Ayhan Yılmaz - Academia.edu (original) (raw)

Papers by Ayhan Yılmaz

Anadolu tarım bilimleri dergisi, Feb 27, 2008

The aim of this study was to detect variations in several sexual behaviors of Norduz ram lambs ba... more The aim of this study was to detect variations in several sexual behaviors of Norduz ram lambs based on age. A total of 32 approximately six-month-old Norduz ram lambs were subject to 13 sexual behavior tests performed at 14-day intervals and an additional test performed one month after the last biweekly test, 14 tests a total. Tests consisted of individually exposing lamb rams to 1-3 estrus ewes (stimulus female) for 15-minute periods. The basic statistics for the lip curl response, the anogenital sniffing, the raising of tail, the vocalization, the mount frequency (number of mounts) and the least square mean for mount duration were found to be 1.15±0.07, 4.41±0.18, 0.76±0.07, 8.08±0.44, 10.79±0.52 and 1.34±0.12 minutes, respectively. Findings indicated irregular variations in sexual behaviors of Norduz ram lambs based on age.

Agriculture

The aims of our study were to evaluate the associations between calving difficulty and lameness a... more The aims of our study were to evaluate the associations between calving difficulty and lameness and their effects on milk yield and quality traits. A total of 4723 calving cases were evaluated for calving difficulty using a 4-point scoring system. Lameness was diagnosed with a visual locomotion score system from 1 to 30 days after calving in 333 fresh dairy cows. Cows were divided into non-lame cows and lame cows. Milk quality traits were registered using Lely Astronaut® A3 milking robots. The normal distribution of all indicators was assessed using the Shapiro–Wilk normality test. Normally distributed milk indicators were expressed as mean ± standard error of the mean. Differences between the mean values of their groups were determined using the Fisher’s least significant difference test. We categorized cows by health status, i.e., lame (LA) and non-lame (HL) cows, and according to calving difficulty (CD) (on a 4-point scale: 1—no problem, 2—slight problem, 3—problems requiring ass...

Animals, 2022

Hyperketonemia is a very common metabolic state in dairy cows, which result in lower milk product... more Hyperketonemia is a very common metabolic state in dairy cows, which result in lower milk production, impaired fertility, and increased frequency of other diseases. In this study, we aimed to determine the influence of season, parity, and milk yield of cows on beta-hydroxybutyrate (BHB) concentration in the second week of lactation (WK 2) and establish the relationship between BHB concentration in WK 2 and reproduction performance traits such as insemination rate and first insemination day of Lithuanian Black and White dairy cows. The study included clinically healthy Lithuanian Black and White cows (n = 692). Blood BHB concentration was measured using capillary blood samples collected after morning milking when cows were 7–10 DIM. The impact of WK 2 blood BHB concentration on the insemination rate and first insemination day were investigated. The effect of BHB was evaluated according to the season, parity, and milk yield per lactation (305 DIM). Significant differences were observe...

Selcuk Journal of Agricultural and Food Sciences, 2018

The aims of this study were to evaluate the economic losses caused by infertility in Holstein cro... more The aims of this study were to evaluate the economic losses caused by infertility in Holstein crossbreed dairy cows raised in a cattle farm in Kırşehir province. Data recorded from 294 Holstein crossbreed dairy cows between 2009-2017 were used in this study. A total of 1077 lactation records from these cows were used as study material. Age at first service (AFS), age at first calving (AFC), calving interval (CI) and number of inseminations per pregnancy (PI) parameters were evaluated. The values of AFS, AFC, CI, and PI were 491.83 days, 766.86 days, 432 days and 2.64, respectively. There were 41.83 days, 36.86 days, 67 days and 0.99 of difference from ideal reproduction values. When calculating economic losses, all detail was provided from farm zootechnician and veterinarian. The difference between the AFS and AFC (4.97 days) caused 16.189.9 TL economic cost. Economic costs of the AFC, CI, andPI were 450 162.3 TL, 1 307 852.7 TL, and 135 729 TL, respectively. As a result, it was understood that this farm had significant deviations from ideal values for fertility traits between 2009-2017 and these deviations caused 581.41 TL daily, and 1 909 933.9 TL total cost.

