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9 páginas, 3 figuras, 2 tablas., This study evaluated the influence of a temporary nutritional protein restriction (NPR) performed, under commercial conditions, in prepubertal female lambs on first lactation milk production traits and the inflammatory response triggered by an inflammatory challenge of the. From 40 Assaf female lambs, we defined a control group (C n = 20), which received a standard diet for replacement lambs and the NPR group (n = 20), which received the same diet but without soybean meal between 3 and 5 months of age. About 150 days after lambing, 24 of these ewes (13 NPR, 11C) were subjected to an intramammary infusion of E. coli lipopolysaccharide (LPS). Our dynamic study identified indicator traits of local (SCC) and systemic (rectal Ta, IL-6, CXCL8, IL-10, IL-36RA, VEGF-A) response to the LPS challenge. The NPR did not show significant effects on milk production traits and did not affect the SCC and rectal Ta after the LPS challenge. However, the NPR had a significant influence on 8 of the 14 plasma biomarkers analysed, in all the cases with higher relative values in the C group. The effects observed on VEGF-A (involved in vasculogenesis during mammary gland development and vascular permeability) and IL-10 (a regulatory cytokine classically known by its anti-inflammatory action) are the most remarkable to explain the differences found between groups. Whereas further studies should be undertaken to confirm these results, our findings are of interest considering the current concern about the future world's demand for protein and the need for animal production systems to evolve toward sustainability., The nutritional and inflammatory challenge experiments and the sample collection described in this study were funded by the SMARTER project through the Horizon 2020 research and innovation program of the European Commission (Grant Agreement No. 772787). The cytokine/interleukine panel analyses were funded by the Spanish national project EPIMILKSHEEP (Ref. RTI2018–093535-B-I00), funded by the Spanish Ministry of Science and Innovation.

SUPPLEMENTARY MATERIAL - Please download it using the following link: http://dx.doi.org/10.20350/digitalCSIC/13779 (OPEN ACCESS), This work was supported by the Junta de Castilla y León (JCyL, Spain; project CSI276P18). P. G. Toral benefited from a Ramón y Cajal research contract from the Spanish Ministry of Economy and Competitiveness (MINECO; RYC-2015-17230) and C. Fernández-Díez from a postdoctoral research contract from JCyL. Co-funding by the European Regional Development Fund (ERDF/FEDER) and the European Social Fund (ESF) is also acknowledged.

12 páginas, 4 tablas., Small ruminants are susceptible to milk fat depres-sion (MFD) induced by marine lipid supplementation. However, as observed in dairy cows, there is wide in-dividual variation in the response to MFD-inducing diets, which may be due to individual differences in ruminal processes. Therefore, we compared the rumi-nal responses of goats and sheep with varying degrees of MFD extent to improve our understanding of this complex syndrome. Our specific aims were to attempt to elucidate whether pre-existing variations in ruminal fermentation and biohydrogenation determine a higher tolerance or susceptibility to MFD, and whether the severity of MFD depends exclusively on the response to the diet. The trial was conducted with 25 does and 23 ewes fed a basal diet without lipid supplementation for 3 wk (control period). Then, 2% fish oil (FO) was added to the same diet for 5 additional weeks (MFD period). Based on the extent of the elicited MFD (i.e., the percentage variation between milk fat concentra-tions recorded at the end of the control and MFD periods), the 5 most responsive (RESPON+) and the 5 least responsive (RESPON−) animals were selected within each species. On the last day of each period, ruminal fluid samples were collected to examine fer-mentation parameters and fatty acid profiles. In gen-eral, the individual degree of MFD in sheep and goats did not seem to be predetermined by traits related to ruminal fermentation and biohydrogenation, including fatty acids that may serve as biomarkers of microorgan-isms. Regarding differences in the response to FO, the results suggest no link between MFD susceptibility and concentration of biohydrogenation intermediates such as trans-10-containing C18, C20, and C22 metabolites.The explanation for individual responses based on a shortage of ruminal acetate and 18:0 for mammary uptake also seems to be dismissed, based on the lack of variation in these compounds between RESPON+ and RESPON−. However, the concentration of unsaturated fatty acids provided by FO (e.g., cis-9 16:1, cis-11 18:1, and 20:5n-3) was higher in the rumen of RESPON+ than RESPON− ewes and does. Thus, although further research is needed, the extent of biohydrogenation of these fatty acids might be associated with tolerance or susceptibility to MFD., This work was supported by the Spanish Research State Agency (Agencia Estatal de Investigación) and the European Regional Development Fund (projects AGL2017-87812-R, MINECO/AEI/FEDER, EU and PID2020-113441RB-I00, MCIN/AEI). A. Della Badia benefited from an FPI predoctoral contract, co-funded by the European Social Fund (PRE2018-086174, MCIU/AEI/FSE, EU). The authors thank L. Barrios (Biostatistics Department, CSIC; Madrid, Spain) for her helpful assistance with statistical analysis. The au-thors have not stated any conflicts of interest.

