Small Ruminant Research最新文献

{"title":"Tracing roots: A study on phylogenetic and genetic diversity in indigenous sheep breeds of Southwestern Türkiye","authors":"Nezih Ata ,&nbsp;Zühal Gündüz ,&nbsp;Duygu Kaşıkçı ,&nbsp;Tülay Canatan ,&nbsp;İbrahim Cemal ,&nbsp;Onur Yılmaz","doi":"10.1016/j.smallrumres.2025.107521","DOIUrl":"10.1016/j.smallrumres.2025.107521","url":null,"abstract":"<div><div>This study aimed to elucidate the genetic diversity and population structures of indigenous sheep breeds in the southwestern region of Türkiye, thereby addressing the existing gap in molecular genetic information for these breeds. The animal materials used in the study were selected based on the sampling criteria established by the FAO (2011). It included a total of 331 sheep, comprising Dağlıç (48), Eşme (80), Pırlak (29), Pırıt (103), Sakız (37), and Kıvırcık (37), breeds, raised in 6 different provinces of Western Anatolia. A comprehensive analysis of 18 microsatellite loci revealed a diverse range, detecting a total of 493 alleles in the study. The average allele number (Na), effective allele number (Ne), observed heterozygosity (Ho), expected heterozygosity (He), polymorphic information content (PIC), and F_IS values were 27.39, 9.54, 0.70, 0.88, 0.87, and 0.158, respectively. In this study, F_ST and G_ST analyses indicate that genetic diversity is predominantly distributed within breeds, whereas genetic differences between populations are minimal. Indeed, the G_ST value indicated that only 6.1 % of the total genetic variation was attributable to differences between populations. Hardy-Weinberg Equilibrium (HWE) analyses suggest that genetic balance has been disrupted in all populations due to intense artificial selection pressures. These deviations are believed to result from factors such as a lack of random mating, inbreeding, and genetic drift. Especially strong gene flow was detected between the Pırlak-Kıvırcık and Eşme-Pırıt population pairs. The unique alleles of the Pırıt breed highlight its genetically distinct structure. This study offers significant findings for sustainable animal breeding and the conservation of genetic resources. These results serve as a valuable foundation for the genetic management of sheep breeds in Türkiye.</div></div>","PeriodicalId":21758,"journal":{"name":"Small Ruminant Research","volume":"249 ","pages":"Article 107521"},"PeriodicalIF":1.6,"publicationDate":"2025-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143936982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of propolis extract on performance, health and immune parameters in lambs","authors":"Ozge Kabiloglu ,&nbsp;Ismail Abas ,&nbsp;Neşe Kocabaglı","doi":"10.1016/j.smallrumres.2025.107522","DOIUrl":"10.1016/j.smallrumres.2025.107522","url":null,"abstract":"<div><div>This study aimed to investigate the effects of the ethanol extract of propolis (EEP), a natural substance derived from bees, on growth performance, selected health parameters, and immune responses in weaned lambs. A total of 30 male Trakya Kıvırcık lambs (14 ± 2 weeks old; 24.2 ± 1 kg) were randomly divided into three groups: EEP0 (control), EEP3 (3 mL/day), and EEP6 (6 mL/day). The treatments were administered orally each morning before feeding for a duration of 42 days. Growth performance parameters (body weight, body measurements, feed intake, feed conversion ratio, and weight gain) and health indicators (heart rate, respiratory rate, rectal temperature, and cough score) were monitored weekly. Immune parameters, including serum levels of IgA, IgG, and IgM, were evaluated on days 0, 21, and 42 of the trial. The results showed that EEP supplementation had no significant effect on body weight or body measurements (P &gt; 0.05). Although total weight gain differences among groups were not statistically significant (P = 0.056), a pairwise comparison revealed a significant increase in weight gain in the EEP6 group compared to the control (P = 0.029). No significant differences were observed in total dry matter intake (P = 0.331), while the feed conversion ratio was significantly improved by EEP supplementation (P = 0.002). EEP had no significant effect on health parameters except for cough score (P &gt; 0.05). Notably, the EEP6 group demonstrated a significantly lower the cough frequency following tracheal stimulation (P &lt; 0.001). Serum IgG levels did not differ between groups (P &gt; 0.05), whereas both IgA and IgM levels tended to be higher in the EEP6 group on days 21 and 42 (P &lt; 0.05). In conclusion, the daily administration of 6 mL EEP (equivalent to 1800 mg propolis) in weaned lambs showed potential benefits in terms of weight gain, feed efficiency, cough response, and certain immune parameters (IgA and IgM).