Mating Season Influences Placental Characteristics, Plasma IGF Concentration, and mRNA Expression without Affecting Lamb Birth Weight in Akkaraman Ewes

Seasonal variations signifcantly impact lambs’ birth weight and post-natal growth of lambs, yet the underlying physiological mechanisms remain insufciently explored. Terefore


Introduction
Generally, Akkaraman ewes adhere to a conventional mating season extending from September to October (early autumn), with lambing taking place during the last months of winter (February and March) [1].Nevertheless, lambs are also born outside this traditional breeding window because rams are reared with ewes in one fock throughout the year, which is characteristic of extensive Akkaraman breeding [1,2].While year-round mating ofers advantages in lamb meat production, the seasonal conditions may cause differences in lambs' pre-and post-natal growth and development [3].Te consequences of lambing during diverse seasons are particularly pronounced in extensive farming conditions, where environmental factors, notably the availability of vegetation, play a pivotal role.Terefore, inadequate management of nutritional resources during "out-of-seasonal" lambing can lead to adverse outcomes in meat production [4,5].Previous studies reported that lambs born in the autumn or winter had lower birth weights than spring-born lambs [6,7].Te quality and nutrient content of the pasture varies in diferent seasons due to the annual intensity of sunlight, temperature, and precipitation differences [3,[7][8][9][10], causing maternal nutrition supply to change throughout the year.For example, seasonal fuctuations in forage supply on natural pastures or rangelands can cause malnutrition among pregnant ewes, reducing lamb birth weights [6,7].However, diferences in maternal nutrition levels do not entirely account for the seasonal efect on birth weight.Seasonal changes in reproductive activity are strongly infuenced by changes in photoperiod and temperature, afecting the secretion patterns of hormones from the pineal and pituitary glands, such as melatonin, prolactin, and growth hormone [5,7,11,12].Tese seasonal fuctuations in reproductive hormones also afect placental and foetal growth and development.
Te placenta is a temporary organ that develops from the blastocyst shortly after implantation [13,14].Te placenta contributes primarily to the intrauterine environment for foetal growth and development [15,16].Te placenta contains structures known as cotyledons, which exchange respiratory gases, nutrients, and metabolic waste between the maternal and foetal bloodstreams [13].Although the foetal genome plays a vital role in growth potential, the placenta's size and cotyledon's number signifcantly infuence nutrient transfer capacity from the dam to the foetus, infuencing the pre-natal growth trajectory [13,17].Placental characteristics are one of the leading indicators affecting the post-natal survival of ofspring in small ruminants [14,16,18,19].Mellor and Staford [20] reported that the post-natal viability of newborns is associated with placental growth and development during gestation.Te exchange capacity of the mammalian placenta between maternal and foetal systems depends on the placental size and number of placentomes [13,17].Terefore, the placenta size, cotyledons number, and density, which are related to the nutrient transfer capacity, play a pivotal role in determining the pre-natal growth trajectory of the foetus and, hence, birth weight and post-natal viability [13,16,17].Placental efciency (PE), a marker of placental function, is commonly assessed by the ratio of birth weight to placental weight [21].Generally, high PE values associated with averaged-sized foetuses represent placentas with a greater nutrient transport capacity.In contrast, low PE values linked to growth-restricted foetuses represent placentas with a reduced nutrient transport capacity or a failure to adapt.To enhance our understanding of PE, new productivity parameters, cotyledon efciency (CE) and volumetric cotyledon efciency (VCE), are used to measure the efciency of cotyledons [18,22].CE and VCE are used as newly adopted methods to measure the individual and total surface area of all cotyledons on the placenta of each animal rather than simply determining the total number and weight of cotyledons.Many studies have observed the efects of maternal nutrition level during pregnancy on placental development [16,17,23,24].Terefore, diferences in maternal feed intake during pregnancy, depending on seasonal pasture quality in a pasture-based rearing system, may afect the development of the placenta and the foetus.
IGFs are nutritionally sensitive proteins that regulate foetal and placental growth and development [25][26][27].Previous studies reported that the expression and secretion of IGFs increase cell proliferation and mitogenesis and regulate apoptosis [13,25].Also, IGFs function as cell cycle promoters, stimulating DNA synthesis and cell diferentiation in cultured embryos and numerous foetal cell lines [28].Studies on sheep have demonstrated that IGFs, whether transferred to the foetus or mother, infuence the transfer and distribution of glucose and amino acids between foetal and uteroplacental tissues [27,29].IGF-I stimulates foetal growth; IGF-II may indirectly afect the foetus by modifying the placenta's ability to provide nutrients and promote growth [13,25,30].
Previous studies have investigated the efect of season on diverse aspects such as placental development, lamb's daily weight gain, meat quality, birth weight, and mortality rate [3,4,7,11,31].However, knowledge about the efects of seasonal diferences on placental development, placental mRNA expression level of IGFs, and maternal plasma IGF concentration, especially in indigenous breeds, could be improved.Terefore, this study aimed to examine the mating season's efect on the lamb's birth weight, placental characteristics, placental mRNA expression level of IGFs, and maternal plasma IGF concentration in Akkaraman ewes.

