при изменении соотношения в выводе самок/самцов с 1,00/1,02 до 1,00/1,26 и с 1,00/1,03 до 1,00/1,21 соответственно. Выводимость яиц индеек массой 80-90 г составила 75,4%, яиц гусынь массой 140-150 г - 66,7%. По мере увеличения массы инкубируемых яиц индеек с 80 до90 г и более соотношение самок/самцов возрастало с 1,00/0,96 до 1,00/1,11, гусей с 140 до 150 г и более - с 1,00/1,06 до 1,00/1,13. При снижении индекса формы яиц ухудшалась выводимость молодняка при возрастании удельного веса самцов. При снижении плотности также наблюдалось ухудшение выводимости, но не отмечалось сдвигов в соотношении полов.

Ключевые слова: птица, индюшата, гусята, выводимость, пол, детерминация.

СOMMUNICATION OF PARAMETERS OF HATCHING EGGS WITH HATCHABILITY AND SEX

DETERMINATION OF BIRDS

Research article

Maltsev A.1, Omarkozhauly N.2, Senkebayeva D.3

3 ORCID: 0000-0002-3248-0550, 1 Federal State Budget Scientific Institution «Siberian Scientific Research Institute of Poultry», Omsk, Russia 2' 3 S.Seifullin Kazakh AgroTechnical University. Astana, Republic of Kazakhstan

* Corresponding author (dilor1986[at]mail.ru)

Abstract

The purpose of this research was to study of effect of periods of storage of eggs before incubation, their shape, mass and density on hatchability, and sex ratio. The increaseof hatchability and early detection of sex determination of young birds create opportunitiesfor differentiation of their keeping and feeding that will help to reduce the cost of poultry products and increase of industry profitability. Interconnection of hatchability and by the studied parameter. Sex of pauls has been determined by Japanese method.According to the results of study of incubation of turkeys eggs have been found that sue to the elongation of shelf life from 7 to 9 days, there was a decrease of hatching of young turkeys from 72.2% to 68.2%; geese eggs with a shelf life from 7-14 days - from 64.6% to 55.2% with ratio change in hatching of females/males from 1.00/.02 to 1.00/1.26 up to 1.00/1.03 and 1.00/1.21 respectively. Hatchability of turkeys' eggs with weight 80-90 g was 75.4%, geese eggs with weight 140-150 g - 66.7%. Upon gaining in weight of incubated eggs of turkeys from 80 to 90 g and ratio of female/male has been increased from 1.00/0.96 to 1.00/1.11 and geese from 140 to 150 g or more to 1.00/1.06 to 1.00/1.13. When the index of shape of eggs is reduced, the hatching of young birds decreased and density of males increased. The decrease in density also reduced the hatching of young birds, but does not reflect on sex ratio.

Keywords: bird, chicks, determination, gosling, hatchability of eggs,sex, turkey, young.

Introduction

Sex is a set of genetically determined properties that determine its role in reproduction. Sex differentiation of embryo is formed when fused is affected by sex determination factors during the ontogenesisof autosomal sex chromosomes and epigenetic factors of environment.

Significant sex determination in poultry development actualizes the task on early detection of young birds of incubated young birds. Earlier differentiation of feeding and keeping of grown young by age-sex group allow it firstly to reduce the cost of feed per unit of production, which creates opportunitiesfor reducing the cost and increasing the profitability of industry reference.

Sexual differentiation of embryos of birds (W chromosome) in connection with the homozygous of male chromosomes (ZZ) is determined by females heterozygous chromosomes (ZW). Therefore, in the early days of embryos development the sex identification can be performed on gametes of female in the left gonads and after ten days it is possible to apply the methods of molecular genetics as autoscope. For example, sexual identity on 7 -9 day of development can be determined by coherence tomography from allantoic fluid of androgens and estrogens [1, P. 71].

According to the classical theory of Fischer [4, P. 47] on sexual determination of animals, the sex ratio in a large number of samples must be approach 1/1, but this ratio in small samples can move under the influence by both internal genotype and external paratypic factors. In particular, the lengthening of egg pre-incubation storage periods reduces the hatchability of young because of different life potential of embryos that increases the density of males [12, P. 84-90].