Although positive psychology interventions increase well-being and reduce depression, little is known about whether they facilitate a reorganization of the connections between psychological element...

El presente artículo da a conocer una pintura ridícula de Francisco Barrera, que ayuda a contextualizar otro tipo de obras anónimas de similar factura, y comprender mejor las estrategias comerciales que algunos artistas siguieron en el Madrid de la primera mitad del siglo XVII.

Isotopic tracers are used to directly quantify the effect of mammary Δ9-desaturation on milk fatty acid (FA) composition, but very few studies have applied this method to measuring the endogenous synthesis of rumenic acid (RA; cis-9,trans-11 conjugated linoleic acid) in cows and goats, and no publications exist in ewes. In sheep, knowledge about the contribution of stearoyl-coenzyme A desaturase (SCD) to milk FA secretion is derived mostly from indirect estimates based on inhibition of the enzyme by oral administration of cobalt, a cost-effective method that has not been validated to date. To fill both gaps, we conducted an isotopic tracer assay in sheep to quantify the proportion of endogenous RA in milk for the first time in this species. We then compared the results with estimates derived from a Co administration assay performed on the same animals. First, 5 lactating ewes received an intravenous injection of 200 mg of [1-13C]trans-11 18:1 (vaccenic acid, VA), the precursor for RA production by SCD activity. At -24, -15, 0, 9, 24, 33, 48, 57, 72, 81, and 96 h post-injection, we recorded milk yield and collected milk samples to examine fat concentration and FA profile. We conducted compound-specific isotope analysis of VA and RA by gas chromatography-combustion isotope ratio mass spectrometry. Afterward, in the Co administration assay, ewes received a daily dose of 7 mg of Co/kg of body weight for 5 d. We analyzed milk samples for composition before and on the last days of cobalt dosing. On average, 17% of the injected amount of [1-13C]VA was transferred to milk within 96 h post-injection, and up to 29% of the VA taken up by the mammary gland was desaturated to milk RA. Under our conditions, the mean proportion of this conjugated linoleic acid isomer deriving from Δ9-desaturation represented 82 to 90% of the amount secreted in milk. However, the proportion estimated in the Co assay with calculations based on individual FA concentrations was lower (on average, 46%). When we calculated the same estimates based on changes in Δ9-desaturation ratios after Co dosing, the higher values of endogenous RA (75%) did not differ from the results of the isotopic tracer assay. Nevertheless, correlation analysis between the results obtained through [1-13C]VA or Co administration revealed no significant relationship, which would prevent acceptance of the latter as a reliable alternative to isotopic labeling to examine mammary Δ9-desaturation in dairy ewes.

Resumen Objetivo Se describe el caso clinico de una mujer, C.G, de 22 anos con trastorno de ansiedad generalizada, con el proposito de evaluar el efecto del Protocolo Unificado para el Tratamiento Transdiagnostico de los trastornos emocionales para reducir la ansiedad. Metodo Se trata de un diseno de caso unico, pre- postramiento. Los instrumentos de evaluacion utilizados para el diagnostico y posterior establecimiento del tratamiento fueron el Inventario de Ansiedad Estado-Rasgo (Spielberger, Gorusch, y Lushene), la Escala de Valoracion de la Ansiedad de Hamilton (Hamilton, 1959; Lobo et al., 2002), el Cuestionario de Preocupaciones del Estado de Pensilvania (Comeche, Diaz, y Vallejo, 1995; Meyer, Miller, Metzger y Borkovec, 1990), y el Inventario de Depresion de Beck (Beck, Steer, y Brown, 2011). La intervencion fue la aplicacion del Protocolo Unificado para el Tratamiento Transdiagnostico de los trastornos emocionales (Barlow et al., 2015) en 23 sesiones de 50 minutos. Finalmente se volvio a evaluar con los mismos instrumentos previos al tratamiento. Resultados Conforme a las pruebas postratamiento, en concreto Cuestionario de Preocupaciones del Estado de Pensilvania (Comeche, Diaz, y Vallejo, 1995; Meyer, Miller, Metzger y Borkovec, 1990), C.G. ya no reune los criterios ni alcanza la puntuacion (de 77 a 40) para el diagnostico de trastorno de ansiedad generalizada. Conclusiones Tras el tratamiento, se observa una clara mejoria con una reduccion significativa en el numero de anticipaciones, lo que confirma la eficacia del tratamiento transdiagnostico para este caso.