Materials and Methods
Te animal study protocol was approved by the Local Animal Care and Ethics Committee of Kirsehir Ahi Evran University, Kirsehir, Türkiye (protocol code 68429034/14 and January 27, 2018), ensuring compliance with EC Directive 86/609/EEC for animal experiments.Te study used 100 adult Akkaraman ewes with an average body weight of 54.1 ± 2.7 kg and body condition score of 2.5 ± 0.3.All ewes had given birth at least twice.For mating purposes, two three-year-old fertile and healthy Akkaraman rams with an average body weight (73.6 ± 4.2 kg) and body condition scores (2.9 ± 0.1) were selected.All ewes and rams were reared at a private farm in Kirsehir, Türkiye (38 °55′ 56.8″N, 34 °10′ 45.6″E, and 985 m above sea level), under extensive conditions.In the study, continuous mating (uncontrolled mating) was applied.Te rams were allowed to interact freely with ewes day and night.Rams were coreared with ewes throughout the year, and the ewes were introduced to Akkaraman rams for the frst time in September.Te mating seasons of ewes were determined according to the birth seasons.Te ewes mated in the breeding season gave birth between February and March, and the ewes mated during the out-of-breeding season gave birth between September Veterinary Medicine International and October.Te study examined only the characteristics of ewes giving birth to singleton males.Consequently, thirtyeight ewes that gave birth to twins (n � 21) or females (n � 17) were excluded from the study to avoid litter size and sex efects on placental characteristics.Te fnal analysis was conducted on sixty-two Akkaraman ewes, which gave birth to a singleton male lamb.Tese ewes were divided into mated during the breeding season (between September and October; n � 35) and out-of-breeding season (between April and May; n � 27).Te ewes mated in breeding and out-ofbreeding seasons exhibited similar body weights (55.1 ± 2.5 kg and 52.8 ± 2.9 kg, respectively) and body condition scores (2.6 ± 0.2 and 2.5 ± 0.4, respectively).
Monthly averages of outdoor temperature ( °C) and rainfall rate (kg/m 2 ) throughout the experimental period were obtained from the Turkish State Metrological Service and are presented in Figure 1.Te ewes were freely grazed in the pasture for at least fve hours daily during both the frst and second trimesters of pregnancy.Te grazing areas were natural grasslands with a very low legume composition.Te Poaceae species, Festuca ovina, Hordeum murinum, andAegilops triuncialis and the species belonging to other families Avena barbata, Mentha arvensis, andTymus sp. are the most common plant species in these areas [10].Additionally, each ewe was ofered 50 g/day of concentrates (89.5% DM, 23.4% crude protein, and 10.9 MJ•ME/kg DM) and 0.5 kg/day of wheat straw (91.2% DM, 4.6% crude protein, and 4.18 MJ•ME/kg DM) during the pregnancy's frst and second trimesters.During the third trimester of gestation, the ewes were allowed to pasture and also received 100 g/day of concentrates and 1 kg/day of wheat straw.Te daily dietary regimen was divided into two meals, administered at 08:30 and 16:30.Tis feeding protocol aimed to ensure optimal nutrition and well-being for ewes throughout the diferent stages of pregnancy.