Bu derleme Dogu Anadolu Bolgesi koyunculugunun genel uretim yapisi bakimindan organik tarim uygul... more Bu derleme Dogu Anadolu Bolgesi koyunculugunun genel uretim yapisi bakimindan organik tarim uygulamalarina elverisliligini degerlendirmeyi hedeflemektedir. Boylece, koyunculuk bakimindan soz konusu bolgede devam eden geleneksel uretim sistemlerinin organik koyunculuk acisindan ozellikleri ortaya konulmaktadir. Sonuc olarak Dogu Anadolu Bolgesi genelde organik hayvancilik ozelde ise organik koyunculuk bakimlarindan degerlendirilmesi noktasinda onemli bir potansiyel tasimaktadir.

Selcuk Journal of Agricultural and Food Sciences, 2020

Heat stress is an environmental factor that negatively affects the morphological and physiologica... more Heat stress is an environmental factor that negatively affects the morphological and physiological properties of dairy cattle. The aim of this study is to investigate the relationship between heat stress and milk yield, milk fat ratio and body temperature in Holstein-Friesian dairy cattle. The data of the study was obtained from a private Kurtalan Farm of Siirt province, the Southeastern Anatolia Region of Turkey. Milk yield and other traits of 13 head Holstein-Friesian dairy cattle were recorded in March, April, May, June, July, August and September. In addition, temperature and humidity records were recorded in the farm and in the parlor to be used for calculating the temperature humidity index value. In the analysis of data, correlation and regression methods were used. As a result of the study, the negative correlation (P<0.01) was found between milk yield and milk fat ratio and the positive correlation (P<0.001) were detected between heat stress and body temperature. In addition, a significant negative relationship was observed between rectal temperature and milk yield (P<0.01).

South African Journal of Animal Science, 1970

This study was conducted to determine the effects of the addition of micronized zeolite (MZ) on t... more This study was conducted to determine the effects of the addition of micronized zeolite (MZ) on the fattening performance, blood parameters, faecal ash and nitrogen levels of lambs fed concentrate feeds intensively. For two months 25 four-month-old Merino x Ile de France crossbred male lambs (21.1 ± 1.32 kg live weight) were fed 100 g alfalfa hay and a mixed concentrate diet containing 0%, 1%, 2% or 3% additional MZ. At the end of the study, bodyweight gain and feed consumption were not affected by the treatments. Similarly, the addition of up to 2% MZ to the diet did not affect slaughter weight, hot carcass or cold carcass weights, but they decreased at 3% MZ inclusion. No differences were observed between the groups in terms of blood urea nitrogen, plasma glucose, serum creatinine, triglyceride, sodium, potassium and chlorine concentration. However, serum total protein, calcium and phosphorus concentrations were affected by MZ supplementation. The addition of MZ to the ration did ...

Indian Journal of Animal Research, 2018

he aims were to identify the body weight of the several age groups in Norduz lambs and its correl... more he aims were to identify the body weight of the several age groups in Norduz lambs and its correlations between these traits were to determine the best non-linear growth curve models for the growth performance of the Norduz sheep breed. A total of 91 male and female of Norduz lambs were evaluated under extensive system conditions. The least square means for weights at birth and at 15, 30, 45, 60, 75, 90, 105, 120, 135, 150, 165, 180, 195 and 210 days of age periods were 4.51±0.56, 9.28±0.25, 11.14±0.29, 14.99±0.37, 18.21±0.43, 22.54±0.54, 22.33±0.25, 23.59±0.54, 25.58±0.55, 28.07±0.58, 29.45±0.60, 29.98±0.84, 32.44±0.61, 32.03±0.59 and 31.45±0.57 kg, respectively. There were differences in favor of lambs of four-year old dams at 15 days of age and also lambs born single at 90 days of age for the body weight. The effect of weight of dam at birth, 30, 45, 60 days of age was significant (P less than 0.05-P less than 0.01) and the birth weight in lambs importantly effected the weights a...

