• Asian-Australasian Journal of Animal Sciences
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• v.33 no.9
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• pp.1378-1386
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• 2020

Objective: Chinese indigenous sheep breeds can be classified into the following three categories by their tail morphology: fat-tailed, fat-rumped and thin-tailed sheep. The typical sheep breeds corresponding to fat-tailed, fat-rumped, and thin-tailed sheep are large-tailed Han, Altay, and Tibetan sheep, respectively. Detection of copy number variation (CNV) and selection signatures provides information on the genetic mechanisms underlying the phenotypic differences of the different sheep types. Methods: In this study, PennCNV software and F-statistics (F_ST) were implemented to detect CNV and selection signatures, respectively, on the X chromosome in three Chinese indigenous sheep breeds using ovine high-density 600K single nucleotide polymorphism arrays. Results: In large-tailed Han, Altay, and Tibetan sheep, respectively, a total of six, four and 22 CNV regions (CNVRs) with lengths of 1.23, 0.93, and 7.02 Mb were identified on the X chromosome. In addition, 49, 34, and 55 candidate selection regions with respective lengths of 27.49, 16.47, and 25.42 Mb were identified in large-tailed Han, Altay, and Tibetan sheep, respectively. The bioinformatics analysis results indicated several genes in these regions were associated with fat, including dehydrogenase/reductase X-linked, calcium voltage-gated channel subunit alpha1 F, and patatin like phospholipase domain containing 4. In addition, three other genes were identified from this analysis: the family with sequence similarity 58 member A gene was associated with energy metabolism, the serine/arginine-rich protein specific kinase 3 gene was associated with skeletal muscle development, and the interleukin 2 receptor subunit gamma gene was associated with the immune system. Conclusion: The results of this study indicated CNVRs and selection regions on the X chromosome of Chinese indigenous sheep contained several genes associated with various heritable traits.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.4
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• pp.529-533
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• 2003

The intake, dry matter (DM) digestibility, total mean retention time (TMRT) and weight changes were investigated in four fat tailed and four Dorper sheep fed on a maize stover crop residue. Animals were subjected to five dietary treatments, which were: 90, 135 and $180g\;DM/kgBW^{0.75}/day$ of chopped maize stover offered with urea, and in subsequent dietary treatments $180g\;DM/kgBW^{0.75}/day$ of stover supplemented with either dried bean husks or poultry manure. Although not statistically different (p>0.05) fat tailed sheep had higher maize stover intake than the Dorper sheep when expressed per metabolic body weight. The DM intake and digestibility increased significantly (p<0.001) in both sheep breeds when the maize stover offer levels were increased from 90 to $135g/kgBW^{0.75}/day$. Dorper sheep had significantly (p<0.001) higher DM digestibility and longer total mean retention times for both the liquid and solid matter than the fat-tailed sheep. Fat-tailed sheep gained 4.75 kg while Dorper sheep gained 3.75 kg over the entire experimental period. The weight change per dietary treatment was affected by the amount of maize stover and the type and amount of supplement consumed. The higher DM digestibility and longer total mean retention time in Dorper sheep shows that the breed has adapted to utilize the low quality roughage diets. An indigenous fat tailed, has the potential to ingest high volumes of fibrous feed and has higher voluntary intakes relative to its body size. The two sheep breeds are a valuable genetic resource in sub Saharan Africa that is characterized by long dry season with no readily available and affordable conventional feeds for small ruminants.

• The Korean Journal of Applied Statistics
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• v.35 no.4
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• pp.501-515
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• 2022

Despite the stylized statistical features of returns of financial returns such as fat-tailed distribution and leverage effect, no stochastic volatility models that can explicitly capture these features have been presented in the existing frequentist approach. we propose an approximate parameterization of stochastic volatility models that can explicitly capture the fat-tailed distribution and leverage effect of financial returns and a maximum likelihood estimation of the model using Langrock et al. (2012)'s hidden Markov model approximation in a frequentist approach. Through extensive simulation experiments and an empirical analysis, we present the statistical evidences validating the efficacy and accuracy of proposed parameterization.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.5
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• pp.693-699
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• 2004