Placental Measurements and Sample Collection.
Following lambing, the lamb birth weight (LBW) was determined, and in both seasons, the naturally expelled placenta was collected.Placental weight (PW) was determined with discharged placental fuid before weighing.Te numbers (TCN) and weights (TCW) of cotyledons, which were dissected from the chorioallantois, were also recorded.Te length (CL), width (CWi), and depth (CDe) of all cotyledons were measured using an electronic digital compass.Te subsequent classifcation of cotyledons based on length (CL) categorised them as small (<20 mm), medium (20-25 mm), and large (>25 mm).Only one randomly selected cotyledon from each size was covered with aluminium foil immediately following lambing frozen in liquid nitrogen and stored at −80 °C until the mRNA expression analysis of the IGFs.
Te cotyledons surface area (CSA) was calculated after the measurements of all cotyledons in the individual placenta as cm 2 with the following equation [14]: Placental efciency (PE) and cotyledon efciency (CE) were calculated as the ratio of LBW to the PW and the CSA, respectively.Tese ratios refect grams of lambs produced per gram of placenta and surface area of cotyledon.Additionally, the cotyledon volume (CV), volumetric cotyledon efciency (VCE), and cotyledon density (CD) were calculated using equations ( 2)-( 6), respectively [14].

Blood Sample Collection and the Plasma IGF Assays.
Blood samples (∼10 ml) were taken from the jugular vein of all ewes every month, from mating to parturition, using a vacutainer in sterile heparin tubes.Blood samples were centrifuged at 3400 rpm for 10 minutes at 4 °C, and plasma samples were stored at −20 °C until analysis of plasma IGF concentration.Te plasma IGF concentrations of ewes in both seasons were determined using the commercial ELISA kit (MyBioSource, sheep IGF-I, and IGF-II ELISA Kit, San Diego, USA).IGF concentrations in plasma samples were measured using an ELISA reader device (Termo Scientifc, Renfrew, UK) adjusted to 450 nm wavelength.In the reading process, the device was standardised according to the control (blind) wells, and then the measurement process was performed.Te concentration of IGFs in plasma samples was calculated according to the concentration of the standards and their respective OD (optical density) values using the standard linear regression curve equation.In the assay, the standard concentrations of IGF-I and IGF-II were 600, 300, 150, 75, and 37.5 ng/mL.Te R 2 values of IGF-I and IGF-II standard graphs were found to be 0.978 and 0.987, respectively.Assay sensitivity was 0.1 ng/ml with a coefcient of variation of 5% for IGFs.
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Total RNA Isolation, Synthesis of cDNA, and qRT-PCR
Analyses.Te cotyledons of diferent sizes obtained from each ewe in the experiment were pooled in a mortar and powdered with liquid nitrogen.Te total RNA was extracted from the cotyledon samples using the Trizol reagent (Invitrogen) according to the manufacturer's instructions.Genomic DNA was eliminated by digestion with RNase-free DNase I (Termo Fisher Scientifc Inc., Waltham, Massachusetts, USA).Te purity and concentration of isolated RNA were evaluated by the A260/A280 ratio using a NanoDrop ™ 2000/2000c spectrophotometer (Termo- Scientifc, Renfrew, UK), and all RNA samples showed A260/A280 values within the range of 2.01 to 2.08 and A260/ A230 values above 2. Te integrity was verifed by electrophoresis on a 1% agarose gel.Te total RNA was resuspended in 10 mL of bufer solution and stored at −80 °C until use in the qRT-PCR assay.Primers used for the amplifcation of genes were designed using the primer-BLAST tool of NCBI (https://www.ncbi.nlm.nih.gov/tools/primerblast/)based on the related ovine gene sequences (Table 1).
Te RNA samples were reverse-transcribed using the commercial cDNA kit (Bio-Rad iScript cDNA, 1708890) according to the manufacturer's Termal Cycler (Bio-Rad) device instructions.A Real-Time Quantitative Reverse Transcription polymerase chain reaction (qRT-PCR) assay was performed using the CFX96 Touch Real-Time PCR Detection System (Bio-Rad Laboratories, Hercules, California, USA).
Te qRT-PCR was conducted in a reaction system with a total volume of 10 μL containing the following components: 5 μL the 2X powerUpTM SYBRTM Green Master Mix (Termo Fisher Scientifc), 0.4 μL forward primer (10 μmol/ L), 0.4 μL reverse primer (10 μmol/L), 0.2 μL 50 × ROX Reference Dye, 3 μL 0.1% DEPC water, and 1 μL of cDNA (derived from 25 ng of total RNA) as a template.Te PCR protocol included an initial step at 50 °C for 2 min (one cycle), followed by 95 °C for 2 min (one cycle), and forty cycles of denaturation at 95 °C for 15 s and of denaturation at 60 °C for 1 min, with a single fuorescence measurement at the extension step.Upon completion of amplifcation, a fnal melting curve analysis (Tm) was followed by generating a thermal gradient from 60 °C to 95 °C with a ramp rate of 0.5 °C/s.Standard curves were made from serial dilutions of cDNA ranging from 50 to 5 × 10 −4 ng, equivalent to total RNA.Hence, reactions were optimised to maximise the IGFs' amplifcation efciency (>90%).Te GAPDH gene served as an internal reference gene for normalising the expression of the IGFs [25].Tree independent biological replicates of each treatment group were performed.Te relative expression levels of the genes were calculated by the 2 -ΔΔCt method [25].

