Livestock Science最新文献

{"title":"Fast across all distances: Genetic parameters and selection for racing time in Quarter Horses using a random regression model","authors":"Thiago G.B. Franco ,&nbsp;Annaiza B. Bignardi ,&nbsp;Ricardo A.S. Faria ,&nbsp;Antônio R. Silva ,&nbsp;Josineudson A.II V. Silva ,&nbsp;Mário L. Santana","doi":"10.1016/j.livsci.2025.105653","DOIUrl":"10.1016/j.livsci.2025.105653","url":null,"abstract":"<div><div>The Quarter Horse, renowned for its exceptional speed and versatility, is one of the most prominent breeds in short-distance racing. Despite this, there is a lack of studies on the performance of these animals across different distances, particularly using an approach that accounts for the longitudinal nature of racing performance. Our objectives in this study were to apply a random regression model (RRM) to estimate genetic parameters for racing time (RT) at different distances in Brazilian Quarter Horses and to examine the genetic trends in performance over recent years. A total of 21,173 records from 4,482 horses that competed in races of varying distances were used. The heritability and repeatability estimates ranged from 0.05 ± 0.02 to 0.22 ± 0.03 and from 0.17 ± 0.02 to 0.48 ± 0.04 for shorter to longer distances, respectively. The genetic correlations for RT between different race distances were very high and positive, with the lowest correlation observed between the 275 m and 402 m distances (0.84 ± 0.12). The RRM effectively identified animals with stable and variable genetic merit across distances. Genetic trends for RT were favorable across races of all distances. Selecting for RT in longer distances may enhance speed across all distances. This longitudinal evaluation proved effective for analyzing performance, revealing important genetic progress in the Brazilian Quarter Horse population, particularly in 402 m races.</div></div>","PeriodicalId":18152,"journal":{"name":"Livestock Science","volume":"293 ","pages":"Article 105653"},"PeriodicalIF":1.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143342765","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":"She-camel (Camelus Dromedarius) reproductive status and biochemical blood parameters assay in extensive breeding in southern Algeria","authors":"Rabah Kelanemer ,&nbsp;Djallel Adel ,&nbsp;Bachir Medrouh ,&nbsp;Redha Belala ,&nbsp;Sabrina Sellali ,&nbsp;Amina Saidi ,&nbsp;Ammar Kalem ,&nbsp;Yasmine Rahmoune ,&nbsp;Naima Dellal ,&nbsp;Said Fettata ,&nbsp;Nassim Moula ,&nbsp;Hocine Ziam","doi":"10.1016/j.livsci.2025.105646","DOIUrl":"10.1016/j.livsci.2025.105646","url":null,"abstract":"<div><div>Despite its importance to social and economic life in arid and semi-arid regions of Algeria, the dromedary camels has received little scientific attention in our country. This research focuses on two aspects of this animal in its natural environment. An individual monitoring of 14 reproductive parameters in 110 breeding camelids over 18 months and a single analysis of blood biochemical parameters in 212 animals was performed. The results reveal that the camel breeding season lasts from October to June, with an oestrus or “heat” duration (7.7 ± 1.4 days), mating duration (25±10 min), gestation duration (377 ± 9.4 days), labour duration (37.7 ± 15 min), delivery duration (37.9 ± 10 min), duration of return to oestrus after parturition (30.3 ± 11.7 days), average duration between parturition and fertilising oestrus (216 ± 137.7 days), rate of females returning to oestrus after parturition (77.2 %), fertility rate (54.11±10.6 %). Our findings for blood biochemical parameters show average glycemia (1.21 ± 0.04 g/l), proteinemia (63.8 ± 73 g/l), uremia (432.54 ± 17.4 mg/l), triglyceride levels (487.66 ± 86 mg/l), cholesterol (318.7 ± 32 mg/l), lipids (3 ± 0.31 g/l), calcium (87.45 ± 3.7 mg/l), phosphorus (46.5 ± 3.95 mg/l) and magnesium (23.47 ± 2.25 mg/l). Statistical analysis indicates that age, gender, and production status significantly affected most of blood biochemical parameters (<em>p</em> ≤ 0.001). The findings were compared to those of other authors from other countries. Research, understanding, and improvement of the dromedary camels breeding system remain crucial in Algeria.</div></div>","PeriodicalId":18152,"journal":{"name":"Livestock Science","volume":"292 ","pages":"Article 105646"},"PeriodicalIF":1.