Türkiye Tarımsal Araştırmalar Dergisi, 2019

Bu çalışmada, dünyada ve Türkiye’de manda yetiştiriciliğinin çeşitli göstergeler bakımından değer... more Bu çalışmada, dünyada ve Türkiye’de manda yetiştiriciliğinin çeşitli göstergeler bakımından değerlendirilmesi ve geleceğine ilişkin bazı öngörülerde bulunulması amaçlanmıştır. Son yıllarda organik hayvansal üretime yönelik eğilimler hâlihazırda geleneksel üretim yapılarını koruyan hayvancılık kollarını yeniden önemli kılmaktadır. Manda yetiştiriciliğinin de, hayvancılıktaki yeni eğilimler dikkate alındığında, oldukça önemli bir hayvancılık kolu olup bu yöndeki taleplerin karşılanmasına katkı sunması beklenmektedir. Dünyada ve Türkiye’de manda yetiştiriciliğinin çoğunlukla geleneksel üretim sistemlerinin devam ettirildiği Asya kıtasında varlık göstermesi dönüştürülme ihtiyacını gerektirmektedir. Nitekim bazı Avrupa ülkelerinde manda yetiştiriciliğinde daha modern yaklaşımların benimsenmeye başlandığı gözlenmekte ve bu yetiştirme kolunun endüstriyel boyutlarının güçlendirilmeye çalışıldığı anlaşılmaktadır. Türkiye’de ise manda yetiştiriciliği, son yıllara kadar başta manda varlığında...

Kahramanmaraş Sütçü İmam Üniversitesi Tarım ve Doğa Dergisi, 2020

Bu çalışma Bitlis ili Güroymak ve Mutki ilçelerinde faaliyet gösteren yetiştiricilerin manda besl... more Bu çalışma Bitlis ili Güroymak ve Mutki ilçelerinde faaliyet gösteren yetiştiricilerin manda besleme, manda ürünlerinin üretimi ve pazarlanması, sağlık koruma ve desteklemelere ilişkin görüşlerini belirlemek için yapılmıştır. Araştırmanın materyalini Bitlis ilinde manda yetiştiriciliği yapan ve basit tesadüfi örnekleme yöntemiyle belirlenen toplam 136 manda yetiştiricisine uygulanan anketlerden elde edilen veriler oluşturmuştur. Elde edilen veriler SAS paket programında analiz edilmiştir. Araştırmada Bitlis ilinde manda yetiştiriciliğinin temelde orta yaş grubu (40-50 yaş) veya daha büyük yaş (51 yaş ve üstü) grubundaki yetiştiriciler tarafından gerçekleştirildiği, yetiştiricilerin yetersiz arazi varlığına bağlı olarak (0-20da/işletme) kendi yemlerini üretemedikleri ve meraların yetersiz kaldığı gözlenmiştir. Manda sütünden temelde yoğurt ve peynir üretimi için faydalanıldığı, manda ürünlerinin pazarlanması konusunda bir planlarının olmadığı ve ürettikleri ürünlerde fiyat düşüklüğü ...

Türk Tarım ve Doğa Bilimleri Dergisi, 2019

Kırmızı et tüketimi insanların sağlıklı beslenmesinde ve ülkelerin gelişmişlik düzeyinin belirlen... more Kırmızı et tüketimi insanların sağlıklı beslenmesinde ve ülkelerin gelişmişlik düzeyinin belirlenmesinde önemli bir faktördür. Bu çalışma Siirt ili Merkez ilçede kırmızı et tüketim alışkanlığını ve tüketimi etkileyen faktörleri incelemek amacıyla yapılmıştır. Veriler tesadüfi örnekleme metoduyla belirlenen 161 kişi ile yüzyüze anket yapılarak elde edilmiştir. Deneklerin yaklaşık olarak yarısı kadınlardan oluşmakta ve çoğunluğu Siirt ilinde sadece ikamet ettiklerini belirtmiştir. Araştırmaya katılanların çoğunluğu lise-lisans derecesine sahip, evli ve orta yaşlı insanlardan oluşmaktadır. Katılımcılar genellikle koyun etini, orta fiyatlı etleri ve alım yeri olarak da kasabı tercih etmektedirler. Katılımcıların kırmızı eti tercih etmesinde alışkanlık başta olmak üzere lezzetli ve sağlıklı olması gibi faktörler de etkili olmuştur. Tüketiciler kırmızı et satın alırken alım yerinin hijyenik olmasına ve ürünlerin etiketli olmasına daha çok dikkat etmişlerdir. Tüketicilerin et tüketim mikta...