</div></div>","PeriodicalId":21758,"journal":{"name":"Small Ruminant Research","volume":"249 ","pages":"Article 107522"},"PeriodicalIF":1.6,"publicationDate":"2025-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143916335","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lamb survival and ewe longevity in a crossbreeding program between indigenous and exotic sheep in semi-arid lands","authors":"E. Oyieng ,&nbsp;J.M.K. Ojango ,&nbsp;M. Gauly ,&nbsp;R. Mrode ,&nbsp;A.M. Okeyo ,&nbsp;S. König","doi":"10.1016/j.smallrumres.2025.107520","DOIUrl":"10.1016/j.smallrumres.2025.107520","url":null,"abstract":"<div><div>The survival of lambs and longevity of ewes within flocks are important for the sustainability of sheep populations especially in arid and semi-arid lands (ASAL). In this study we conducted pre- and post-weaning survival analysis of lambs and the longevity of ewes of indigenous pure Red Maasai (RRRR), pure Dorper (DDDD), and their crosses comprising F1 (DDRR) and 75 %Dorper-25 %Red Maasai (DDDR) using Cox and Weibull proportional hazard models. The objective was to determine the genetic and non-genetic factors affecting lamb survival to yearling as well as ewe longevity. Data comprised records on 6313 lambs and 2003 ewes. Overall pre-weaning mortality was lower (5 %) compared to post-weaning mortality rate (17 %). Lambs born during the long dry season had a higher risk of dying than those born during the wet seasons. For both lambs and ewes, the Dorper had the highest risk of dying or being culled. Among the crossbreds, the DDDR lambs and ewes had higher risks of dying or being culled relative to F1 lambs and ewes. The risk of ewes being culled reduced with increasing age at first lambing and parity. Heritability estimates for pre-weaning mortality were higher (0.10–0.14) than post-weaning mortality (0.01–0.05). The higher heritability for pre-weaning lamb survival in indicates greater genetic variation, presenting an opportunity for selection for lamb survival. Interventions to improve the production environment in the ASAL areas would also improve the survival of lambs and longevity of ewes.</div></div>","PeriodicalId":21758,"journal":{"name":"Small Ruminant Research","volume":"249 ","pages":"Article 107520"},"PeriodicalIF":1.6,"publicationDate":"2025-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143907569","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Milk pregnancy-associated glycoprotein concentration as an early detection biomarker of multiparous pregnancies in alpine goats","authors":"Y.T. Chen ,&nbsp;M.K. Yang ,&nbsp;H.T. Hong ,&nbsp;J.M. Li ,&nbsp;C.P. Wu ,&nbsp;Y.H. Yeh ,&nbsp;Y.H. Chen ,&nbsp;J.W. Shiau ,&nbsp;P.A. Tu","doi":"10.1016/j.smallrumres.2025.107519","DOIUrl":"10.1016/j.smallrumres.2025.107519","url":null,"abstract":"<div><div>This study analyzed weekly milk samples from 348 pregnant goats among 550 multiparous Alpine goats after artificial insemination, measuring pregnancy-associated glycoprotein (PAG) concentrations. Fetal numbers were recorded postpartum. PAG levels progressively increased from mid-gestation, peaking before delivery. From day 49, goats carrying multiple fetuses exhibited PAG concentrations approximately 2.5 times higher than those carrying single or twin fetuses. Multivariate linear analysis showed that milk PAG levels during early and mid-gestation were influenced by both fetal number and gestational age, whereas late gestation levels were only affected by fetal number. Receiver operating characteristic analysis identified a PAG threshold of 2.643 on day 57, effectively distinguishing goats carrying multiple fetuses (Sensitivity: 100 %, 95 % CI = 91.0–100 %; Specificity: 100 %, 95 % CI = 95.5–100 %). Canonical discriminant analysis further confirmed significant differences in PAG concentrations between days 49 and 57 for single, twin, and multiple pregnancies. These findings demonstrate that milk PAG concentration is a reliable biomarker for detecting multiple pregnancies in early pregnancy, allowing timely management interventions to prevent metabolic diseases in goats with multiple fetuses.