Tagirov [12, P. 84-90], Sergeyev [11, P. 30] and Ferguson [3] suggested a hypothesis about the possibility of existence of allelic forms of enzyme aromatize or female factor in W-chromosome in different populations of birds that have negative impact on viability of female chromosomes with different sensitivity to external influences (temperature, long-term storage, and etc.), which leads to displacement of sex ratio.

The issue on early sex determination of incubated young birds has a great scientificant research and practical value that allowto differentiate the technology of its growing and specificate feeding rate and diet, which is a determining factor of reduction of costs and feed per unit of production and increasing the economic efficiency of poultry production.

Materials And Methods

Brood of day old chicks was determined by their quantity and quality. To examine the relationship between hatchability and sexual differentiation with eggs parameters, eggs were placed in control trays setters, differing only by studied parameter: in the 1st experiment - on storage period, in the 2nd experiment - by weight, in the 3rd experiment-by shape, in the 4th experiment -by density. Storage periodsof eggs was controlled by date of receipt in the hatching house, weight -by weighing, shape - by calculation of diameter to length, density - by immersion in standard solutions.

Sex of day old chicks was determined by Japanese method -differentiation of rudimentary hills in the mucous membrane of cloaca. For this purpose, after 8-10 hours of hatching, turkey poult with umbilical cord and dry feathers is held on palm of the left hand upper legs, stroking the abdomen with index and middle fingers of the right hand to speed upthe first fecal. Then chick was placed on palm with head down and legs between index and middle fingers of the right hand and ring and little finger pressed his neck so that abdomen pressed against his back. At this time, the mucous membrane of cloaca is opened by the thumb finger of the left hand.

In the open vent of male turkeys on the ventral part of mucous membrane of cloaca closer to the surface there are observed a small, flexible, reddish genital hills, which are absent in females.

To determine of sex the gosling is held in the left hand and fixe his foot between middle and index fingers of the left hand, gosling head should be down and neck rest on the little finger. The vent should be stretched by thumb of the left hand, thumb and forefinger of his right hand. After that, thumb of the right hand is placed on edge of ventral part of the cloaca and opened it.

At the same time in the fold of cloaca in males is visible vestige of bead in the form of a bent size of 3-4 mm. Females in the inner fold of the cloaca are clearly visible the flat and spherical mucosal thickening. Sometimes it is enough to slightly pull the tail of gosling on the back to determine sexual organs (Fig. 1).

Sexdetermination of young birds should not exceed 16-18 hours after hatching, increase of this periodleads to modification of form of the cloacal foldsand reduce productivity.

Study on evaluation of young hatchability and sex determination was carried out on poultry farms "Ordabasy Kus"of South Kazakhstan and "Bishkulsk" of North Kazakhstan regions.

When collecting, storage and incubation of eggs the temperature and humidity conditionsrecommended for these hatcheries were reserved. At the initial stage of selection and sorting the eggs looked around topside and sorted according to storage period, weight, shape and density. The most dirty eggs and eggs with cracked or too thin shell, with calcareous nodules and marble shell, too small and too large, as well as irregular shapes were left.

In the pre-candling were determined the homogeneity of shell, volume and strength of air chamber, mobility of yolk, location of embryonic disc and reject eggs with wrong locationor blurred boundaries of air chamber, double-yolk, blood or meat clots, with broken chalaza.

Selected eggs with a clearly distinguishable in candling germinal disc of 4 mm in diameter with a slightly flattened yolk, held on both sides chalaza in a tightly liquefied protein layer were placed in trays of setter.

The incubation of eggs of white broad-breed turkeys was carried out in setters "Petersime", and egg of white Italian geese in setters "Universal" with automatically save of optimal parameters of temperature and humidity of incubation.

The results of incubation allowed to observe the connection of hatchability and sex differentiation of turkeys and geese with parameters of hatching eggs in the form of pre-incubation periods of storage, weight, shape and density.

In the first study were monitored the hatchability and sex of young from eggs with equal weight, shape and density, but with different pre-incubation periods of storage (Table 1).