Archives Animal Breeding, 2012

The objective of this study was to investigate the possibility of increasing ovulation rate in No... more The objective of this study was to investigate the possibility of increasing ovulation rate in Norduz sheep by immunization against inhibin-based peptide immunogens. A total of 18 primiparious Norduz ewes were used for this experiment. Eight ewes have received two times inhibin α-subunit 1-32 porcine vaccine with 3 weeks interval. The rest was kept as control. Antibody binding test by standard ELISA method did not provide reliable information. However, ultrasonographic inspection showed that significantly high number of follicle with 5 mm and larger diameter (P<0.01) has developed in immunized ewes. Moreover, 3 of immunized ewes have lambed twin. However, twin birth was not observed in control group.

Ankara Üniversitesi Veteriner Fakültesi Dergisi, 2019

The object of this study was to assay different levels of teat hyperkeratosis and to determine th... more The object of this study was to assay different levels of teat hyperkeratosis and to determine the connections between teat thermographic characteristics, somatic cells count (SCC) and mastitis in dairy cows. A total of 920 teats of 230 Lithuanian Black and White cows were evaluated to assess teat-end conditions and the thermographic characteristics were determined before evening milking. Teats of the animals were grouped into four different classes of hyperkeratosis. Additionally, quarters of udder were divided into three different classes based on the California mastitis test (CMT) and clinical signs: group 1 (healthy), group 2 (subclinical mastitis), and group 3 (clinical mastitis). The 44.3% of the teats were given a score of N (No ring), 41.1% of the teats were scored S (smooth ring), 11.8% of teats were given a score R (rough ring) and 2.9% of teats were given a score VR (very rough skin). The N and S groups had more healthy udder quarters than R and VR groups (P<0.001). Analysis of thermographic images at the teat sinuses showed that group 1 had lower teat temperature (0.93-1.32 0 C) than group 2 and group 3 (P<0.01). There was a significant positive correlation between milk SCC and temperature of the teats evaluated by hyperkeratosis scores N, S, and R. The results of the present study clearly showed that there was a significant connection between different levels of hyperkeratosis and teat temperature in all groups, indicating a greater risk to mastitis.

Indian Journal of Animal Research, 2017

The objective of study were to determine the effectiveness of Ovalbumin-LHRH-7 (OL) protein admin... more The objective of study were to determine the effectiveness of Ovalbumin-LHRH-7 (OL) protein administered with cytosine guanine (CpG) adjuvant and Incomplete Freund’s Adjuvant (IFA), and used one-shot immunization (single-dose vaccination) protocol in which booster dose included in microspheres in rams. Fifty ram lambs at about a year old were used. Treatment groups receiving Ovalbumin LHRH and control contained 10 animals. They were stratified according to age (weeks), live weight and scrotal circumference size, and were randomly assigned to five groups. Scrotal circumference, sexual activities and the numbers of rams having sperm in the ejaculate were affected from treatment (P less than 0.05) depending on the dose and vaccination protocol. However, immunization did not affect live weight changes in any treatment groups (P>0.05). Findings clearly demonstrate that the effects of OL immunization on reproductive traits in yearling rams were prominent when it was administered at hig...