</div></div>","PeriodicalId":21758,"journal":{"name":"Small Ruminant Research","volume":"249 ","pages":"Article 107519"},"PeriodicalIF":1.6,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143911684","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Determinants that influence women empowerment – an empirical study on small ruminant rearer in rural areas of Bangladesh","authors":"Meherunnesa Chowdhury Sumy ,&nbsp;Md Salman ,&nbsp;Md. Manirul Islam ,&nbsp;Fakir Azmal Huda ,&nbsp;Sadika Haque","doi":"10.1016/j.smallrumres.2025.107514","DOIUrl":"10.1016/j.smallrumres.2025.107514","url":null,"abstract":"<div><div>The Women Empowerment in Agriculture Index for Small Ruminant Rearer (WEAI-SRR) was measured by adapting the WEAI (The Women Empowerment in Agriculture Index) tool to evaluate the empowerment status of women small ruminant rearer’s in Bangladesh. The objective was to explore the determinants that influence women’s empowerment. A multistage survey technique was used to collect information from 320 rural women from four districts of Bangladesh. The results of WEAI-SRR showed that 18 % women were empowered in five domains of empowerment (5DE&gt;0.80). The results of quantile regression model indicated that training has a statistically positive effect, but access to credit has a negatively significant effect on women empowerment. Providing more training on small ruminant rearing and ensuring proper credit use could magnify the status of overall empowerment of the women small ruminant rearers. So, the government and policymakers should introduce different programmes on small ruminant rearing in Bangladesh to increase the empowerment status of rural poor women.</div></div>","PeriodicalId":21758,"journal":{"name":"Small Ruminant Research","volume":"248 ","pages":"Article 107514"},"PeriodicalIF":1.6,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143908267","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of dicyclomine hydrochloride on physiological variables, duodenal motility, fibrinogen and total antioxidant capacity in kid goats subjected to endotoxemia","authors":"Shahab Shams,&nbsp;Aliasghar Chalmeh,&nbsp;Mehrdad Pourjafar,&nbsp;Armin Amirian","doi":"10.1016/j.smallrumres.2025.107518","DOIUrl":"10.1016/j.smallrumres.2025.107518","url":null,"abstract":"<div><div>Endotoxemia, resulting from the systemic release of lipopolysaccharides from Gram-negative bacteria, often leads to increased gastrointestinal (GI) motility and diarrhea in livestock, posing significant therapeutic challenges. Traditional treatments have limited efficacy in controlling these hyperdynamic GI clinical signs. This study aimed to evaluate the dual role of dicyclomine hydrochloride in modulating GI motility and systemic inflammation in a kid goat model of endotoxemia and to determine its effective clinical dose for managing these conditions. Thirty clinically healthy, four-month-old female kid goats were randomly assigned to six equal groups: control with LPS (Ctrl+), control without LPS (Ctrl−), dicyclomine at 0.5 mg/kg (DCMN1), dicyclomine at 1 mg/kg (DCMN2), dicyclomine 0.5 mg/kg plus LPS (DCMN1 +LPS), and dicyclomine 1 mg/kg plus LPS (DCMN2 +LPS). Endotoxemia was induced using an intravenous injection of LPS (0.1 μg/kg). Dicyclomine hydrochloride was administered intramuscularly at 0 h (immediately before the drug administration as baseline). Clinical parameters, GI motility via ultrasonography, and biochemical markers—including fibrinogen, total antioxidant capacity, and cholecystokinin (CCK) levels—were evaluated at multiple time points up to 10 h post-treatment. The Ctrl+ group exhibited significant increases in heart rate (HR), rectal temperature (RT), fibrinogen levels, total antioxidant