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143135604","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":"Substituting barley with soya bean hulls in the concentrate offered to beef cattle as a supplement to grass silage or ad libitum: Intake, feed efficiency, carcass and selected meat quality traits","authors":"M. McGee ,&nbsp;C. Lenehan ,&nbsp;D. Magee ,&nbsp;E.G. O'Riordan ,&nbsp;A.K. Kelly ,&nbsp;A.P. Moloney","doi":"10.1016/j.livsci.2024.105634","DOIUrl":"10.1016/j.livsci.2024.105634","url":null,"abstract":"<div><div>There is growing interest in human-inedible by-product feed ingredients as a substitute to cereals in concentrate feedstuffs for beef cattle. Three experiments were carried out to determine the effects of complete or partial replacement of rolled barley with soya bean hulls (SH) in the concentrate, offered as a supplement to perennial rye-grass dominant grass silage or <em>ad libitum</em>, on intake, rumen fermentation, feed efficiency, carcass characteristics and selected meat quality traits of beef cattle. The control concentrates were based on (g/kg fresh weight) rolled barley (860 g/kg), soya bean meal (60 g/kg), cane molasses (50 g/kg), and minerals and vitamins (25 g/kg), and in the treatment concentrates, barley (+ soya bean meal) was replaced with SH. Inclusion levels of SH (g/kg fresh weight) were; SH- 0 and 933 (Experiment 1); SH- 0, 200, 400, 600 and 800 (Experiments 2a and 2b). Concentrates were offered to growing cattle as a supplement to grass silage in Experiment 1 for 90 days and in Experiment 2a for 71 days (1.7 and 3.0 kg dry matter (DM) daily, respectively), and in Experiment 2b <em>ad libitum</em> to finishing cattle for 70 days. In Experiment 1, inclusion of SH in the concentrate supplement had no effect on total DM intake, live weight gain (LWG), feed conversion ratio (FCR) or on the acetate-to-propionate ratio in rumen fluid. In Experiment 2a, there was a linear decrease in LWG and a linear increase in FCR as the level of SH inclusion in the concentrate increased. Total DM intake did not differ between concentrate treatments. In Experiment 2b, there was a linear increase in DM intake and FCR, and a linear decrease in LWG, slaughter weight, carcass weight and carcass fat score as the level of SH inclusion in the concentrate increased. In Experiment 2b, increasing the inclusion level of SH in the concentrate, did not affect <em>M. longissimus</em> muscle colour, linearly increased the proportion of total saturated fatty acids, vaccenic, linolenic and conjugated linoleic acids, and linearly decreased the proportion of monounsaturated fatty acids in <em>M. longissimus</em> muscle. In conclusion, SH and rolled barley had equivalent feeding value for beef cattle at low concentrate supplementation levels to grass silage, but barley was superior to SH at moderate concentrate supplementation levels, and particularly in high-concentrate finishing diets. Soya bean hull inclusion had little effect on fat and muscle colour but improved the fatty acid composition of <em>M. longissimus</em> muscle in terms of human nutrition.</div></div>","PeriodicalId":18152,"journal":{"name":"Livestock Science","volume":"292 ","pages":"Article 105634"},"PeriodicalIF":1.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143095968","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":"Changes in the relationship between an endangered cattle breed and its mainstream sister breed over time","authors":"H. Wilmot ,&nbsp;N. Gengler ,&nbsp;J. Bormann ,&nbsp;M.P.L. Calus","doi":"10.1016/j.livsci.2025.105652","DOIUrl":"10.1016/j.livsci.2025.105652","url":null,"abstract":"<div><div>Because of lack of pedigree records, the history of the Red-Pied of the Ösling (RPO) breed, which is an endangered local red-pied cattle breed from Luxembourg, is not really known. However, it is assumed that there has been exchanges between the RPO and the Meuse-Rhine-Yssel (MRY), another red-pied cattle breed from The Netherlands. To validate this assumption, we estimated the changes in the relationships between the RPO and MRY breeds over time by the definition of cohorts with different birthdates in the MRY breed. The fixation indexes between the RPO breed and the different MRY cohorts, as well as a principal component analysis, showed that the RPO breed was more related to the oldest MRY animals, born before 1990, and to the youngest MRY animals, born after 2009. This confirmed the <em>a priori</em> known pattern of importation of MRY animals to the RPO population over time. Based on results obtained in a genomic relationship matrix and on the proportion of opposing homozygotes, we could infer sire-offspring relationships between an MRY sire and three RPO animals. To complete the pedigree of RPO animals even further and optimize exchanges between the MRY and RPO breeds, it would be interesting to have access to more MRY genotypes.