Live animal selection programs that favor animals with a minimum amount of carcass fat are used for improving breeding flocks of sheep. To predict carcass characteristics of live sheep using body measurements in breeding flocks, 200 male and female lambs of two fat-tailed Iranian sheep breeds (Moghani and Makui) were used. Depth of soft tissue over the 12th rib of the live animals was measured with ultrasound (ULGR) and with hypodermic needle (NGR). The height at withers (HW), body length (BL), circumference of heart girth (CH) and width of hooks (WH), were measured. All animals were slaughtered; carcasses were cut into joints and dissected. Breed had a significant effect on all of the live easurements. The Moghani breed showed a higher value for HW, CH, ULGR and NGR, compared to that of Makui. Except for soft tissue depths; ULGR, NGR and GR, the male lambs showed higher values in live and carcass measurements than females. Percentages of carcass, total fat and intermuscular fat in females were higher than that of male lambs. In spite of the higher amount of subcutaneous and intermuscular fat in female (which is usually used for their physiological need, such as pregnancy and lactation), the male lambs had a heavier fat-tail than females. There was a wide range of variation of percentage of total carcass fat and total chemical fat content of carcass in the two breeds. Eventually this wide variation could be use by animal breeders for selection of animals with a lesser amount of carcass fat. Live weight of lambs showed a relatively low correlation with percentage of carcass lean, total fat and subcutaneous and intermuscular fat. Total lean meat was predicted with relatively high coefficients of determination in the two breeds ($R^2$=0.61 and 0.89, respectively). Live weight and carcass traits were predicted using simple measurements, but with $R^2$ ranging from 0.53 to 0.93.

• Asian-Australasian Journal of Animal Sciences
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• v.6 no.1
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• pp.79-86
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• 1993

Twelve docked and 12 intact Najdi lambs of equal numbers of males and females were slaughtered at 40 kg shorn shrunk body weight, Lipid in all empty body fat components; namely, subcutaneous, intermuscular, intramuscular, omental, mesenteric, channel, perirenal, pericardial, tail, viscera, bone and hide, were determined. Except for ram lambs, which had a lower percentage of lipid in intermuscular partition in loin cut, sex did not influence the relative proportion of subcutaneous or intermuscular fat in each wholesale cut. The data also showed that docking did not change the distribution of lipid in intermuscular and intramuscular fat partitions in each wholesale cut. Docked lambs tended to accumulate lower proportions of the lipid in subcutaneous fat component in the cuts located along the dorsal line than intact lambs. The total amount of lipid deposited in the empty body of ewe lamb was heavier in weight than that of ram lamb. Docking had no effect on the distribution of total lipid in the empty body, except for subcutaneous fat component, being greater in docked lambs than did intact ones. Generally, the highest proportion of fat was associated with subcutaneous depot followed, in order, by intermuscular, mesenteric, tail, intramuscular and omental fat partitions.

• Asian-Australasian Journal of Animal Sciences
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• v.6 no.1
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• pp.135-138
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• 1993

Twelve intact and 12 docked Najdi lambs of equal numbers of males and females were utilized in the experiment. All lambs were raised under similar conditions until they attained 40 kg shorn and shrunk body weight. Thereafter, lambs were individually fed ad libitum on a diet formulated to contain 11.20 MJ ME/kg and slaughtered after 60 days feeding period. The results showed that Najdi rams averaged 6.14 kg more total gain (p < .05), required 6.80 kg less feed (p < .05) per kg of gain and produced 3.2 and 3.07 kg more (p < .05) carcass and salable cuts weights over the feeding period than comparable ewes. Body wall thickness and kidney and pelvic fat weight were greater (p < .05) for ewes than for rams; dressing percent, longissimus area and fat thickness were not significantly influenced by sex of lambs. Docked lambs kept for 60 days on feed required 1.80 kg less feed (p < .05) per kg of gain and produced 2.21 kg more (p < .05) salable wholesale cuts weight than intact lambs. Docking was not a significant source of variation for total gain, carcass weight, dressing percent, longissimus dorsi area, body wall thickness and fat thickness.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.9
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• pp.1348-1352
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• 2005

Most breeds of sheep in Iran are adapted to their agro ecological niches where it is likely that they were also artificially selected by their owners. In general, most of sheep breeds are multipurpose producing lambs, wool and milk. To compare the physical and chemical composition of the carcasses of ten Iranian native fat-tailed sheep breeds, 243 male lambs (6-7 months of age) of ten fattailed, Iranian breeds of sheep, Sanjabi (S), Ghezel (G), Afshari (A), Mehrabani (M), Lori (L), Lori Bakhtiari (LB), Kordi Khorasan (K), Sangesari (Sa), Baluchi (B) and Chal (C) were studied. Lamb breed group had a significant (p<0.05) effect on all the carcass traits measured. The LB and C lambs showed the same live weight which was significantly (p<0.05) higher than the other breeds. Carcass dressing- out percentage in S lambs was lowest (p<0.05), but not different from G lambs. K and Sa breeds showed the highest (p<0.05) carcass dressing-out percentage. The S lambs had the highest (p<0.05) lean meat percent. Lean meat percentage was not significantly (p>0.05) different in the G, A, M and C breeds. The Sa and K breeds showed the lowest lean meat percent. The S lambs showed the lowest (p<0.05) fat percent in their carcass, while K and Sa showed the highest (p<0.05). Subcutaneous fat in K, Sa and B was higher (p<0.05) than the other breeds. Lambs of S, G, A and M breeds had the lowest subcutaneous fat in their carcasses (p>0.05). Intramascular fat was significantly (p<0.05) lower in M, S and C despite the fact that this values were highest in B and K lambs. The K and Sa breeds had highest fat-tail percentage (p<0.05) in their carcass, whereas S and G showed lowest. Lambs of G, S and A breeds had higher bone percent than other breeds (p<0.05). Lowest bone percent (p<0.05) was seen in K and Sa lambs. The carcass moisture percent was not significantly (p>0.05) different in S, G, A, M, L and C breeds. M lambs showed the lowest crude protein percentage and S breed the highest (p<0.05). There were no significant (p>0.05) differences among other lamb breeds for this trait. Chemical fat percentage was the same in S, G, A, C and M breeds, but significantly (p<0.05) lower from LB, K, Sa and B. Ash percent in S, G and A had no significant (p>0.05) difference. According to higher lean meat and lower fat percentages in the carcass, the ranking of breeds would be S, G, A, M and C.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.6
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• pp.796-802
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• 2009

