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https://hdl.handle.net/20.500.12428/2760

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Reevaluating the reliability of common multiple comparison tests
(Wiley, 2025) Yiğit, Soner
Many comparison tests are available to determine treatment differences. The validity of these tests is commonly assessed using the Type I error rate. Type I error is obtaining a false positive result. It is known that Fisher's Least Significant Difference (LSD) and Duncan tests have high Type I error rates because even a single false positive is sufficient to constitute a Type I error. For multiple comparison tests, the number of correct decisions (true positives and true negatives) is more important than the Type I error rate. Therefore, in this study, specificity and sensitivity were considered alongside the Type I error rate. Specificity refers to the true negative rate, while sensitivity refers to the true positive rate. A Monte Carlo simulation showed that the LSD and Duncan tests had relatively high Type I error rates; however, when specificity was considered, the LSD and Duncan tests correctly predicted statistically similar groups (true negative) with a mean of 97.00%, while other tests achieved 99.00%. Regarding sensitivity, the LSD and Duncan tests correctly identified statistically different groups (true positive) with a mean of 15.00%, while other tests achieved 3.00%. The true negative rate of the other tests is 1.02 times (99.00/97.00) that of LSD and Duncan. In contrast, the true positive rate of LSD and Duncan is 5.00 times (15.00/3.00) that of the other tests. Therefore, considering both specificity and sensitivity, the LSD and Duncan tests were found to be superior to others. In conclusion, these tests were shown to be more reliable.
A Different Statistical Perspective on the Evaluation of Ecological Data Sets
(Mdpi, 2025) Yiğit, Soner
Statistical significance varies depending on the sample size. Therefore, when the sample size is sufficient, even differences that affect the total variation very little may be statistically significant. For this reason, it is very important to report effect size measures that estimate the share of the difference between groups of samples in the total variation. This study aims to determine the most reliable effect size measures that can be used when evaluating data obtained from ecological studies. The three most popular effect size measures used in practice were compared in terms of their performance in 2700 different experimental conditions. For this purpose, random numbers generated from the multivariate Poisson distribution were used with the Monte Carlo simulation technique. As a result of the simulations, it was determined that Epsilon-squared and Omega-squared were quite unbiased estimators. Therefore, it was concluded that one of these two effect size measures should be reported in addition to the p-value when evaluating ecological studies.
Multidimensional Scaling Analysis of Morphological Spike Traits in Local Wheat Genotypes from the Van Lake Basin
(Mdpi, 2025) Altuner, Fevzi; Jamal-Salih, Sana; Özdemir, Burak; Oral, Erol; Mendeş, Mehmet; Ülker, Mehmet; Najafi, Solmaz
Wheat landraces are considered a valuable resource of potential phenotypic variation that could be used in germplasm improvement. Here, we examined 588 local wheat genotypes collected from farmers' fields at 127 locations around Van Lake Basin and evaluated the morphological diversity and trait associations using Multidimensional Scaling Analysis. Spike and yield traits were measured and scored according to the UPOV and ICARDA phenotypic characterization criteria. Multidimensional Scaling Analysis divided the wheat samples into four main groups based on the number of spikelets (NOS), number of fertile spikelets (NFS), thousand-grain weight (TGW), and number of seeds per spike (NSS) and indicated a strong correlation between NOS and NFS. Furthermore, the analysis revealed that the glume and awn color of most of the genotypes was black, and they were within the locally known Karak & imath;l & ccedil;& imath;k group. Only two genotypes were excluded from the Karak & imath;l & ccedil;& imath;k group; No. 231 was within the Geverik local wheat group, and genotype No. 579 was found to be Tir. The Hevidik and Kirik groups had the same spike color, but the Hevidik group had spikes similar to compactum wheat, whereas the Kirik group had larger spikes. Finally, genotype No. 57 varied from all other genotypes when all the measured traits were taken into consideration. Overall, the Van Lake Basin landraces combine broad similarity with meaningful phenotypic heterogeneity shaped by local environments and traditional on-farm selection. These findings provide practical cues for conservation efforts and for the use of landraces as valuable resources in future wheat breeding programs.