</div></div>","PeriodicalId":18152,"journal":{"name":"Livestock Science","volume":"293 ","pages":"Article 105652"},"PeriodicalIF":1.8,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143155605","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":"A simple laboratory method for estimating the standardised precaecal digestible crude protein in pig feeds","authors":"Valérie Schumacher ,&nbsp;Markus Rodehutscord ,&nbsp;Karl-Heinz Südekum ,&nbsp;Saskia Kehraus","doi":"10.1016/j.livsci.2025.105651","DOIUrl":"10.1016/j.livsci.2025.105651","url":null,"abstract":"<div><div>Adequate protein supply for pigs to sustain performance and animal health can be determined <em>in vivo</em> from standardised precaecal digestible (pcd) crude protein (pcdCP). Until now, only time-consuming methods are available to estimate pcdCP from laboratory measurements without <em>in vivo</em> experiments. Therefore, the objective was to develop and establish a rapid laboratory method for estimating pcdCP based on the determination of neutral-detergent-insoluble or acid-detergent-insoluble crude protein (NDICP, ADICP). The CP was determined for cereal grains on the neutral detergent residue and for all protein feeds on the acid detergent residue, because N compounds such as Maillard products or N bound to tannin or in phytate complexes are retained in the acid detergent-insoluble fraction. A unique, large sample pool of 82 feed ingredients (cereal grains, differently heat-treated legume grains) was available on which <em>in vivo</em> pcdCP were determined in cannulated pigs. Crude protein (N ∙ 6.25) was determined in feed ingredients and in their ND or AD residues. The concentrations of ND- and AD-soluble CP (NDSCP, ADSCP) were calculated by difference. For the estimation of the concentrations of <em>in vivo</em> pcdCP for the entire dataset, a linear relationship was established between the concentrations of NDSCP or ADSCP and the <em>in vivo</em> pcdCP: <em>y</em> = 0.8640 (standard error [SE] 0.019) x - 13.37 (SE 7.479), where y represents the <em>in vivo</em> pcdCP (g/kg dry matter) and x represents the NDSCP (cereal grains) or ADSCP (protein feeds) value (g/kg dry matter). The coefficient of determination (R²) of this equation was 0.962. A validation with literature values showed a good fit of the equation to an independent data set (<em>n</em> = 20; R² = 0.955). This study shows that based on chemical analysis alone, namely determination of NDICP and ADICP, from which NDSCP and ADSCP are calculated, <em>in vivo</em> pcdCP values can be estimated with a standardised and rapid laboratory method.</div></div>","PeriodicalId":18152,"journal":{"name":"Livestock Science","volume":"293 ","pages":"Article 105651"},"PeriodicalIF":1.8,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143342764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Estimating daily fat percentage from single samples in herds with automatic milking system using a regression model","authors":"Julia S. Gerke ,&nbsp;Martin Kammer ,&nbsp;Andreas Werner ,&nbsp;Ralf Köstler ,&nbsp;Jörg Piepenburg ,&nbsp;Martin Mayerhofer ,&nbsp;Florian Grandl ,&nbsp;Jürgen Duda","doi":"10.1016/j.livsci.2025.105649","DOIUrl":"10.1016/j.livsci.2025.105649","url":null,"abstract":"<div><div>Constant access to the automatic milking system (AMS) leads to varying milking frequency of cows and subsequently varying milking interval lengths (MI) and milk yield (MY) of single milkings. This influences milk production and can result in variable milk composition in individual milkings during the day.