9 páginas, 2 figuras., Milk fat depression (MFD) is characterized by a reduction in the content of milk fat, presumably caused by the anti-lipogenic effects of rumen biohydrogenation intermediates, such as trans-10 cis-12 conjugated linoleic acid (CLA). In this study, RNA-Seq technology was used to help elucidate the mammary responses involved in CLA-induced MFD in lactating ewes. To this end, we compared the milk somatic cell transcriptome of ewes suffering from CLA-induced MFD with control ewes (i.e., those without MFD), as well as with ewes fed a diet supplemented with fish oil (FO-MFD) that we previously reported affects the mammary transcriptome. In the differential expression analysis between CLA-MFD and controls, we identified 1,524 differentially expressed genes (DEGs), whereas 653 were detected between CLA- and FO-MFD groups. Although this article focuses on lipid metabolism, CLA affected the expression of many genes related to other biological processes, especially immunity. Among the 55 genes shared by both MFD conditions, some genes linked to fatty acid synthesis, such as ACACA, AACS, ACSS2, or ACSS3, were downregulated. In addition, this study provides a list of candidate genes that are not usually considered in the nutrigenomics of MFD but that may act as key regulators of this syndrome in dairy ewes., This work was supported by the Spanish Ministry of Economy and Competitiveness (MINECO; AGL2014-54587-R and AGL2015-66035-R projects, co-funded by the European Regional Development Fund). B.G.G and P.G.T. benefited from two Ramon y Cajal postdoctoral research contracts from MINECO (RYC-2012-10230 and RYC-2015-17230, respectively, co-funded by the European Social Fund).

11 páginas, 3 tablas, 3 figuras., The basis for marine lipid-induced milk fat depression (MFD) has not been stablished yet, but recent reports suggest the putative contribution of shifts in the ruminal metabolism of α-linolenic acid (ALA). To test this hypothesis, an isotopic tracer approach was used in batch cultures of rumen microorganisms with inoculum collected from cannulated ewes fed either a total mixed ration without lipid supplementation (control inoculum) or the same diet supplemented with 2% of fish oil, which is known to cause MFD in lactating sheep (FO-MFD inoculum). The [1-13C]ALA was added at a dose of 1% of incubated dry matter and the proportions of 13C-labeled fatty acids (FA) were examined after 24 h of incubation, using complementary gas chromatography and gas chromatography-combustion isotope ratio mass spectrometry (GC-C-IRMS) analyses. Expected differences in FA profiles were confirmed between control and FO-MFD inocula (e.g., large decreases in 18:0 and increases in most 18:1 and 18:2 intermediates, particularly trans isomers, to fish oil supply). The BH of 13ALA was extensive and yielded multiple metabolites, with a total of 48 chromatographic peaks showing 13C enrichment, regardless of the inoculum type. However, although ALA was biohydrogenated through common pathways under standard or MFD conditions, large changes in the accumulation of 13C-labeled FA suggest important differences in the relative contribution of each specific route. First, increased accumulation of trans-11-containing FA in FO-MFD incubations was accompanied by a general repression of the trans-13/14 pathway (supported by lower trans-13+14 18:1 or trans-11 trans-13 18:2 proportions), together with a lower production of cis FA (e.g., cis-9, -12 and -15 18:1 and some cis,cis 18:2). Results also downplayed the relevance of the trans-10 to trans-11 shift as an effective marker of diet-induced MFD in sheep, and challenged the involvement of some trans-10 intermediates (e.g., trans-10 18:1 and trans-10 cis-15 18:2) in the low-fat milk syndrome in this species. Conversely, increased abundance of most 18:3 intermediates (including some unidentified isomers) might be representative of ruminal alterations related to fish oil supplementation in ewes. Further research is necessary to examine the potential association between these findings and MFD in lactating animals., This work was supported by the Spanish Ministry of Economy and Competitiveness (MINECO; AGL2014- 54587-R and AGL2017-87812). P. G. Toral benefits from a Ramón y Cajal research contract from the MINECO (RYC-2015-17230). Co-funding by the European Regional Development Fund is also acknowledged. The authors thank V. Peiró, R. Sedano, and R. Redondo (Autonomous University of Madrid, Spain) for their assistance in gas chromatography-combustion isotope ratio mass spectrometry analysis.