Effect of pasture and feeding systems on hematological traits of ewes and lambs
(Peerj Inc, 2025) Tölü, Cemil; Hanoğlu Oral, Hülya; Alatürk, Fırat; Gökkuş, Ahmet
Context Sustainable livestock production depends on efficient pasture management and the continuous monitoring of the health of grazing animals. Objectives This study investigated the effects of pasture types and sheep production systems on the hematological traits of Karacabey Merino (German Mutton Merino x K & imath;v & imath;rc & imath;k) ewes and lambs grazing on different pasture types throughout the year and reared in a semi-intensive system (control group). Methods In this twenty-six-month study, the hematological characteristics of ewes and lambs grazing on natural pastures and in spring (triticale and oat grass pasture), summer (sorghum Sudangrass and wheat stubble pasture), and autumn (triticale and oat grass pasture) were compared with ewes and lambs reared in a semi-intensive system (no pasture for lambs). A total of 36 ewes (aged 3-4 and 65.2 +/- 0.55 kg) and 98 lambs were used. There were 12 ewes in total in each treatment group and four ewes in subgroups. Each subgroup in the pasture was separated by fences. The 12 ewes tagged in the control group were within the unit sheep flock. Blood samples were taken from the jugular vein of ewes and lambs at three to four-week intervals during live weight weighing using 3-4 mL edged tubes and transported in the cold chain to the laboratory for analysis. Results Pregnant ewes grazing on natural autumn pasture had significantly lower red blood cell (RBC), hemoglobin (HGB), and platelet (PLT) counts (P < 0.05). Animals grazing on wheat stubble pasture exhibited higher hematological values compared to those grazing on Sorghum-Sudangrass pasture (P < 0.05). Lambs in the control group had lower hemoglobin (HGB) and hematocrit (HCT) levels during the post-weaning period than those in the pasture group (P < 0.05). Conclusions The hematological parameters of pregnant Karacabey Merino ewes grazing on natural pastures during the autumn season, as well as those of lambs raised in a semi-intensive system during the post-weaning period, should be carefully monitored. Additionally, appropriate feed supplementation, along with vitamin and mineral support, should be provided to maintain animal health and physiological balance.
Morphological and Morphometric Characterization of an Extremely Short-beaked Turkish Pigeon
(Centenary University, 2025) Erdem, Hakan; Savaş, Türker
This study examines the morphological and morphometric characteristics of the Mısıri pigeon, a unique short-beaked breed from Türkiye. Among Türkiye’s local short-beaked breeds, the Mısıri pigeon stands out with its extremely short beak, cubic head, and prominent eyes. Despite Türkiye’s long pigeon breeding history, limited scientific research has led to inconsistencies in breed classification. Morphological and morphometric traits were recorded in Mısıri pigeons. Analysis of variance and principal component analysis were applied to these traits. The three components explain 73.26% and 81.18% of the variation for head and body traits, respectively. The results showed that male Mısıri pigeons are larger than females, 275.59 g and 243.85 g respectively. However, significant differences were not found between color pattern varieties. Compared to other short-beaked breeds the Mısıri pigeon has the shortest beak ever recorded in Türkiye. Their beak lengths vary between 7.97-12.22 mm. Historical sources suggest that similar pigeons originated in Anatolia and were brought to Europe. However, the Mısıri pigeon’s unique skull structure and short beak distinguish it from related breeds. This study emphasizes the need to document and conserve Türkiye’s local pigeon breeds, which remain underrepresented in scientific registries. Despite their distinct traits, many breeds lack formal recognition due to the absence of studies. Identifying and preserving these genetic resources is crucial for maintaining Türkiye’s rich pigeon heritage. In conclusion, the Mısıri pigeon is a genetically and morphologically significant breed. Its documentation contributes to the conservation of Türkiye’s local breeds and the continuation of the country’s historical pigeon breeding culture.