</div><div>In this study, different effects of animal and milking frequency associated characteristics on the milk components fat and protein from herds milked with AMS were explored and analyzed with respect to their influence on daily content. From this, a new regression model was developed to enable the estimation of daily fat percentage from single sampled milkings on test day. Collectively, 909,922 test day records from 176,926 cows in Germany and Austria milked two to three times within 24 h with AMS were assembled. As the complex process of fat production in the udder is notably affected by MI and MY, common regression models address this issue by mainly relying on fat%, MY and MI of two preceding milkings. The new regression model increases the number of included preceding milkings up to four covering a timespan of &gt;24 h. Moreover, the model is complemented by lactation stage, parity, and daytime of the sampled milking. Its performance was compared to those of two regression models from literature. With a root mean squared error of 0.275, a mean absolute error of 0.195 and R² = 0.816 the new model outperformed these reference models. For 62.6 % of test day records, the developed model estimated a more precise daily fat content than the measured fat content from a single milking.</div><div>Therefore, this model is an adequate solution for estimating the daily fat content for AMS herds, which are not able to take more than one sample on test day.</div></div>","PeriodicalId":18152,"journal":{"name":"Livestock Science","volume":"293 ","pages":"Article 105649"},"PeriodicalIF":1.8,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143155603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Inferring effects of barn emissions, housing conditions and genetics on specific dermatitis digitalis diagnoses in dairy cows","authors":"Niklas Sölzer,&nbsp;Kerstin Brügemann,&nbsp;Petra Engel,&nbsp;Sven König","doi":"10.1016/j.livsci.2025.105650","DOIUrl":"10.1016/j.livsci.2025.105650","url":null,"abstract":"<div><div>The aim of the present study was to infer effects of housing systems, cow phenotypes and genomics on specific stages of the claw disorder dermatitis digitalis (<strong>DD</strong>) of dairy cows kept in compost bedded pack barns (<strong>CBPB</strong>) and conventional cubicle barns (<strong>CCB</strong>) applying structural equation models (<strong>SEM</strong>). Housing system characterisations, herd hygiene status determination and greenhouse gas emission recordings considered 11 farms, whereas 6 farms represented the CBPB system, 2 farms represented the CCB system, and 3 farms “mixed farming” system with CBPB for sub-herd A and CCB for sub-herd B. In these 11 farms, 1,047 Holstein-Friesian and Fleckvieh-Simmental cows (1,611 observations) were phenotyped for the DD stages DD sick, DD acute and DD chronic. Cows from 4 further farms without housing and greenhouse gas emission data were considered for DD phenotyping and SNP genotyping, implying the availability of 2,980 DD observations from 1,710 cows for genomic studies of DD traits. In a first step, generalized linear mixed models were applied to identify the most relevant housing characteristics on DD sick, DD acute and DD chronic. Least-squares-means for infection probabilities were generally smaller in CBPB than in CCB. With regard to compost, barn air and barn emission characteristics in CBPB, a bedding temperature in the range &lt; 28°C, a C:N ratio in the bedding material &gt; 21, a pH-value in the bedding material &gt; 8.8, small NH₃ concentrations (&lt; 0.55) in the barn air, as well as small as moderate air humidity, were associated with the highest DD health status. The single-step GWAS indicated similar Manhattan plots for DD sick and DD acute, and respective shared potential candidate genes based on gene annotations from the <em>Bos taurus</em> ARS1.2 genome assembly. Three same SNPs were significantly associated (according to normative significance threshold) with DD acute and DD sick, but no overlaps in this regard were identified for other DD stages. Strong association signals in the Manhattan plots according to strict pBF were identified for DD chronic including three further SNPs, and for DD acute including the SNP <em>Hapmap47993-BTA-56668</em> (HAP) located on BTA 23. These SNPs together with latent variables for the cow DD individuality (<strong>DD indiv</strong>, including phenotypes and estimated breeding values for DD stages), cow productivity before and after a DD diagnosis, and the relevant barn and housing characteristics (as identified via mixed model applications), were simultaneously considered in SEM for DD sick, DD acute and DD chronic. Housing and barn characteristics played a predominant role with regard to infection risks for DD sick and DD acute. In contrast for DD chronic, path coefficients on DD indiv were quite large for DD chronic EBVs, as well as for single SNP effects.