Statistical Analysis.
Te efects of the mating season, treated as a fxed main efect, on placental characteristics, maternal IGF plasma concentration, and placental mRNA expression of IGFs genes were analysed using a completely randomised design by the one-way ANOVA procedure of the SPSS package program.Signifcant diferences between means were evaluated using Duncan's test, and results were computed as mean ± standard error of the mean (SEM) [32].Statistical signifcance was determined at a threshold of P < 0.05.Relationships between birth weight and placental characteristics were investigated through Pearson correlation analysis at the 95% confdence interval.Te Fisher Z transformation test was applied to assess the signifcance of the diferences between correlation coefcients for LBW and placental characteristics in both seasons [16].

Results
Table 2 presents the post-lambing body weights and body condition scores of ewes mated in breeding and out-ofbreeding seasons.Te body weights and body condition scores of ewes mated in both seasons were similar at the beginning of the study, but the post-lambing weight of ewes mated in the breeding season exhibited a tendency to be higher (excluding for body condition scores) than those mated in out-of-breeding seasons (P � 0.083).Te weight of total cotyledons was lower for ewes mated during the out-of-   3).Interestingly, while no signifcant diferences were detected between the mating seasons in terms of the measurement characteristics of the cotyledons, it was observed that the large cotyledons in the placentas of ewes mated the breeding season were thicker (P < 0.05) than those mated during the out-of-breeding season (Table 3).
Pearson correlation coefcients of placental characteristics and birth-related factors in Akkaraman mated during breeding and out-of-breeding season are presented in Tables 4 and 5, respectively.Tere were no signifcant correlations between LBW and placental characteristics in either of the seasons.Tere were positive correlations between PW and TCW, and negative correlations were observed between PW and CD, PE, and VCE for ewes mated during the breeding season.As expected in the study, there were positive correlations between TCN and CD in ewes bred in the breeding season.In addition to negative correlations between TCW and CE, TCW and CD, TCW and PE, and TCW and VCE were calculated in ewes mated during the breeding season.While the positive correlation between CV and CSA was calculated, negative correlations were obtained between CV, CE, and VCE in the breeding season.Positive correlations were found between VCE and CE, CD, and PE, whereas negative correlations were noted between CSA and CE and VCE.
In the out-of-breeding season, positive correlations were found between PW and TCW, CV, and CSA.Negative correlations were observed between PW and CE, CD, PE, and VCE in that season.Tere were positive correlations between TCN and TCW and CSA, but negative correlations were found between TCN and CV, CE, PE, and VCE for ewes mated during the out-of-breeding season.Although a positive correlation was calculated between CW and CSA, there was a negative correlation between TCW and PE for ewes mated in the out-of-breeding season.As expected, there was a positive correlation between CV and CSA, while negative correlations were calculated between CV and CE and CV and VCE for out-of-breeding season.Similarly, negative correlations between CSA and CE and VCE were obtained.Tere were positive correlations between CE and PE and VCE in ewes mated during the out-of-breeding season.A positive correlation between PE and VCE was calculated when ewes mated in the out-of-breeding season.
Te placental expression levels of IGF mRNA relative to GAPDH are presented in Figure 5. Tere were no signifcant diferences between mating seasons in terms of placental mRNA expression levels of IGF-I, but the expression level of IGF-II mRNA was higher (fold change: 2.84) for the ewes mated during the breeding season (P < 0.05) compared to the out-of-breeding season.