Post-Feeding Behaviors of Newborn and Peak Lactation Dairy Cows
(Kahramanmaraş Sütçü İmam Üniversitesi, 2025) Tölü, Cemil; Durmuş, Kader
This study compared the behavioral characteristics of newborn and peak lactation dairy cows in the barn after feeding. The study used 10 newborn and 10 peak lactation Holstein cows. Behavior was directly observed for 10 consecutive days between 11:00-13:00 at five-minute intervals using the time sampling method. After the morning feeding, eating, lying down, locomotion, lying, and standing rumination, friendly interaction, and abnormal stereotypic behavior of newborn and peak dairy cattle were significantly different (P <= 0.05). Cows in the peak period (33.7%) showed more feeding behavior than cows in the neonatal period (12.4%) (P=0.0001). Lying behavior was 21.9% in the neonatal group and 15.7% in the peak group (P=0.0561). Locomotion behavior was 12.3% in the neonatal group and 17.1% in the peak group (P=0.0028). Lying rumination was 19.8% in the newborn group and 8.7% in the peak group (P=0.0022). Standing rumination was significantly different in the neonate (8.2%) and peak (1.2%) groups (P=0.0008). In conclusion, it was observed that the transition and peak periods in dairy cattle caused differences in the behavioral characteristics of the animals. It can be said that the difference in feeding visits and activities due to the continuity of feeding behavior and the difference in the ratio of roughage in the daily rations is the most important source of behavioral differences between the groups, in which different physiological and metabolic reactions occur.
Effects of Forage-to-Concentrate Ratio on Abnormal Stereotypic Behavior in Lambs and Goat Kids
(MDPI, 2025) Tölü, Cemil
A crucial component of small ruminant production, particularly where intensive systems are becoming more prevalent, is determining the forage-to-concentrate (F:C) ratio in their daily diets. The effects of the F:C ratio in lambs and goat kids' daily diets on growth, stereotypical behavior, and blood biochemical parameters were investigated. Eighteen Tahirova sheep lambs and 18 Turkish Saanen goat kids were used, divided into three groups using the following F:C ratios: 20:80, 60:40, and 80:20. Growth rates, weight gains, and feed conversion ratios were determined. Urea nitrogen, glucose, non-esterified fatty acids, creatine kinase, and cortisol hormones were measured in blood samples. In lambs, growth remained consistent across F:C groups. In goat kids, however, the 20:80 group showed superior growth and weight gain. Based on the F:C ratios, behavioral differences were found in forage feeding, rumination, water consumption, and standing activities. Similarly, the 20:80 group displayed higher rates of bar biting, crib biting, and wool biting in lambs, as well as bar biting, crib biting, bucket biting, and chain chewing in goat kids. Cortisol levels were significantly higher in the 80:20 group than in the 20:80 group for both species. Insufficient forage can cause abnormal stereotypical behaviors, which negatively impact animal welfare.
Effect of Melatonin Treatment on Reproductive Hormones and Sexual Behaviors in Sheep
(Namik Kemal University - Agricultural Faculty, 2025) Öztürk, Nesrin; Tölü, Cemil
In seasonal oestrus animals such as sheep, out-off-season lambing practices and synchronization of oestrus are important in terms of herd management and farm economics. The present study aimed to determine the effects of melatonin implants administered before the breeding season on melatonin, estrogen, progesterone hormone concentrations, and sexual behavior in Tahirova sheep. The study was conducted on 60 Tahirova dairy ewes, aged 1-4 years, and 6 head rams, aged 1-2 years. On June 26, melatonin implants were administered to half of the ewes (18 mg dose/ewe) and rams (54 mg dose/ram). Fifteen days after the implantation of melatonin, all the ewes (530 g/ewe) and rams (660 g/ram) were given supplemental feeding (flushing) with grain feed for a period of 60 days. On August 1, the ewes exhibiting signs of estrus following the introduction of a ram were relocated to individual paddocks, where mating was conducted using the hand-mating method. The frequency of sniffing, touching the ram's scrotum, turning the ram, head-turning, and tail wagging was recorded during the hand-mating procedure. Additionally, the sexual behaviors exhibited by the ram were documented. Furthermore, an investigation was conducted to ascertain whether an interaction occurred within the first minute. The intervals, sexual interaction rate of the ewe, total frequency of sexual interaction, time per sexual interaction, and total sexual interaction time were observed. Blood samples were collected regularly on the initial day, the 21st day, the 42nd day, the 63rd day, the 94th day, and the 129th day for subsequent hormone analysis. Hormonal analyses were conducted using the ELISA method on blood serum samples. The melatonin hormone concentration was observed to be higher in the treatment (MT) group than in the control (C) group on the 63rd day (P=0.0476). The sexual interaction rate of the MT group was found to increase significantly in comparison to the C group (P=0.0045). Additionally, the gestation rate was shorter in the MT group than in the C group (P≤0.05). It can thus be concluded that the melatonin implant, when applied before the breeding season, significantly increases melatonin hormone concentrations on the 63rd day and significantly shortens the periods of gestation in Tahirova dairy sheep. © Bu çalışma Tekirdağ Namık Kemal Üniversitesi.
