• Asian-Australasian Journal of Animal Sciences
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• 제25권7호
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• pp.1009-1014
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• 2012

Environmental stress boosts the levels of stress hormones and accelerates energy expenditure which subsequently imbalance the body's homeostasis. L-ascorbic acid (L-AA) has been recognized to mitigate the negative impact of environmental stress on production performances in birds. The present investigation was carried out to elucidate the effect of different dietary levels of L-AA on production performance, egg quality traits and fertility in Japanese quail at low ambient temperature. Sixty matured females (15 wks) were equally divided into three groups (20/group) based on the different dietary levels of L-AA (0, 250 and 500 ppm) and coupled with an equal number of males (1:1) obtained from the same hatch. They were managed in uniform husbandry conditions without restriction of feed and water at 14 h photo-schedule. Except for feed efficiency, body weight change, feed consumption and hen-day egg production were recorded highest in 500 ppm L-AA supplemented groups. Among the all egg quality traits studied, only specific gravity, shell weight and thickness differed significantly (p<0.05) in the present study. Fertility was improved significantly ($p{\leq}0.01$) to a dose dependent manner of L-AA. The findings of the present study concluded that dietary L-AA can be a caring management practice at least in part to alleviate the adverse effect of cold induced stress on production performance in Japanese quail.

• Asian-Australasian Journal of Animal Sciences
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• 제30권6호
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• pp.828-833
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• 2017

Objective: The study was conducted to evaluate the effects of different methionine (Met) sources on production performance, reproduction performance, egg quality and serum biochemical indices in broiler breeders. Methods: After receiving a basal diet (containing 0.25% Met) for a 2-wk pretreatment period, a total of 360 39-wk-old Lingnan yellow broiler breeders were randomly allocated to four treatments with six replicates each (15 birds per replicate). Breeders were fed with basal diets (control) or diets supplemented with DL-methionine (DLM), DL-2-hydroxy-4-methylthio butytric calcium (MHA-Ca) and coated DL-Met (CME) respectively. Results: The results showed that CME supplementation promoted laying rate and decreased feed-to-egg ratio (F/E) (p<0.05), DLM and MHA-Ca supplementation decreased F/E (p<0.05) when compared with control group. The rate of fertility, hatchability and birthrate were higher (p<0.05) in DLM, MHA-Ca, and CME groups than control group. Compared with control group, CME increased the eggshell thickness (p<0.05); MHA-Ca improved the eggshell thickness, shell ratio and eggshell strength (p<0.05). Results also showed that CME elevated the concentration of total protein in serum (p<0.05); MHA-Ca improved the concentration of calcium in serum (p<0.05). The concentration of serum uric acid in DLM, MHA-Ca, and CME groups was lower than that in control group (p<0.05). Besides, CME had higher concentrations of serum taurine, cysteine and cystanthionine (p<0.05) while MHA-Ca and DLM promoted the serum taurine concentration (p<0.05) compared with control group. Conclusion: Based on the results, it was concluded that Met supplementation could enhance the production and reproduction performance as well as the antioxidant status and egg quality of broiler breeders. In terms of improving the production performance, reproduction performance and antioxidant performance, CME was superior to DLM and MHA-Ca; but in regard to the enhancement of eggshell quality and serum Ca concentration, MHA-Ca was superior to DLM and CME.

• Asian-Australasian Journal of Animal Sciences
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• 제11권5호
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• pp.573-579
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• 1998

The effects of supplementation with mixed fodder or concentrate were investigated on the performance of a) growth of male lambs and kids grazing extensively under oil palm trees and b) reproduction of ewes and goats stall-fed with native herbage. Supplemented kids and lambs had higher average daily weight gain than controls but the effect was only significant for those which received concentrate (p < 0.05). Final body weight was only significantly different from controls for lambs supplemented with concentrate (p < 0.05). The ages at puberty, first mating, first conception and first kidding of supplemented goats were about 110 days earlier than those for controls (p < 0.05 or better). Supplemented goats had first mating and conceived at lower body weights (p < 0.01) than those in control groups. Different feeding regimes had no effects (p > 0.05) on the reproductive performance of ewes apart from highest body weight of first lambing in animals supplemented with concentrate (p < 0.05). Native herbage available under oil palm trees of 5 years old was sufficient for growth and reproduction of sheep and goats. Concentrate was better than mixed fodder as supplement for enhancing the reproductive performance of goats but both appeared to have limited effects on the performance of reproduction in ewes and growth in male kids.