Discussion
Te present study indicated that mating season infuences some placental characteristics, maternal IGF-I plasma concentrations, and placental mRNA expression levels of IGF-II without afecting LBW in singleton-bearing Akkaraman ewes.Signifcant variations were observed regarding the correlation coefcient between LBW and some placental characteristics between mating seasons.Tis suggests an interplay between the mating season and placental characteristics, emphasising the need for a comprehensive understanding of these relationships.
In the northern hemisphere, the breeding season of sheep coincides with the early autumn and winter months (September through March) when the quality of pasture decreases [6,31,33].Terefore, inadequate maternal nutrition during the breeding season may decrease reproductive performance.Previous studies have demonstrated the signifcant role of maternal nutrition levels before and after mating and during gestation in infuencing reproductive performance [6,24,[34][35][36].Similarly, previous studies indicated the impact of seasonal diferences on placental and foetal development associated with LBW and post-natal growth [11,37].LBW stands out as one of the most critical factors afecting post-natal growth and survival until weaning, making it a pivotal concern for the sheep production industry [4,8,18,38].Even if the sheep exhibit estrus depending on the season, ewes can be mated yearround with various breeding practices (exogenous hormone applications, ram efect, etc.) [12].Te birth weight of lambs exhibits seasonality, refecting the infuence of environmental conditions of each season [4,8,11,37,39].Peterson et al. [11] and Reid et al. [39] reported that the birth weight of spring-born lambs tended to be higher than that of autumnborn and spring-born lambs.Also, spring-born lambs had higher growth rates compared to autumn-born lambs during the early post-natal period [11,39].However, Sušić et al. [4] reported no signifcant diferences in birth weight between spring-and autumn-born lambs.Similarly, in the present study, lambs of Akkaraman ewes mated during breeding and out-of-breeding seasons exhibited comparable birth weights.
Te Akkaraman sheep breed has high adaptability and resistance to adverse environmental conditions [2,18,40].Ewes of this breed have high survivability due to their fat tail and have an essential storage nutrient reserve against insufcient feeding periods [1,2,41].In seasons characterised by abundant and high-quality forage, the fat tissue in the tail is formed and grows resulting in an increase in both size and the number of fat cells.During seasons with insufcient forage, lipolysis occurs.Te diferent weather conditions in seasons can directly afect the herbage quantity and quality 6 Veterinary Medicine International of the pasture.Based on the results of the study by Kirbas [10], the rate of legumes in the pasture areas of the central Anatolia region of Türkiye, where the Akkaraman sheep breed is widely raised, was higher in the breeding season than in the out-of-breeding season.Also, it turns out that this corresponds to the pregnancy of Akkaraman ewes mating out-of-breeding season, which was relatively weaker and coincided with the dry period.Terefore, ewes mated during the out-of-breeding season may experience malnutrition during gestation.Most of the gestation period of ewes mated in the out-of-breeding season coincided with the period with low rainfall.

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In contrast, ewes mated during the breeding season experienced higher rainfall during a signifcant portion of their gestation period (Figure 1).Despite these environmental infuences, the absence of diferences in lamb birth weight between mating seasons in the present study was noted.One plausible explanation for this observation may be the occurrence of lipolysis of fatty tissue [42] in the tail during the gestation of Akkaraman ewes mated in the outof-breeding season.
Moreover, the fat amount of the tail during insufcient feeding periods may support foetal growth and development.Unfortunately, in the present study, the changes in the fat amount of the tail of Akkaraman ewes were not determined during pregnancy.However, there was a notable trend indicating that the decrease in body weight of ewes mated during the out-of-breeding season tended to be more pronounced from mating to the post-lambing period compared to ewes mated the during breeding season.Ewes bred in the out-of-breeding season were approximately 11.3% lighter after lambing than ewes mated in the breeding season.Tis observation may support the hypothesis that ewes mated in the out-of-breeding season during pregnancy might have utilised fat reserves in their tails.
Te placenta undergoes signifcant growth and development during mid-gestation to support foetal growth and development [13,43].In sheep, the placenta reaches maximum size by the 3 rd month of gestation, when the foetus gains only 1/10 of birth weight [43,44].Previous studies reported a positive relationship between LBW and PW [3,8,18,45,46].Terefore, abnormal or insufcient placental development can afect foetal growth and development.In the present study, although there was no diference    [13,43,44].Terefore, examining the post-natal development and adult productivity of lambs obtained from ewes mating in different seasons can be an essential contributor to revealing the efects of seasonal diferences in placental characteristics on the productivity of animals in the adult period.Previous studies have reported that IGFs are expressed and secreted by the sheep uterus and placenta [48,49].IGF-I and IGF-II mRNAs were detected in sheep embryos throughout pre-implantation development from the singlecell stage to the blastocyst stage [50].Following implantation, maternal uterine IGF-I mRNA expression was low, making it unlikely that locally expressed and produced IGF-I is essential for placental development [49].In contrast, expression of IGF-II mRNA in the placentome capsule and endometrial stroma continued throughout the frst half of pregnancy, and IGF-II mRNA expression increased in foetal mesodermal tissues from days 14 to 35 and remained elevated until birth [51].Overexpression of IGF-II is associated with an enlarged placenta [52].Gene deletion studies have shown that a defciency in placental development occurs in embryos carrying null mutations of the IGF-II gene, while IGF-I gene deletion does not infuence placental weight [26,[53][54][55].IGF-II has a stimulatory efect on the growth of the placenta, but this efect is not mediated through IGF-I [56].However, Osgerby et al. [47] reported that maternal plasma IGF-I concentration positively correlates with the total placentome number, and higher levels of values are observed in ewes in good condition.Te results of the present study showed that mating season did not infuence the placental mRNA expression level of IGF-I.However, increased IGF-II mRNA expression was observed in the ewe mated during the breeding season.Interestingly, maternal plasma IGF-II concentrations in ewes mated in both seasons were similar.In contrast, the concentration of IGF-I was higher at the 3 rd month of gestation in ewes bred during the breeding season.Te higher total number and weight of cotyledons in ewes mated during the breeding season may have resulted from higher placental IGF-II mRNA gene expression level and maternal plasma IGF-I concentration [13,15,27,29].Tus, these observations confrmed that mating season exerts an infuence on placental growth and development through alterations in plasma concentration and mRNA expression of IGFs [7,13,15,37].