Effect of Glycyrrhiza glabra L. on Broiler Growth Performance, Slaughter and Carcass Characteristics, Blood biochemistry, and Hematological Parameters: A Systematic Review
(Sciendo, 2025) Esen, Selim; Prete, Andrea; Centoducati, Gerardo; Lackner, Maximilian; Palangi, Valiollah; Tölü, Cemil
In this systematic review, 79 research articles focusing on the impact of Glycyrrhiza glabra L. (licorice) supplementation in broilers were meticulously examined, assessing growth performance, slaughter and carcass traits, and blood parameters. Out of these, 12 studies met the predefined criteria. Licorice supplementation, particularly in the absence of specific dietary constraints, signifi-cantly improved feed consumption, body weight gain, and feed conversion efficiency in broilers. The addition of licorice influ-enced slaughter and carcass traits, increasing the dressing percentage, although results varied based on dosage and form of supplementation. Effects on abdominal fat and spleen weights were inconsistent, while liver, heart, and gizzard weights gen-erally increased. Licorice supplementation affected blood biochemistry, showing varied impacts on markers like glucose, cho-lesterol, and triglycerides. Notably, licorice exhibited potential antioxidant properties by reducing malondialdehyde levels, in-dicating decreased oxidative stress. The review highlighted diverse outcomes across growth performance, slaughter traits, car-cass parameters, and blood biochemistry due to licorice supplementation. Variability in dosage, form, and administration methods underscored the need for standardized protocols. Future research should concentrate on uncovering underlying mechanisms, expanding geographical diversity, and exploring interactions with other feed additives, especially in antibiotic-free diets. Despite its promise, further investigation is necessary to optimize licorice's role in poultry production. © 2025 Selim Esen et al., published by Sciendo.
Relations Between the Great War and Wheat Prices: An Analysis from the Ottoman Empire Perspective
(Emerald Group Publishing Ltd., 2021) Tufan, Ekrem; Savaş, Türker; Atabay, Mithat
Introduction: It is commonly observed that the ratio of food prices during the war times had become significantly more important than usual periods within the countries including Turkey, known as the Ottoman Empire that previously defeated in Balkans just before the Great World War. The scope of the study is to analyze increased or decreased wheat prices together with price fluctuations during the war period. Aim: This study investigates the food pricing progress during The Great World War and its relationship with wheat prices. Method: A model for the behavior of time series is applied to compare the important days of the war data against the timeline of wheat prices for British, German, and French. The statistical test named Holt-Winters uses exponential smoothing technique to encode the various values from the past and predicts “typical” values for the present and the future. Findings: As a result, it can be said that wheat prices had anomaly patterns during the specific dates in war for French, British, and German sides. Great Britain’s wheat prices increased significantly on April 1915 when landings began on the Gallipoli Peninsula. Wheat prices in Great Britain and Germany dropped significantly just before on July 1916 when the first Battle of the Somme began. However, it increased in Great Britain whilst decreased considerably in Germany in March 1918 when the Soviet Government signed a separate peace agreement with the Central Powers. A significant increase for France was observed only at the end of this war.