</div></div>","PeriodicalId":18152,"journal":{"name":"Livestock Science","volume":"293 ","pages":"Article 105650"},"PeriodicalIF":1.8,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143155604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of a ten-week lactation period on sow and litter performance in organic outdoor production","authors":"T.F. Pedersen ,&nbsp;M. Eskildsen ,&nbsp;A.G. Kongsted","doi":"10.1016/j.livsci.2025.105647","DOIUrl":"10.1016/j.livsci.2025.105647","url":null,"abstract":"<div><div>In recent years the average lactation period for organic pigs reared outdoors has been extended to improve piglet robustness at weaning and to eliminate the need for a separate weaner facility. This study aimed to investigate the performance of outdoor sows and litters after lactation periods of seven and 10 weeks. Twenty litters comprising a total of 251 pigs were assigned to one of two weaning strategies: weaning at seven weeks or weaning at 10 weeks. Post-weaning, the piglets were transferred to outdoor weaner paddocks and monitored until they reached 17 weeks of age. Sows' body weight (BW), back fat thickness (BF), udder, and teat condition were assessed after seven and 10 weeks of lactation. Piglets were weighed at the end of week 7, 10, 14, and 17 post-partum. Sow feed intake was recorded from weeks 8 to 10, while piglets' feed intake was monitored from weeks 8 to 10, 11 to 14, and 15 to 17. There were no changes in sow BF, teat, and udder condition during the three-week extended lactation period (<em>P</em> &gt; 0.05). Sows exhibited an increase in BW by 8.8 kg during the three-week extended lactation period (<em>P</em> &lt; 0.01). The weaning strategy did not affect piglets' average daily gain (ADG), feed intake (ADFI), or feed conversion ratio (FCR), in terms of kg feed per kg gain, from week 10 to 14, as well as ADG and ADFI from week 15 to 17 (<em>P</em> &gt; 0.05). Overall, pigs per litter after 17 weeks and total gain (sow and pigs) from week 8 to 17 did not differ between weaning strategies (<em>P</em> &gt; 0.05). When including feed use for sows, piglets, and weaners, overall FCR in terms of kg feed per kg gain was numerically higher for litters weaned after 10 weeks of lactation (<em>P</em> <em>=</em> 0.11). However, overall FCR in terms of kg crude protein (CP) and metabolizable energy (ME) per kg gain did not differ between weaning strategies (<em>P</em> &gt; 0.05). In conclusion, extended lactation had no detrimental effects on outdoor sows’ body condition and udder condition at weaning. On the other hand, when the piglets are weaned in outdoor conditions, in small group sizes and sorted according to size, weaning at seven or 10 weeks of age seems to be equally suitable strategies to obtain good pig health and high growth rates until 17 weeks of age.</div></div>","PeriodicalId":18152,"journal":{"name":"Livestock Science","volume":"293 ","pages":"Article 105647"},"PeriodicalIF":1.8,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143155685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of oregano essential oils and probiotics supplementation on growth performance, immunity, antioxidant status, intestinal microbiota, and gene expression in broilers experimentally infected with Eimeria","authors":"Ahmed M. Elbaz ,&nbsp;Eman S. Ashmawy ,&nbsp;Disouky M. Mourad ,&nbsp;Shimaa A. Amin ,&nbsp;Eman Kamel M. Khalfallah ,&nbsp;Zangabel S. Mohamed","doi":"10.1016/j.livsci.2024.105622","DOIUrl":"10.1016/j.livsci.2024.105622","url":null,"abstract":"<div><div>The poultry industry has several disease challenges; coccidiosis is considered one of the most dangerous parasitic diseases. Six-hundred Ross 308 male broiler chicks (average initial body weight 41.5 g) were allocated to six groups: negative control uninfected (NCO); positive control infected with <em>Eimeria</em> (PCO); or positive control supplemented with diclazuril (0.2 g/kg diet, DIC); two-strains probiotic (2 g/ kg diet, PRO); oregano essential oil (300 mg/ kg diet, OEO); a combination of 2 g probiotic and 300 mg oregano essential oil (POE). At day 15, all groups except NCO were inoculated via oral gavage with oocysts of mixed <em>Eimeria</em> spp. Our results indicated that the infected chickens with mixed <em>Eimeria</em> (PCO) exhibited lower growth performance, higher mortality rate, and