capacity, and duodenal motility, confirming the induction of endotoxemia and associated hyperdynamic GI activity (P &lt; 0.001). Dicyclomine administration significantly reduced duodenal segmental and peristaltic movements in a dose-dependent manner, with the 1 mg/kg dose showing greater efficacy (P &lt; 0.001). Additionally, dicyclomine-treated groups demonstrated lower fibrinogen and total antioxidant capacity levels compared to the Ctrl+ group, indicating its anti-inflammatory effects (P &lt; 0.05). No significant changes in CCK levels were observed among the groups. Dicyclomine hydrochloride effectively reduced hyperdynamic GI motility and alleviated systemic inflammatory responses in endotoxemic kid goats, with the 1 mg/kg dose demonstrating superior efficacy. These findings suggest that dicyclomine may serve as a valuable therapeutic agent for managing GI disturbances and inflammation associated with endotoxemia in livestock.</div></div>","PeriodicalId":21758,"journal":{"name":"Small Ruminant Research","volume":"248 ","pages":"Article 107518"},"PeriodicalIF":1.6,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143898898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of day length on orexin A levels in blood, cerebrospinal fluid and various brain tissues in seasonally breeding sheep","authors":"Katarzyna Kirsz,&nbsp;Małgorzata Szczęsna,&nbsp;Weronika Biernat,&nbsp;Dorota A. Zięba","doi":"10.1016/j.smallrumres.2025.107516","DOIUrl":"10.1016/j.smallrumres.2025.107516","url":null,"abstract":"<div><div>Orexin A (OXA) is a key regulator of the sleep-wake cycle and energy homeostasis in mammals. In rodents, OXA synthesis follows a circadian rhythm positively associated with wakefulness. While similar research is lacking in seasonal animals, we previously demonstrated that OXA mediates photoperiodic effects on reproduction and metabolism in seasonally breeding sheep. This study investigated whether circadian and seasonal rhythms in OXA secretion occur in sheep and how they correspond to tissue-specific concentrations under different photoperiods. Ten adult ewes were kept under natural conditions during long-day (LD; May, nonbreeding season; ∼16 h daylight; n = 5) and short-day (SD; November, breeding season; ∼9 h daylight; n = 5) periods. The experiments were conducted separately for each season to distinguish photoperiodic effects. Plasma was collected over 24 hours; cerebrospinal fluid (CSF) and brain tissues including the choroid plexus (CP), pineal gland (PG), pituitary gland (PTG), and CA1 region of the hippocampus were collected at midday, when OXA peaks in diurnal species. OXA levels were significantly higher (P &lt; 0.01) in LD compared to SD in the CP (95.83 %), CSF (140.00 %), CA1 (66.70 %), and plasma (38.46 %). Plasma OXA displayed circadian variation in both seasons; daytime levels were 41.38 % higher during SD (P &lt; 0.01) and 17.28 % higher in LD (P &gt; 0.05). No seasonal differences were found in PTG or PG. This study may reveal the role of OXA in mediating or modifying the effects of day length on seasonal physiological processes in sheep. For example, elevated OXA in spring and summer, when forage is abundant, may support energy demands for lactation and reserve accumulation in preparation for winter forage scarcity.</div></div>","PeriodicalId":21758,"journal":{"name":"Small Ruminant Research","volume":"248 ","pages":"Article 107516"},"PeriodicalIF":1.6,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143886542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Supplementation of orally drenched ascorbic acid and injectable α-tocopherol reduces markers of naturally acquired parasites in grazing hair sheep","authors":"Jesus A. Rojas-Reyes ,&nbsp;Taya J. Blad ,&nbsp;Janae S. Bulosan ,&nbsp;Amy S. Wanguba ,&nbsp;Yunuen Bustamante ,&nbsp;Kara J. Thornton ,&nbsp;Jenee S. Odani ,&nbsp;Caleb C. Reichhardt","doi":"10.1016/j.smallrumres.2025.107515","DOIUrl":"10.1016/j.smallrumres.2025.107515","url":null,"abstract":"<div><div>The objective of this study was to evaluate the effects of exogenous vitamin E and C supplementation in grazing hair sheep on markers of naturally acquired parasites, hypothesizing that