• Asian-Australasian Journal of Animal Sciences
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• 제16권6호
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• pp.794-799
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• 2003

A study was conducted on 2102 records of 808 crossbred cows of various genetic groups maintained under 'All India Coordinated Research Project on Cattle' at C C S Haryana Agricultural University, Hisar, over 25 years period (1968-1993) with an objective to assess and compare the amount of percent improvement and heterotic effect for different performance traits in various genetic groups produced under this programme. Survivability sharply and significantly declined from 1/2 to $3/4^th$ bred and further from $3/4^th$ to inter-se bred. This may be due to periodic and management differences in addition to the higher level of exotic inheritance and decreased heterotic effect over the filial generations. Jersey and Holstein Friesian crosses among 1/2 breds and their 50% inheritance among $3/4^th$ and inter-se breds had highest improvement and heterosis in reproduction and production traits respectively. Among inter se bred genetic groups, BFH (I) had no recombination loss in SP and CI, while FJH (I), JFH (I) and FBH (I) had on recombination loss in AFC, LY, LL and PE. The crossbreeding of zebu cows with exotic breeds brings about spectacular improvement in comparison to the performance of zebu breed, while conventional selection over several generation would lead to only modest improvement. In addition to additive effect, there was sufficient heterosis in Jersey crosses for reproduction and Holstein Friesian crosses for production performance. Three breed crosses with exotic inheritance between 50 and 75 percent incorporating genes (25 to 50%) from both of these breeds is the best combination for stabilization.

• Asian-Australasian Journal of Animal Sciences
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• 제23권3호
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• pp.396-400
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• 2010

This experiment investigated the effects of increasing dietary vitamin E (VE) on production performance and egg quality traits of Indian reared Kadaknath (KN) hens. One hundred and eighty (180), day old female KN chicks were randomly distributed to three dietary treatment groups for a period of 30 weeks. Each treatment comprised three replicates, each containing 20 chicks. The basal diet ($T_1$) contained 15 IU VE/kg and the two experimental diets were supplemented with 150 and 300 IU VE/kg (diets $T_2$ and $T_3$, respectively). DL-${\alpha}$-tocopherol acetate was used as the source of VE. All chicks were provided feed and water ad libitum. Production performance in terms of body weight, egg weight and hatchability did not differ significantly (p>0.05), whereas sexual maturity, egg production and fertility differed significantly (p<0.05) in $T_2$ compared to the other two groups. Egg quality traits in terms of albumin weight, yolk weight, shell thickness, albumin index and yolk index did not differ significantly (p>0.05), whereas the Haugh unit score was significantly higher (p<0.05) in $T_2$ than the control ($T_1$) and high dose treatment group ($T_3$). From this study, it can be concluded that lower levels of dietary VE may be beneficial for production performance and Haugh unit score but have no effect on egg quality traits in Indian reared KN hens.

• Animal Bioscience
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• 제36권6호
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• pp.899-907
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• 2023

Objective: The better understanding of laying pattern of birds is crucial for developing breed-specific proper breeding scheme and management. Methods: Daily egg production until 50 wk of age of six chicken breeds including one layer (White Leghorn, WL), three dual-purpose (Rhode Island Red, RIR; Columbian Plymouth Rock, CR; and Barred Plymouth Rock, BR), one synthetic dwarf (DY), and one indigenous (Beijing-You Chicken, BYC) were used to characterize their clutch traits and egg production. The age at first egg, egg number, average and maximum clutch length, pause length, and number of clutches and pauses were calculated accordingly. Results: The egg number and average clutch length in WL, RIR, CR, and BR were higher than those in DY and BYC (p<0.01). The numbers of clutches and pauses, and pause length in WL, RIR, CR, and BR were lower than those in DY and BYC (p<0.01). The coefficient variations of clutch length in WL, RIR, CR, and BR (57.66%, 66.49%, 64.22%, and 55.35%, respectively) were higher than DY (41.84%) and BYC (36.29%), while the coefficient variations of egg number in WL, RIR, CR, and BR (9.10%, 9.97%, 10.82%, and 9.92%) were lower than DY (15.84%) and BYC (16.85%). The clutch length was positively correlated with egg number (r = 0.51 to 0.66; p<0.01), but not correlated with age at first egg in all breeds. Conclusion: The six breeds showed significant different clutch and egg production traits. Due to the selection history, the high and median productive layer breeds had higher clutch length than those of the less productive indigenous BYC. The clutch length is a proper selection criterion for further progress in egg production. The age at first egg, which is independent of clutch traits, is especially encouraged to be improved by selection in the BYC breed.