increased oocyst shedding (<em>P</em>&lt; 0.05), in addition to deterioration of immune-oxidative status in broilers on 35 d. On the contrary, <em>Eimeria</em>-infected chickens fed on a diet supplemented with DIC, PRO, OEO, and POE showed improved growth performance (<em>P</em>&lt; 0.05) and decreased mortality and oocyst shedding. Moreover, feeding chickens on POE enhanced body weight gain, feed conversion ratio, crude protein digestibility, and dressing. Furthermore, POE supplements supported immunity and antioxidant status by increasing IgA, IgG, IL-10, and SOD levels (<em>P</em>&lt; 0.05) and reducing IL-6 and MDA levels. Additionally, adding POE altered the gut microbiota structure via an increasing <em>Lactobacillus</em> count and decreasing <em>C. perfringens, E. coli</em>, and <em>Coliforms</em> count. Notably, POE supplements also reduced oocyst shedding and lesion scores. Moreover, the up-regulated nutrient transporters, including the expressions of cationic amino acid transporter-1 (CAT-1) and mucin-2 (MUC-2) were up-regulated (<em>P</em> &lt; 0.05) in the POE group compared to other groups. Therefore, our study concluded that a combination of probiotics and oregano essential oils was preferred as an effective choice for protecting broilers against coccidiosis.</div></div>","PeriodicalId":18152,"journal":{"name":"Livestock Science","volume":"291 ","pages":"Article 105622"},"PeriodicalIF":1.8,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143170373","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 different arginine-to-lysine ratios and guanidinoacetic acid supplementation on the growth performance, carcass characteristics and breast myopathies in broiler chickens","authors":"Edwin Westreicher-Kristen ,&nbsp;Roger Davin ,&nbsp;Piero Agostini ,&nbsp;Behnam Saremi","doi":"10.1016/j.livsci.2024.105624","DOIUrl":"10.1016/j.livsci.2024.105624","url":null,"abstract":"<div><div>The aim of the study was to evaluate the effect of increasing the digestible arginine-to-lysine ratio (dig Arg:Lys) (Experiment 1), and to evaluate the Arg sparing effect of guanidinoacetic acid (GAA) (Experiment 2) on growth performance, carcass composition and breast myopathies in broiler chickens. In experiment (Exp) 1, a total of 672 male Ross 308 birds were assigned to 4 experimental groups provided in a 4-phase feeding scheme. The Control treatment had a dig Arg to Lys ratio (Arg:Lys) of 1.06, 1.06, 1.07 and 1.08 in starter, grower I, grower II and finisher diets, respectively; the other three experimental treatments had a dig Arg:Lys ratio of 1.15, 1.25 and 1.35 across all feeding phases by adding L-Arg to Control diets. In Exp 2, 504 male Ross 308 birds were fed using the same feeding scheme and assigned to 3 experimental groups: the Control diet had a dig Arg:Lys ratio of 1.05, and the other two treatments were supplemented with 0.6 g/kg GAA using two different dig Arg equivalency: 77% (GAA77) or 149% (GAA149). In Exp 1, body weight (BW), BW gain (BWG) and feed conversion ratio (FCR) were affected in a quadratic fashion (<em>P</em> ≤ 0.03 for all) at cumulative phases 0-10 and 0-20 d when increasing the dig Arg:Lys ratio. In these phases, the highest BW, BWG and best FCR were obtained with the highest dig Arg:Lys ratio (1.35). The latter effects were not observed for the phases 0-30 and 0-44 d. In Exp 2, the replacement of Arg by GAA did not affect the productive performance (<em>P</em> &gt; 0.13) in the phases 0-20, 0-30 and 0-44 d, but GAA77 impaired FCR compared to control (<em>P</em> = 0.05) in phase 0-10 d. For carcass traits, only breast yield was increased in both GAA groups compared to Control (<em>P</em> = 0.01) at 35 d, and breast meat redness (a*) was decreased (<em>P</em> = 0.01) with GAA77 compared to CON. Skin scratches, breast myopathies, litter score and foot pad dermatitis were not affected by dietary treatments in any of the 2 Exps. In conclusion, increasing the dig Arg:Lys ratio to 1.35 has a positive effect on growth performance from 0-20 d of age without affecting breast myopathies incidence. Dietary supplementation of GAA could replace 77% of Arg without affecting performance parameters in broilers.</div></div>","PeriodicalId":18152,"journal":{"name":"Livestock Science","volume":"291 ","pages":"Article 105624"},"PeriodicalIF":1.8,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143170372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}