supplementing vitamins may be effective as anthelmintics in controlling parasites. Twenty-six lambs and thirty-one ewes were stratified by FAMACHA® scores and placed in one of five treatment groups: (1) control (CON; Lambs: <em>n</em> = 6, Ewes: <em>n</em> = 4), (2) dewormer (DW; Levamed; 0.08 mg/kg; Lambs: <em>n</em> = 5, Ewes: <em>n</em> = 7), (3) vitamin C (VC; Vitamin C;0.56 ml/kg of BW; Lambs: <em>n</em> = 5, Ewes: <em>n</em> = 6), (4) vitamin E (VE; Vitamin E 300; 22 IU/kg of BW; Lambs: <em>n</em> = 6, Ewes: <em>n</em> = 7), and (5) combination of vitamins E and C (E + C; same dosages as vitamins C and E; Lambs: <em>n</em> = 4, Ewes: <em>n</em> = 7). Physiological, parasitology and blood metabolite parameters samples were collected on day 0, 14, 28, 56, and 77. The following parameters and treatments are compared to the CON, unless otherwise mentioned. FAMACHA® scores improved in lambs treated with DW (<em>P</em> = 0.0001), E + C (<em>P</em> = 0.04), VC (<em>P</em> = 0.02), and VE (<em>P</em> = 0.01). Eggs per gram (EPG) decreased in lambs treated with DW (<em>P</em> = 0.001), VC (<em>P</em> = 0.001) and VE (<em>P</em> = 0.008). Alanine transaminase (ALT) decreased (<em>P</em> = 0.04) in lambs treated with DW and VE treated lambs increased (<em>P</em> = 0.02) in ALT compared to the dewormer. Packed cell volume (PCV) in the ewes improved with E + C (<em>P</em> = 0.02) and VE (<em>P</em> = 0.03) compared to DW. The data suggests that vitamin E and C supplementation can be used as a tool to assist in managing parasites in grazing hair sheep.</div></div>","PeriodicalId":21758,"journal":{"name":"Small Ruminant Research","volume":"248 ","pages":"Article 107515"},"PeriodicalIF":1.6,"publicationDate":"2025-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143886543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Automated evaluation of dairy goat body condition and analysis of differences in lumbar features, milk composition and blood biochemical indicators","authors":"Yuning An ,&nbsp;Yifeng Song ,&nbsp;Ziqi Meng ,&nbsp;Yuan Wang ,&nbsp;Buyu Wang ,&nbsp;Na Liu ,&nbsp;Jingwei Qi ,&nbsp;Ming Xu ,&nbsp;Xiaoping An","doi":"10.1016/j.smallrumres.2025.107504","DOIUrl":"10.1016/j.smallrumres.2025.107504","url":null,"abstract":"<div><div>Body condition scoring (BCS) in dairy goats serves as an objective method for quantifying the reserves of body tissues, namely adipose and muscle tissues, and evaluating overall health. Recognized as a dependable and feasible welfare indicator, BCS is crucial for managing animal health. This study introduced an automated BCS model for dairy goats, leveraging computer vision and deep learning via the YOLO v5 algorithm. The model distinguished waist phenotypic characteristics, analyzed milk quality, and assessed blood biochemical indices across different body conditions. Demonstrating high precision, the model achieved Precision (<em>P</em>), Recall (<em>R</em>), and <em>F1</em> scores of 78.5 %, 82.0 % and 81.7 %, respectively. It effectively identified underweight, moderate, and overweight groups with identification rates of 85.2 %, 79 %and 71.2 % respectively, and maintained a deviation rate from manual assessments of ≤ 10 %. Notably, the waist region's grayscale parameters and brightness levels correlated positively with body condition scores, while the depth of indentation exhibited a negative correlation. Milk yield showed no significant variation (3–4 kg), but milk protein content was highest in the average condition group. Lipid and liver metabolism markers varied significantly with body condition, underscoring physiological impacts. This model not only confirmed the robustness of YOLO v5 for animal welfare assessment but also early intervention strategies are used in the management of dairy goats, in line with the principles of precision animal husbandry, particularly beneficial during the critical mid-lactation period. This work underscored the significant potential of integrating advanced technologies into everyday agricultural practices to enhance animal welfare and farm management.