Multiple Linear Regression versus Automatic Linear Modelling
(Arquivo Brasileiro Medicina Veterinaria Zootecnia, 2024) Genç, S.; Mendeş, Mehmet
In this study, performances of Multiple Linear Regression and Automatic Linear Modelling are compared for different sample sizes and number of predictors. A comprehensive Monte Carlo simulation study was carried out for this purpose. Random numbers generated from multivariate normal distribution by using RNMVN function of IMSL library of Microsoft FORTRAN Developer Studio composed the material of this study. Results of the simulation study showed that the sample size and the number of predictors are the main factors that lead to produce different results. Although both methods gave very similar results especially when studied with large sample sizes (n >= 100), the Automatic linear modelling is preferred for analyzing data sets due to its simplicity in analyzing data and interpreting the results, ability to present results visually and providing more detailed information especially studying large complex data sets. It will be beneficial to use the Automatic linear modelling especially in analyzing massive and complex data sets for the purposes of investigating the relationships between one continuous dependent and 10 or more predictors and determine the factors that affect the response or target variable. At the same time, it will also be possible to evaluate the effect of each predictor with a more detailed response.
The domestic livestock resources of Turkey: inventory of pigeon groups and breeds with notes on breeder organizations
(Cambridge Univ Press, 2013) Yılmaz, O.; Savaş, Türker; Ertuğrul, M.; Wilson, R. T.
The pigeon is one species among the numerous domestic animal types that contribute to the economy of Turkey as food and work, and provide diversion and pleasure for the nation's people. Pigeons are kept at the household level, usually in small numbers, by many hundreds of thousands of Turkish families, yet they have been subject to little study. This paper collates much of the information available (almost all in the Turkish language) to provide a brief history of the bird in Turkey. An inventory of the nine groups and 72 breeds that have been identified is presented. Some of these breeds are international in status, some are widespread in Turkey and some have only local distribution; many breeds have synonyms which are used in their areas of distribution. There is little government or academic support for pigeon breeders. The private Pigeon Breeders Association of Turkey and the Turkish Pigeon Federation are umbrella organisations for a number of breed clubs. In an initial attempt to standardise the national pigeon genetic resources, two of the more widespread breeds have been registered with the Animal Breeds Registration Committee of the Ministry of Food, Agriculture and Livestock.
Characterization of aroma-active compounds, sensory properties, and proteolysis in Ezine cheese
(Elsevier Science Inc, 2009) Karagül Yüceer, Yonca; Tuncel, Barış; Güneşer, Onur; Engin, Burcu; İşleten, Müge; Yaşar, Kurban; Mendeş, Mehmet
Ezine cheese is a white pickled cheese ripened in tin-plate containers for at least 8 mo. A mixture of milk from goat, sheep, and cow is used to make Ezine cheese. Ezine cheese has geographical indication status. The purposes of this study were to determine and compare the changes in basic composition, aroma, and sensory characteristics, and proteolytic activity of Ezine cheese stored in tinplate containers and plastic vacuum packages during storage. Aroma-active compounds were determined by thermal desorption gas chromatography olfactometry. To evaluate the proteolytic activity, casein and nitrogen fractions were determined. The results indicated that compounds identified at high intensities were dimethyl sulfide, ethyl butyrate, hexanal, ethyl pentanoate, (Z)-4-heptenal, 1-octen-3-one, acetic acid, butyric acid, and p-cresol. Characteristic descriptive terms were cooked, whey, creamy, animal-like, sour, and salty. The level of proteolysis increased in Ezine cheese during storage. Ezine cheese can be ripened in small-size packaging after 3 mo of storage. Approximately 6 mo is sufficient to produce the characteristic properties of Ezine cheese.
Apical sodium-glucose co-transport can be regulated by blood-borne glucose in the ruminal epithelium of sheep (Ovis aries, Merino breed)
(Cambridge Univ Press, 2004) Ataşoğlu, Cengiz; Gäbel, G.; Aschenbach, J. R.