Fig. 1 - Rudimentary hills in male geese

Results

Table 1 - Hatching and sex of young from eggs with different terms of pre-incubation storage

Control trays Number of eggs, pieces Period of storage, days Fertilizedegg Hatched young

sex among them

pieces % ? $

Turkey eggs

1-st 126 6 111 88,1 91 45 46

2-nd 126 8 108 85,7 89 44 45

3-rd 126 9 98 77,8 86 38 48

Goose eggs

1-st 116 7-8 95 81,8 75 37 38

2-nd 116 10-11 96 82,7 67 33 34

3-rd 116 13-14 94 81,0 64 29 35

The results of incubation, represented in Table 1, have shown a connection of hatching and sex of day-old chicks with preincubation egg storage periods. Thus, the hatching of healthy turkey poults from set eggs in amount of 126 with a shelf life of less than 6 days was 72.2% at the same time from 91 chicks where 49.5% were females, 50.5% males; with a shelf life of 8 days the hatch was 70.6% and from 89 chicks where 49.4% were females, 51.6% males; with a shelf life of 9 days of the hatch was 68.2% and from 86 chicks 44.2% were females, 55.8% males.

Hatching of healthy goslings from set in amount of 116 eggs with a shelf life of 7-8 days was 64.7% from 75 chicks where 49.3% were female, 50.7% - male, with a shelf life of 10-11 days the hatch was 57.7 % from hatching 67 chicks where46.3% were females, 53.7% males; with a shelf life of 13-14 days the hatchwas 55.2% from hatching64 chicks where45.3% were females, 54.7% males.

In the second study were studied the hatching and sex of young from eggs with different weight, excluding shelf life, shape and density (Table 2).

Table 2 - Hatching and sex of young from eggs with different weight

Control trays Number of eggs, pieces Egg weight, g Fertilizedegg Hatched young

sex among them

pieces % 2 s

Turkey eggs

1-st 126 < 80 108 85,7 94 48 46

2-nd 126 80-90 107 84,9 95 45 50

3-rd 126 > 90 96 76,2 72 35 37

Goose eggs

1-st 66 < 140 52 78,8 38 20 18

2-nd 66 140-150 55 83,3 44 21 23

3-rd 66 > 150 53 80,3 34 16 18

Hatching of turkey chicks from eggs with weight less than 80 g was 74.6% so from hatching 94 chicks where51.1% were females, 48.9% males; weight 80-90 g hatching was 75.4% and from hatched 95 chicksfemales were 47.4%, 52.6% males; weight more than 150 g hatching was 57.1% and from hatched72 chicksfemales were 48.6%, 51.4% males.

Hatching of goslings from eggs with weight less than 140 g was 57.6% from hatching 38 chicksfemales were 52.6%, 47.4% males; weight 140-150 g hatching was 66.7% and from hatched44chicks females were 47.7%, 52.3% males; weight more than 150 g hatching was51.5% and from hatched 34 chicks females were 47.0% , 53.0% males.

In the third study were studied the hatching and sex of young from eggs with different shape, excluding shelf life, weight and density (Table 3).

Table 3 - Hatching and sex of young from eggs with different shape

Control trays Number of eggs, pieces Shapeindex, % Fertilizedegg Hatched young

sex among them

pieces % 2 s

Turkey eggs

1-st 126 < 73 96 76,2 70 33 37

2-nd 126 74-76 112 88,9 94 46 48

3-rd 126 > 77 109 86,5 98 50 48

Goose eggs

1-st 66 > 65 53 80,3 45 20 25

2-nd 66 65-69 54 81,8 47 23 24

3-rd 66 < 70 53 80,3 46 24 22

Hatching of turkeys from egg with shape index of less than 73% was55.6% from hatching 70 chicks females were 47.1%, 52.9% males; with shape index 74-76% hatching was 74.6% from hatching 94 chicks where 48.9% were females, 51.1% males; with shape index more than 77% hatching was 77.8%, from hatching98 chicks 51.0% were females, 49.0% males.

Hatching of goslings from egg with shape index of less than 65% was68,2% from hatching 45 chicks females were 44,4%, 55,6%males; with shape index 65-69% hatching was 71,2% from hatching47 chicks where 48,9% were females, 51.1% males; with shape index more than 70% hatching was 69,7%, from hatching46 chicks 52,2% were females, 47,8% males.

In the fourth study were studied the hatching and sex of young from eggs with different density, excluding shelf life, weight and shape (Table 4).