</div></div>","PeriodicalId":21758,"journal":{"name":"Small Ruminant Research","volume":"248 ","pages":"Article 107504"},"PeriodicalIF":1.6,"publicationDate":"2025-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143904388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Variation due to additive, dominance and imprinting genetic effects in body weight gain of Baluchi sheep","authors":"Farhad Ghafouri-Kesbi ,&nbsp;Mohsen Gholizadeh","doi":"10.1016/j.smallrumres.2025.107505","DOIUrl":"10.1016/j.smallrumres.2025.107505","url":null,"abstract":"&lt;div&gt;&lt;div&gt;The aim was to estimate relative contribution of additive, dominance and imprinting genetic effects to the phenotypic variation of body weight gain in different growth phases, namely from birth to weaning (BWGa), weaning to 9 months of age (BWGb) and weaning to 12 months of age (BWGc) in Baluchi sheep. This was done in a two-step process. In the first step, each trait was analysed with 12 different animal models which included different combinations of additive genetic, dominance genetic and maternal effects. The best model (Model &lt;strong&gt;I&lt;/strong&gt;) was selected with Akaike Information Criterion (&lt;strong&gt;AIC&lt;/strong&gt;). In the second step, three additional models were fitted by adding maternal imprinting, paternal imprinting, or both (models 13–15) to the Model &lt;strong&gt;I&lt;/strong&gt;. Predictive ability of models was measured using the mean squared error of prediction (MSE) and Pearson's correlation coefficient between the real and predicted values of observations (r(&lt;span&gt;&lt;math&gt;&lt;mi&gt;y&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt;,&lt;span&gt;&lt;math&gt;&lt;mover&gt;&lt;mrow&gt;&lt;mi&gt;y&lt;/mi&gt;&lt;/mrow&gt;&lt;mo&gt;ˆ&lt;/mo&gt;&lt;/mover&gt;&lt;/math&gt;&lt;/span&gt;)). Correlations between traits were estimated using bi-variate analyses. In the first step, for all traits studied, including dominance genetic effects in the model resulted to a significantly better data fit and enhanced predictive ability of the model (higher r(&lt;span&gt;&lt;math&gt;&lt;mi&gt;y&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt;,&lt;span&gt;&lt;math&gt;&lt;mover&gt;&lt;mrow&gt;&lt;mi&gt;y&lt;/mi&gt;&lt;/mrow&gt;&lt;mo&gt;ˆ&lt;/mo&gt;&lt;/mover&gt;&lt;/math&gt;&lt;/span&gt;) and lower MSE). Also it resulted to a significant decrease in the residual variance up to 24 %. However, accounting for dominance genetic effects, significantly increased the computing time and required memory. In the second step, for BWGa, adding maternal imprinting effects to the model &lt;strong&gt;I&lt;/strong&gt; resulted to increase in the likelihood and predictive ability of the model as well as 40 % decrease in the additive genetic variance. Estimates of dominance heritability (&lt;span&gt;&lt;math&gt;&lt;msubsup&gt;&lt;mrow&gt;&lt;mi&gt;h&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;d&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/msubsup&gt;&lt;/math&gt;&lt;/span&gt;), were 0.19, 0.15 and 0.20 for BWGa, BWGb and BWGc, respectively. Additive heritability (&lt;span&gt;&lt;math&gt;&lt;msubsup&gt;&lt;mrow&gt;&lt;mi&gt;h&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/msubsup&gt;&lt;/math&gt;&lt;/span&gt;), were 0.08, 0.08 and 0.07 for BWGa, BWGb and BWGc, respectively. For BWGa, maternal imprinting heritability (&lt;span&gt;&lt;math&gt;&lt;msubsup&gt;&lt;mrow&gt;&lt;mi&gt;h&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;mi&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/msubsup&gt;&lt;/math&gt;&lt;/span&gt;) was 0.08. While additive genetic correlations were all positive and high, dominance genetic correlation between BWGb and BWGc was positively high and between other pairs of traits was negatively high. For all traits studied, correlation between breeding values obtained from models with/without dominance genetic effect was close to unity (0.99) but between breeding values obtained from models with/without imprinting effects deviated from unity (0.85 for BWGa) indicating change in ranking of top","PeriodicalId":21758,"journal":{"name":"Small Ruminant Research","volume":"248 ","pages":"Article 107505"},"PeriodicalIF":1.6,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143881366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}