The intestinal Na-dependent d-glucose co-transporter (SGLT)-1 in sheep is under dietary regulation by luminal substrates. The aim of the present study was to find out whether the SGLT-1 in the forestomach of sheep is also regulated by sugars. Furthermore, the location of a possible glucosensor (luminal v. intracellular v. basolateral) was to be elucidated. Ruminal epithelia of sheep (Ovis aries, Merino breed) were pre-incubated in Ussing chambers with various substrates on the mucosal (i.e. luminal) or serosal (i.e. blood) side. This pre-incubation period was followed by a second pre-incubation period without the tested substrates (washout period). Thereafter, apical d-glucose uptake by ruminal epithelial cells was determined with 200 mumol d-[C-14]glucose/l in the absence or co-presence of the SGLT-1 inhibitor, phlorizin. Pre-incubation with d-glucose on the mucosal side had no significant effect on apical d-glucose uptake (P>0.05). In contrast, pre-incubation with d-glucose, d-mannose, 3-O-methyl-d-glucose or sucrose on the serosal side significantly increased d-glucose uptake compared with mannitol-treated controls (P<0.05). Serosal pre-incubation with cellobiose or d-xylose had no effect. The stimulation of d-glucose uptake by serosal d-glucose pre-incubation was concentration dependent, with maximal stimulation at about 10 mmol/l. We conclude that the ruminal SGLT-1 can be up-regulated in a concentration-dependent manner by blood-borne d-glucose via an extracellular sugar-sensing mechanism.
Study on Milkability Traits in Brown Swiss Cows Reared Eastern Region of Turkey
(Medwell Online, 2008) Aydın, Recep; Yanar, Mete; Güler, Olcay; Yüksel, Sadrettin; Uğur, Feyzi; Turgut, Leyla
The study was carried out to determine the effect of environmental factors on milkability traits and to estimate genetic parameters and relationships among milk yields, milk flow rate (MFR) and milking time (MT) of Brown Swiss cows reared in Eastern Region of Turkey. The data used in this study consisted of 2051 observations of milking time and milking flow rate on 315 lactations of 163 cows. The averages for MFR, MT and total test day milk yield (TTDMY) were 0.972 kg min(-1), 5.46 min and 11.35 kg, respectively. Stage of lactation and parity had significant (p<0.01) effect on the MFR, MT and TTDMY. Multiparous cows had higher MT and TTDMY (p<0.01) than primiparous cows. Calving season only significantly (p<0.01) affected on TTDMY. The heritability estimates for MFR, MT and TTDMY were 0.37, 0.37 and 0.21, respectively. The positive genetic correlations of MFR with actual milk yield, 305 days milk yield, TTDMY were 0.423, 0.585 and 0.735, respectively, while negative genetic correlations between MT and milk yield traits were calculated. The higher heritability values for MFR and MT suggested that selection of a good milkability seems to be promising and genetic improvement in MFR and MT might be achieved through selection for milk production.
Effects of whole and steam-flaked corn supplementation on productive performance, serum parameters, and reproductive characteristics of dairy ewes
(Copernicus Gesellschaft Mbh, 2024) Akbağ, Hande Işıl; Tölü, Cemil; Savaş, Türker; Konyalı, Aynur; Coşkun, Baver; Yurtman, İsmail Yaman
This study aimed to determine the effects of whole and steam-flaked corn supplementation on the feed intake, serum parameters, and reproductive performance of dairy ewes. A total of 48 ewes (at the end of their lactation period; 57 +/- 1.3 kg body weight, BW; 2.69 +/- 0.19 body condition score, BCS) were divided into three treatment groups (16 animals per group): the control group (C), which was fed with alfalfa hay and corn silage; the whole-corn group (WC), which was fed with alfalfa hay, corn silage, and whole corn; and the steam-flaked corn group (FC), which was fed with alfalfa hay, corn silage, and steam-flaked corn. The study was conducted for 15 d before ram introduction and for 30 d during the mating in the breeding season. The WC group had higher dry matter (DM), metabolizable energy (ME), and starch intake values than the FC group (P<0.0001). The BW and BCS values were increased in the groups supplemented with whole corn and steam-flaked corn (P <= 0.05). The lambing rate was higher in ewes from the WC and FC groups (P <= 0.05). Whole and steam-flaked corn supplementation did not affect the non-return ratio or litter size (P>0.05). The serum glucose concentration was similar among the groups, whereas the serum urea concentration increased with either whole or steam-flaked corn supplementation (P <= 0.05). In conclusion, whole and steam-flaked corn supplementation increased the BW, BCS, and lambing rate values in dairy ewes.