13 páginas, 1 figura, 6 tablas., Both sheep and goats can display very different individual degrees of milk fat depression (MFD), which might explain some apparent contradictions in the literature. Because the antilipogenic effect of certain fatty acids (FA) is the most likely origin of MFD, characterizing the milk FA profile of animals showing different degrees of MFD seems a helpful step to understand the physiological basis of the tolerance or susceptibility to the syndrome. Analyzing whether specific traits may predetermine a particular responsiveness would also be of relevance to meet this aim. However, information about these aspects is scant, not only in goats and sheep but in ruminants in general. This study was conducted with 25 Murciano-Granadina does and 23 Assaf ewes that were fed a total mixed ration without lipid supplementation for 3 wk (control period). Then, all animals received the same basal diet supplemented with 2% of fish oil (FO) for 5 additional weeks (MFD period). At the end of this second period, and on the basis of the extent of FO-induced decreases in milk fat concentration, the 5 most responsive (RESPON+) and the 5 least responsive (RESPON−) animals were selected within each species, 20 in total. Milk yield and composition, including a comprehensive FA profile, were examined at the end of each period. By design, between-group variation in milk fat concentration and yield was substantial, but no significant interaction with the effect of species was detected. Reductions in these 2 performance traits averaged 6% in RESPON− and 26% in RESPON+. Results do not allow suggesting that responsiveness to MFD would be clearly predetermined neither by the studied performance traits nor by milk FA profile, although a certain relationship with energy balance might exist. Furthermore, variations in ewes and does displaying different individual degrees of MFD may be associated with changes in certain candidate milk fat inhibitors, such as trans-10 18:1 and cis-9 16:1, whereas trans-10,cis-12 conjugated linoleic acid would only have a minor role in determining MFD severity. Alterations in the molar yield of de novo and preformed FA suggest relevant differences in the mechanisms underlying MFD in RESPON+ and RESPON−, with interspecies effects being observed only in more tolerant animals. Further research is still required to elucidate key determinants of responsiveness to MFD., This work was supported by the Spanish Research State Agency (Agencia Estatal de Investigación) and the European Regional Development Fund (project AGL2017-87812-R, AEI/FEDER, EU). A. Della Badia benefited from an FPI predoctoral contract (PRE2018-086174) and P. G. Toral from a Ramón y Cajal research contract (RYC-2015-17230), from the Spanish Ministries Science and Innovation (MICINN) and of Economy and Competitiveness (MINECO), respectively. Co-funding by the European Social Fund is also acknowledged. The authors have not stated any conflicts of interest.