Table 4 - Hatching and sex of young from eggs with different density

Control trays Number of eggs, pieces Eggdensity, g% Fertilizedegg Hatched young

sex among them

pieces % 5 S

Turkey eggs

1-st 126 <1,070 108 85,7 76 37 39

2-nd 126 1,071-1,080 111 88,1 91 46 45

3-rd 126 >1,081 114 90,4 93 48 45

Goose eggs

1-st 66 <1,085 53 80,3 42 21 21

2-nd 66 1,085-1,090 54 81,8 46 22 24

3-rd 66 >1,090 53 80,3 44 22 22

Hatching of turkeys from egg with density of less than 1,070 g% was60,3% from hatching 76 chicks females were 48,7%, 51,3% males; with density 1,071-1,080 g% hatching was72,2% from hatching 91 chicks, where 50,5% were females, 49,5% males; with density more than 1,081 g% hatching was73,8%from hatching 93 chicks 51.6% were females, 48,4% males.

Hatching of goslings from egg with density of less than 1,085 g% was63,6% from hatching 42 chicks females were 50,0%, 50,0% males; with density 1,085-1,090 g% hatching was 69,7%, from hatching 46 chicks, where 47,8% were females, 52,2% males; with density more than 1,090 g% hatching was 66,7%, from hatching 44 chicks 50,0% were females, 50,0% males.

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Discussion

Embryogenesis and sex differentiation are related to both genetic and paratypic factors of hatching eggs parameters in the form of pre-incubation periods of storage, weight, shape and density.

Internalgenetic factors and external epigenetic factors are influenced on the formation of sex of young bird. During the early embryogenesis at the genetic level there is a sex differentiation of zygote caused by homozygous or heterozygous gametes, which have affected also by paratypic factors.

Ismailov and others [7, P. 28-30] in their research syndicate the connection embryogenesis and sex differentiation with genetic and paratypic factors of hatching eggs and the establishment of parameters of a healthy young goslings with high growth. So, Tagirov [12, P. 84-90] found a significant shift of sex ratio towards males formation in hatching of eggs Rhode Island Red after their storage within 15-21 days.In his studies the number of males is almost twice higher than females. Similar results were obtained in experiments of Sergeyev [11, P. 30], that carried out in the experimental farm "Borki" the ratio of females/males of goslings hatchin from eggs with a shelf life of 4-8 days was - 1.00/0.95; 9-12 days - 1.00/1.01; 13-15 days -1.00/1,024-1,028. Ferguson [3], also notes that the increase of pre-incubation period of storage of eggs increases the output of proportion of males, because accumulated aromatase allelic of enzyme W has negative impact on density of female chromosomes.

Dependence of hatchability and embryos sex from weight of eggs of geese and turkeys with a high output of a healthy day old chicks in our study established from the average weight of eggs in the predominance of males in hatching. Similar results were obtained in studies of Rolnick [10, P. 34-38], who points out that the weight of eggs ofmales weighted 0.2-0.4 grams more than eggs from females. Dyadichkina [2, P. 12-16], has established a direct relationship between the density of eggs аnd eggshell thickness.

Interconnection of hatchability and sex differentiation with parameters of eggs confirmed by studies of Francis and Barlow [5, P. 673-675], Holmgren and Mosegaard [6, P. 910-925] on the impact of sex determination in the early stages of embryogenesis temperature and acidity (pH), buffer and salinity of environments. Romanoff [8, P. 643], Rolnik and Portenko [10, P. 34-38] indicate the impact of paratypic factors of environmental on the formation of sex cells, concentration of estrogen, gas production rate and metabolic processes in different steps of embryogenesis.

Thus, the results of study of communication of parameters of hatching eggs of geese and turkeys with hatchability and sex differentiation of young animals are agreed with the earlier results of study and indicate the possibility to influence on hatchability of young and sex differentiation paratypic factors.

Conclusion

Hormonal methods, giving the opportunity to determine sex of embryo in the early embryogenesis at 3.5-4.5 hours by biopotentials gonads and level of estrogen is acceptable poor in scale of production.

Extension of pre-incubation storage of egg has reduced biocapacity of embryo development. The dependence of hatchability and sex of embryos from egg weight demonstrated by a higher hatching of a healthy day-old chicks from the average egg weight. With the increase of value of egg shape index was increased hatching of day-old chicks and the ratio of hatching of females/males, on the contrary, was decreased. Densityreduction of eggs was decrease the hatching of day-old chicks. The tendency of decrease in hatching and increase of age-specific weight of males was established with lengthening

shelf life of eggs.

Конфликт интересов Conflict of Interest

Не указан. None declared.

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