Genetic diversity and population structure of Anatolian Hair goats, an ancient breed
(Copernicus Gesellschaft Mbh, 2024) Demiray, Aylin; Gündüz, Zuhal; Ata, Nezih; Yılmaz, Onur; Cemal, İbrahim; Konyalı, Aynur; Semen, Zeynep
This study aimed to investigate the genetic characterization and diversity of Hair goats from 10 regions using 20 microsatellite markers. A total of 522 alleles were observed. The INRA0023 locus exhibited the greatest number of alleles (48), while the DRBP1 locus had the highest effective allele number (16.27), and the BM1818 and DRBP1 loci had the highest polymorphic information content value (0.94). The expected heterozygosity value ranged from 0.85 (ILSTS011) to 0.94 (BM1818, SRCRSP15, and DRBP1). The Hair goat populations in Konya and Hatay displayed the lowest and highest allele numbers, with values of 10.40 and 16.25, respectively. The fixation index (FIS) values are significant in defining population structures and determining the extent of heterozygosity losses. The FIS values exhibited a range of 0.031 in Mu.gla to 0.226 in Burdur. A total of 107 unique alleles were identified in Hair goat populations. However, it is noteworthy that, out of all the alleles, only 25 had a frequency exceeding 5 %. The results indicate that the microsatellite markers utilized demonstrate sufficient levels of polymorphism, making them appropriate for efficiently investigating the genetic variability of Hair goat populations.
Use of a deletion approach to assess the amino acid requirements for optimum fermentation by mixed micro-organisms from the sheep rumen
(Cambridge Univ Press, 2003) Ataşoğlu, Cengiz; Guliye, A.Y.; Wallace, R.J.
Amino acids stimulate the growth rate and growth yield of ruminal micro-organisms, but the basis of this stimulation, in terms of amino acids which most limit growth, has never been fully established. Here, for the first time, a deletion approach was investigated using in vitro incubations of mixed ruminal micro-organisms supplied with a mixture of xylose, starch and cellobiose as energy sources and ammonia plus a complete amino acids mixture or mixtures with a single amino acid omitted as nitrogen sources, enabling the evaluation of the impact on ruminal fermentation of the deletion of a single amino acid from a complete amino acids mixture. Significant effects (P<0.05) on total gas production were observed after 10 h of incubation when glutamate, glutamine, isoleucine, leucine, phenylalanine, serine, tryptophan or tyrosine were deleted from the amino acids mixture. The only significant effect of an amino acid deletion on volatile fatty acid production at 10 h was with serine (P<0.05), although the effect of omitting others, including arginine, isoleucine, leucine and phenylalanine, approached significance (P<0.01). The removal of leucine caused a 0.09 decrease in growth yield (P<0.05); no other deletion affected the yield significantly (P>0.05). Net gas production for each treatment was calculated by subtracting gas production in the absence of carbohydrates from gas production in their presence, thus eliminating gas production from amino acids from the values. At all times up to 10 h, the most significant effects on net gas production were found when serine, leucine, or the aromatic amino acids were omitted from the amino acids mixture. Thus, the deletion approach confirmed that no single amino acid limits ruminal fermentation more than any other, although a few, principally phenylalanine, leucine and serine, have a particularly significant role in the ruminal fermentation rate of soluble, rapidly degraded materials and/or microbial growth efficiency.