The effects of docking on growth traits, fattening performance, carcass characteristics and blood biochemical parameters were investigated using 24 fat-tailed Sanjabi single-born male lambs raised from a large commercial sheep herd. The lambs were randomly divided into two groups. One group (n = 12) were docked at two days of age with rubber-rings using an elastrator. The second group (n = 12) were left intact. After weaning (90 days), all lambs were moved to rustic rangelands for 40 days. Then all the lambs were fed concentrates ad libitum for 60 days during the fattening period. Growth traits, body weight and average daily gain (kg) were recorded at the end of the weaning and fattening periods. Blood biochemical parameters including urea, total protein, glucose, triglycerides, cholesterol, low-density lipoproteins (LDL) and high-density lipoproteins (HDL) were measured during the fattening period. Finally, at the end of the fattening period, eight lambs (4 intact and 4 docked lambs) were slaughtered in order to determine carcass characteristics. Fat-tail docking had no effect (p>0.05) on lamb growth from birth to weaning. Body weight and average daily gain of docked lambs were significantly higher (p<0.05) than for intact lambs at the end of the fattening period. There was no difference in carcass measurements between the two groups, except for chest depth and leg weight which were higher (p<0.05) in docked lambs. During the fattening period, cholesterol and LDL of docked lambs were less than in intact lambs (p<0.05). The current results indicated that docking with rubber rings causes an improvement in growth traits during the fattening period and leads to desirable carcass characteristics compared to intact lambs; interestingly, this procedure had a significant effect on the lowering of blood cholesterol and LDL of docked lambs.

• The Korean Journal of Financial Management
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• v.24 no.3
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• pp.133-152
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• 2007

In this paper, we examine a portfolio selection model in which a safety-first investor maximizes expected return subject to a downside risk constraint. We use the Value-at-Risk as the downside risk measure. We exploit the fact that returns are fat-tailed, and use a semi-parametric method suggested by Jansen, Koedijk and de Vries(2000). We find a more realistic asset allocation than the one suggested by the literature based on the traditional mean-variance framework. For the robustness check, we provide empirical analyses using empirical quantiles. The results highlight that for optimal portfolio selection involving downside risks that are far in the tails of the distribution, our mean-VaR model with a fat-tailed distribution is superior.

• Journal of Animal Science and Technology
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• v.65 no.5
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• pp.922-938
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• 2023

The current study was designed to evaluate the effect of sequential low and high dietary linseed oil (LO; as omega-3 enriched fatty acid; FA) before and post insemination, respectively, on different plasma variables of ewes. Fat-tailed Qezel ewes were assigned randomly to be fed a diet enriched with 3% LO (n = 30) or the saturated FA (SFA; n = 30) three weeks before insemination (Day 0). The lipogenic diet supplemented with 6% LO or SFA was fed after insemination until Day +21. The control ewes were fed an isocaloric and isonitrogenous diet with no additional FA during the study. Estrus was synchronized by inserting a vaginal sponge (Spongavet^®) for 12 days + 500 IU equine chorionic gonadotropin (eCG; Gonaser^®), and ewes were inseminated via laparoscopic approach 56-59 h after eCG injection. The size of ovarian structures was assessed by transvaginal ultrasonography at -21, -14, -2, 0, and +10 days. Blood samples were collected weekly to measure the plasma's different biochemical variables and FA profile. Treatment did not affect the amounts of glucose, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, interleukin-10, interleukin-2, and non-esterified FA (p > 0.05). Conversely, concentrations of triglyceride, cholesterol, tumor necrosis factor-alpha, and insulin-like growth factor-1 were higher in SFA-fed ewes relative to control animals (p < 0.05). LO feeding resulted in greater amounts of n-3 FA isomers in plasma, while higher amounts of stearic acid were detected in SFA fed group 0 and +21 (p < 0.05). The number of ovarian follicles and corpora lutea also were not affected by treatment. Other reproductive variables were not affected by treatment except for the reproductive rate. It seems that LO or SFA feeding of fat-tailed ewes peri-insemination period was not superior to the isocaloric non-additional fat diet provided for the control group during the non-breeding season.