• Asian-Australasian Journal of Animal Sciences
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• 제6권4호
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• pp.549-553
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• 1993

In 1985, fifty Jersey cows were imported to Pakistan from United States of America (USA). This paper compares milk production and reproduction performance of imported cows and their daughters under USA and Pakistan conditions. The imported cows which had yielded 5,858 kg, of milk (305 d lactation) in the USA produced only 3,192 kg, at NARC. The milk production of their daughters averaged 2,617 kg, being 22% lower than their mothers under the same environment at NARC. Year and season of calving had no significant effects on milk production. Average milk production of the first lactation was 10% lower than the mean of the second, third and fourth lactations, but, the differences between lactation means were non-significant. Mean calving interval in the USA was 385 days, whereas the same cows had a longer (p<.01) calving interval of 490 days at NARC. The calving interval of the daughters was longer (452 d; p<.01) than their mothers calving interval in the USA, and shorter (p<.01) than their mothers calving interval in Pakistan. The low age at first calving suggests that locally born Jersey cows were not reproductively disadvantaged by the local environment and nutrition, suggesting the adaptability of this breed in the new environment.

• 한국동물생명공학회지
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• 제35권1호
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• pp.2-11
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• 2020

Assisted reproductive technologies (ART) merely depend on improving the oocyte maturation and their developmental competence to produce good quality embryos. Oocyte maturation passes through long and complex molecular steps starts from the early embryonic life and ends with sperm fertilization. Oocyte developmental competence can be attained by improving the nuclear and cytoplasmic mechanisms together with some epigenetic maturation. In this review, we highlight the cornerstones of oocyte maturation on both nuclear and cytoplasmic levels. Interfering or supporting these molecular mechanisms would help in the development of novel regulating agents for reproductive performance of humans and livestock species.

• Asian-Australasian Journal of Animal Sciences
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• 제13권2호
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• pp.182-187
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• 2000

Forty-two Holstein cows (21 multiparous) were assigned by calving date and parity to three dietary sequences to evaluate the effect of time of initiating fat supplementation to diets on lactation and reproductive performance. The dietary sequences were: 1) control, no supplemental fat from 1 to 98 days in milk (DIM) ; 2) control diet from 1 to 28 DIM then 3% supplemental fat (calcium salts of long-chain fatty acids) from 29 to 98 DIM; or 3) 3% supplemental fat from 1 to 98 DIM. Feeding supplemental fat did not enhance mean milk and 4% fat corrected milk (FCM) yields, but efficiency of FCM production was higher for cows fed supplemental fat. Milk fat percentage was unchanged whereas milk protein percentage was depressed with fat supplementation. Feeding supplemental fat reduced DMI and energy balance but there were no differences among treatments on time to resumption of ovarian cyclicity or conception rate to first service. Concentrations of progesterone during the first two ovulatory cycles tended to be greater in the fat-supplemented groups. Feeding supplemental fat starting at either parturition or 29 DIM increased efficiency of FCM production, but did not greatly enhance reproductive performance.

• Asian-Australasian Journal of Animal Sciences
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• 제17권2호
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• pp.283-300
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• 2004

Currently commercial dry sows are housed in individual stalls and subject to restricted feeding. These sows often show stereotypic behaviours which increase their maintenance energy requirement. Group housing is desirable to improve animal welfare and public perception. However, under restricted feeding systems, group-housed dry sows are also aggressive. The feed intake of these sows is variable, depending on their social rank, which results in different milk production and variable piglet performance. These problems can be solved by ad libitum feeding systems, but the large capacity of intake by dry sows will not allow this feeding system to be practical as high feeding level during pregnancy can reduce reproduction performance of sows. Current research indicates that feeding high fibre diets to dry sows enables sows to be fed ad libitum, but the effect of dietary fibre on feed intake and nutrient utilisation is dependent on the quality of fibre sources. Most research has focused on sugar beet pulp, straw, lucerne meal and by-products, but there is a need to identify and evaluate some widely available and cheap fibre materials and feed grains for developing the best strategy to control nutrient intake of dry sows while feeding ad libitum.