Behaviour of sheep freely grazed on Gokceada Island (Turkey) rangeland reclaimed by different methods
(Cambridge Univ Press, 2017) Tölü, Cemil; Alatürk, Fırat; Özaslan Parlak, Altıngül; Gökkuş, Ahmet
Extensive sheep and goat farming is common in the rangelands of Gokceada Island, NW Turkey. The aim of the current study was to investigate the behaviour of indigenous Gokceada sheep over these rangelands and factors influencing their behavioural characteristics. Grubbing (with chisel ploughing to a depth of 20 cm), burning (the entire top part of plants) and cutting (10-15 cm stalk on the surface of the soil) were carried out on selected rangeland to reduce prickly burnet (Sarcopoterium spinosum (L.) Spach) from the vegetative covering, then forage crop seeds were sown to improve plant cover. Forty head of Gokceada-bred sheep were placed in eight fenced plots (half seeded, half unseeded) on reclaimed and natural rangeland for 2 years. Sheep behaviour was observed for a period of 1 year. Each plot was arranged with a stocking rate of 267 sheep/ha and contained five sheep that grazed freely within each plot. Sheep behaviour was observed diurnally through direct observation by time sampling (10 min) and continuous sampling methods. During the period of 1 year, the observed sheep spent an average of 053 of their time grazing in daylight, 030 of their time in rangelands on other activities and 017 in the paddocks. Significant differences were observed in the time of grazing, resting, locomotion and rumination by season. The highest grazing ratio was noticed in spring while the lowest was in summer. Sheep exhibited walking behaviour 106 times/day. The sheep mostly (066) grazed on prickly burnet throughout the year although, when available, they tended to prefer herbaceous plants. The behaviour of sheep in the two natural (unreclaimed) plots was significantly different from those placed in other plots, mainly due to the mass of prickly burnet shrub found in the natural plots.
Carcass Characteristics and Meat Quality of Karacabey Merino lambs Reared under Triticale and Oat Pastures Compared with Stall-Fed Lambs
(Mdpi, 2023) Hanoğlu Oral, Hülya; Kecici, Pembe Dilara; Alatürk, Fırat; Tölü, Cemil; Ekiz, Bülent; Gökkuş, Ahmet
Simple Summary An economical livestock production model in which all the needs of the lambs can be met and they reach the optimal slaughter weight in the shortest possible time is the primary goal of all production models. Since the production system is an important factor for carcass and meat quality, different production systems have been developed. In intensive systems with concentrates, carcasses tend to be fatter and reach optimal slaughter weight faster, whereas pasture-fed animals have a better fatty acid profile and redder colour due to higher physical activity. In our study, we investigated the effects of feeding system, birth type, gender, and birth year on the carcass and meat quality of Karacabey Merino lambs. The effects of gender and birth type on Karacabey Merino lambs showed the expected results: single-borns have more muscle tissue than multiples, males have more muscle tissue than females, and females have higher carcass fatness. In conclusion, a pasture-based feeding system is more suitable for Karacabey Merino lambs than a stall feeding system, if lean and tender meat is preferred. However, it should not be ignored that lambs fed in stalls showed better fattening performance in terms of conformation and fatness, during the same period.Abstract Fifty-eight Karacabey Merino lambs were used to study the effects of feeding system (triticale pasture, oat pasture, or stall-fed), birth type (single or multiple), gender (male or female), and birth year (2016 or 2017) on various carcass and meat quality characteristics. Stall lambs had higher conformation (CS) and fatness (FS) scores, and higher meat L* and h* values than the two pasture groups, possibly due to higher fat content, while oat pasture lambs had the most tender meat. Single-born lambs had higher CS, FS, and Longissimus thoracis muscle section area, while females had higher subcutaneous and non-carcass fat deposits than their counterparts. Both single-born lambs and 2016-born lambs had higher meat a* and C* values than their counterparts. In conclusion, a pasture-based feeding system is more suitable for Karacabey Merino lambs than a stall feeding system, if lean meat and/or meat products are preferred. However, it should not be ignored that stall-fed lambs showed a better fattening performance in terms of conformation and fatness, during the same period.

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