Revista Brasileira de Zootecnia, 2016

The objective of this study was to determine the sexual parameters in young bucks with different ... more The objective of this study was to determine the sexual parameters in young bucks with different sexual activity and the effect of experience (age) on sexual parameters in bucks. Fifteen young, sexually inexperienced (SI) and five adult, sexually experienced (SE) Saanen × Hair goat crossbred bucks were used in this study. Bucks were individually exposed to three estrus does for 15-min periods during four sexual performance tests, which were carried out every other day to determine some sexual behavior traits such as flehmen response, reaction time, and ejaculation efficiency. Sexually inexperienced young bucks were evaluated based on their sexual activity (active (AC) vs inactive (IA)) and presence of horn. It was found that AC bucks had significantly higher serum testosterone concentrations (31.5 vs 21.5 ng/mL) and weight loss (114.2 vs 51.2 g/day) than IA bucks. In addition, weight loss was significantly correlated with ejaculation efficiency in young bucks. On the other hand, horned bucks tended to have higher ejaculation efficiency with significantly longer reaction time than polled bucks. For experience (age) classes, SE bucks had higher testosterone concentration (76.0 vs 31.5 ng/mL) and weight loss (16.7 vs 8.6%) than SI active young bucks. However, the effect of experience on other sexual performance traits was found to be limited. Overall, these results indicate that testosterone concentration may affect sexual performance of young bucks in the mating season. Age-related sexual experience is not a determining factor for sexual performance in bucks. However, sexual performance data alone may not reflect reproductive outcomes without semen data.

Tarım Bilimleri Dergisi, 2009

Öz: Bu çalışma, Akkaraman varyetesi Norduz ve Karakaş koçlarında eşeysel davranış özelliklerinin ... more Öz: Bu çalışma, Akkaraman varyetesi Norduz ve Karakaş koçlarında eşeysel davranış özelliklerinin yaşa göre değişimini belirlemek amacıyla yapılmıştır. Bu amaçla koçlar, yaşlarına göre iki gruba ayrılmış; birinci ve ikinci grubu sırasıyla 3≥ ve 2 yaşlı koçlar oluşturmuştur. Eşeysel davranışların belirlenmesi için birinci (n=7) ve ikinci grup (n=5) koçlar bireysel olarak 2 günde bir 15 dakika süreyle 3-5 kızgın koyunla test edilmiştir. Çalışmada incelenen davranış özelliklerinden flehmensiz genital organları koklama (FSGOK), flehmenli genital organları koklama (FGOK), kuyruk kaldırma (KK), ses çıkarma (SÇ), ejakulasyonsuz (EJSBS) ve ejakulasyonlu biniş sayısına (EJBS) ilişkin ortalama değerler sırasıyla; 4.65±0.53, 2.08±0.19, 8.58±0.97, 62.90±6.30, 38.73±3.04 ve 1.29±0.19 bulunmuştur. Biniş süresi (BS), ejakulasyon süresi (ES) ve ejakulasyon etkinliğine (EJET) ilişkin en küçük kareler ortalamaları sırasıyla; 0.65±0.11 dk, 5.16±0.71 dk ve 0.05±0.006 olarak belirlenmiştir. Çalışmada 3≥ yaş grubu koçlar kuyruk kaldırma, ses çıkarma, ejakulasyonlu biniş sayısı, ejakulasyon süresi ve ejakulasyon etkinliği bakımından 2 yaş grubu koçlardan üstün bulunmuştur (P<0.05). Eşeysel etkinlik testinin özellikle 2 yaşlı koçlarda incelenen özellikler bakımından bir iyileşme sağlamadığı gözlenmiştir.