Conclusion
In conclusion, the results of the present study imply that mating season infuences placental characteristics without afecting lamb birth weight in Akkaraman ewes.Ewes mated during the out-of-breeding season exhibited diferent placental morphology, potentially leading to alterations in placental sufciency.Diferences in placental characteristics, especially in the total number and weight of cotyledons, of ewes mated in diferent seasons may be attributed to differences in maternal plasma IGF-I concentration and placental IGF-II mRNA expression.Terefore, further studies are needed to understand the efects of seasonal diferences in extensive sheep breeding on placental characteristics on lambs' post-natal growth and adult productivity.numbers: PYO-ZRT.A3.16.007 and PYO-ZRT.A4.17.001) to carry out this study is gratefully acknowledged.Open-access funding was enabled and organized by TUBITAK 2023.

Figure 1 :
Figure 1: Monthly averages of outdoor temperature ( °C) and rainfall rate (kg/m 2 ) during the experimental period.

Figure 5 :
Figure 5: Te placental expression levels of IGF mRNA relative to GAPDH in Akkaraman ewes mated during the breeding and outof-breeding seasons.Bars indicate means ± SE. * P < 0.05.

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Veterinary Medicine International breeding season compared to ewes mated during the breeding season (P < 0.05), which was represented by the diference in the large cotyledon weight between the seasons (Table2).Te total number of cotyledons in the placenta of the ewes mated in the breeding season was higher than those mated during the out-of-breeding season (68.3 ± 2.3 vs. 60.9 ± 3.1; P < 0.05).No diferences were found in the numbers of small (27.3 ± 2.4 vs. 21.4 ± 2.8), medium (29.2 ± 1.5 vs. 25.3 ± 2.1), and large cotyledons (11.8 ± 1.1 vs. 14.2 ± 2.4) between seasons.Although PE, CE, CD, CV, and CSA were similar in both mating seasons, VCE was higher (P < 0.05) for ewes mated during out-of-breeding compared to ewes bred in the breeding season (Table

Table 1 :
Details of primer pairs used for ovine RT-PCR reactions.

Table 2 :
Post-lambing body weights and body condition scores of ewes, along with lambs' birth weights and placental traits (means ± SEM).

Table 3 :
Morphometric characteristics and various efciency traits of placenta and cotyledons (means ± SEM).

Table 5 :
Pearson correlation coefcients of placental characteristics and birth-related factors in singleton lambs born from Akkaraman ewes mated during out-of-breeding season.
P < 0.05.Veterinary Medicine International between LBW and PW in mating seasons, signifcant differences were observed in total cotyledon number and weight.Te diference in weight of the total cotyledon stemmed from ewes mated in the breeding season having heavier large cotyledons.Tis, in turn, was attributed to the thicker large cotyledons during the mating season. *