Iranian Journal of Applied Animal Science, 2013

Archives Animal Breeding, 2016

In this study, we aimed to determine the slaughter-carcass characteristics, meat quality, and fat... more In this study, we aimed to determine the slaughter-carcass characteristics, meat quality, and fatty acid composition in lambs raised under intensive and extensive conditions. The animal material consisted of 30 Norduz male lambs, with an average age of 171 days. The lambs were divided into two groups: concentrate-fed lambs (CO) and pasture-fed lambs (PS). The results showed that the CO lambs had heavier carcasses (p< 0.001), a higher dressing percentage (p< 0.001), and higher intramuscular fat (p< 0.01) than the PS lambs. It was determined that the longissimus thoracis muscle of the CO lambs had a lower ultimate pH and higher L * and water-holding capacity than the PS lambs. In this study, intramuscular fat (longissimus thoracis, semimembranosus, triceps brachii), subcutaneous and tail fat samples were used to evaluate the effect of feeding system on fatty acid composition. The polyunsaturated fatty acid to saturated fatty acid ratio (PUFA / SFA) of intramuscular fat was found to be significantly higher in the CO group than in the PS lambs, while similar subcutaneous and tail fat results were found in both groups. Moreover, the PS lambs had a lower n6 / n3 ratio and higher percentage of omega-3 than the CO lambs in all tissues studied (p< 0.05). Overall, the CO lambs have heavier and fattier carcasses with better meat quality traits than the PS lambs. However, the effects of feeding system have varying results based on the fatty acid composition of different types of fat deposits. beneficial FAs, whereas concentrate-fed lambs have higher growth rates, better carcass conformation, a less problematic ultimate pH, and a higher n6 / n3 ratio (Wood et al., 2008; Zervas and Tsiplakou, 2011). Although ruminal biohydrogenation is the main factor in modifying dietary unsaturated fatty acids, the n-3 FA content differences between pasture and concentrate, in particular, make the feeding system important. The quantity and structure of FA intake modulates the metabolism, physiology, and immune response in humans, and, therefore, changes in the FA intake affect the risk of developing some chronic diseases, particularly cardiovascular diseases. Thus, increasing n-3 FA content is the common goal of the strategies to improve the lipid profile of meat (Bessa et al., 2015).

iftlik hayvanlarında üremenin denetimi hayvanların doğal üreme sistemlerinin sistematik olarak in... more iftlik hayvanlarında üremenin denetimi hayvanların doğal üreme sistemlerinin sistematik olarak insan eliyle dönüştürülmesini hedeflemekte ve bu amaçla pek çok teknik geliştirilmektedir. Son yıllarda spermatogenesisin temel mekanizmasını anlamaya yönelik pek çok çalışma yapılmakta ve erkeklerde infertilitenin temel nedenleri moleküler düzeyde araştırılmaktadır. Özellikle spermatogonial kök hücreleri spermatogenesisin başlangıç noktasını oluşturan temel bir araç olarak söz konusu amaç için önemli bir materyaldir. Bu hücrelerin tür içinde ve türler arasında transferlerinin başarılması etkinliklerini daha da artırmaktadır. Ancak spermatogonia kök hücresinin tanımlanması noktasında uygun belirteçlerin (markers) saptanması konusunda hala ciddi bir ilerleme kaydedilememiştir. Bu bağlamda bir başka önemli konu, artan çalışmalar spermatogenesisin karmaşık bir süreçler bütünü olduğunu göstermekte ve üreme biyolojisi konusundaki bilgilerimizin yeniden gözden geçirilmesi gerektiğini açığa çıkarmaktadır. Sonuç olarak spermatogonial kök hücreleri hem hayvancılıkta hem de tıpta kullanım olanakları bakımından umut vaat etmektedir. ABSTRACT he control of the reproduction in domesticated animals target to be converted by human their natural reproduction systems and for this aim; the many techniques have been developed. In recent years, to understand the basic mechanism of spermatogenesis the many studies have been performed and the main reasons of infertilities in male have been investigated at molecular level. Especially, spermatogonial stem cells are vehicle to research the biology of spermatogenesis because they begin spermatogenesis process. The importance of these cells is enhanced by managing the transplantation within species and between inter-species. At present, the main problem is that there is still not serious progress to characterize the spermatogonia stem cell, except for several markers. In this sense another topic increasing studies has been showed that spermatogenesis is a complicated process and that is came out to be re-evaluated our present biology knowledge. Lastly, spermatogonial stem cells presents the immense promise both domesticated animal breeding and human medicine

In this research, growth performance of Norduz kids and milk yield of Norduz goats, a native gene... more In this research, growth performance of Norduz kids and milk yield of Norduz goats, a native gene resource in Turkey, were defined. The animals studied were brought from natural habitats to the animal research farm of Agricultural Faculty, Yuzuncu