11 páginas, 4 tablas, 1 figura., Milk odd- and branched-chain fatty acids (OBCFA) are largely derived from bacteria leaving the rumen, which has encouraged research on their use as biomarkers of rumen function. Targeted research has examined relationships between these fatty acids (FA) and dietary components, but interactions between the effects of lipids and other nutrients on milk OBCFA are not well characterized yet. Furthermore, factors controlling milk OBCFA in sheep are largely unknown. Thus, the present meta-analysis examined relationships between diet composition and milk OBCFA using a database compiled with lot observations from 14 trials in dairy ewes fed lipid supplements. A total of 47 lots received lipid supplements, whereas their respective controls (27 lots) were fed the same basal diets without lipid supplementation. Relationships between milk OBCFA and dietary components were first assessed through a principal component analysis (PCA) and a correlation analysis. Then, responses of milk OBCFA to variations in specific dietary components (selected on the basis of the PCA) were examined in more detail by regression analysis. According to the loading plot, dietary unsaturated C18 FA loaded opposite to major milk OBCFA (e.g., 15:0, 15:0 anteiso, and 17:0) and were strongly correlated with principal component 1, which described 46% of variability. Overall, regression equations supported this negative, and generally linear, relationship between unsaturated C18 FA levels and milk OBCFA. However, the influence of C20–22 n-3 polyunsaturated FA and saturated FA was more limited. The PCA also suggested that dietary crude protein is not a determinant of milk OBCFA profile in dairy ewes, but significant relationships were observed between some OBCFA and dietary fiber or starch, consistent with a potential role of these FA as biomarkers of rumen cellulolytic and amylolytic bacteria. In this regard, regression equations indicated that iso FA would show opposite responses to increasing levels of acid detergent fiber (positive linear coefficients) and starch (negative linear coefficients). Lipid supplementation would not largely affect these associations, supporting the potential of OBCFA as noninvasive markers of rumen function under different feeding conditions (i.e., with or without lipid supplementation). Because consumption of these FA may have nutritional benefits for humans, the use of high-fiber/low-starch rations might be recommended to maintain the highest possible content of milk OBCFA in dairy sheep., This work was supported by the Spanish Research State Agency (Agencia Estatal de Investigación) and the European Regional Development Fund (project AGL2017-87812-R, AEI/FEDER, UE). P. G. Toral benefited from a Ramón y Cajal research contract (RYC-2015-17230) and A. Della Badia from a FPI predoctoral contract (PRE2018-086174), from the Spanish Ministries of Economy and Competitiveness (MINECO) and Science and Innovation (MICINN), respectively. Co-funding by the European Social Fund is also acknowledged. The authors thank M.-P. Létour-neau-Montminy (Université Laval, Québec, Canada) for helpful assistance with statistical analysis. The authors have not stated any conflicts of interest.

14 páginas, 5 tablas, 2 figuras., The causative relationship between ruminal biohydrogenation alterations known as the trans-10 shift and marine lipid-induced milk fat depression (MFD) has been questioned in dairy ewes, but the large intra- and inter-experiment differences in the levels of trans-10 shift indicators precludes firm conclusions. This meta-analysis was conducted to quantify the relationship between trans-10 shift milk indicators [i.e., trans-10,cis-12 conjugated linoleic acid (CLA), trans-10 18:1 or trans-10:trans-11 18:1 ratio] and lactation performance, mainly milk fat traits, in Assaf dairy ewes. A database comprising of 17 experiments including 50 dietary treatments was compiled. The diets were grouped into 2 dietary conditions: (1) non-MFD condition, which included 14 diets supplemented with plant oils and tannins that modified the milk fatty acid profile without lowering milk fat concentration and yield, and 12 respective control diets, and (2) MFD condition, which included 15 diets supplemented with marine lipids that induced the low fat-milk syndrome, and 9 respective control diets. The overall levels of milk trans-10 shift indicators did not differ between dietary conditions, but significant increments were found in the supplemented diets relative to their respective controls. A similar linear and negative (slope: −7.28 ± 2.816) relationship between milk fat concentration and trans-10,cis-12 CLA was found in both dietary conditions. However, the quadratic negative response of milk fat content to trans-10 18:1 concentration was greater in MFD than in non-MFD conditions. In the two dietary conditions, the relationship between milk trans-10,cis-12 CLA or trans-10 18:1 and de novo fatty acid concentration in milk was negative, whereas the relationship with preformed fatty acid proportion was positive. The magnitude of changes in both milk fatty acid groups in response to changes in these trans-10 shift indicators were greater in non-MFD compared with MFD conditions. Milk fat yield and trans-10 shift indicators were only negatively related in ewes that were fed marine lipid supplements, because reductions in de novo fatty acid yield with increased shift indicator levels were not counteracted by concomitant increments in preformed fatty acid secretion. The best-fit (lower root mean squared error, higher R2 and no prediction biases) equations of milk fat or major milk fatty acid groups, as concentration or yield, were based on milk trans-10 18:1 concentration. In conclusion, different responses between the two conditions to similar shift indicator levels support that the trans-10 shift would not be a major factor explaining the diet-induced low-fat milk syndrome in dairy ewes., This work was supported by the Spanish Ministry of Economy and Competitiveness (MINECO; AGL2017-87812-R), co-funded by the European Regional Development Fund. P. G. Toral benefited from a Ramón y Cajal research contract from the MINECO (RYC-2015-17230), co-funded by the European Social Fund, and a researcher mobility grant from the University of León.

La alta prevalencia de suicidio en población adolescente en todo el mundo supone un reto mundial en salud mental. El ambiente familiar ha sido señalado como una importante variable implicada en el riesgo de suicidio de los adolescentes, ejerciendo tanto de factor de riesgo como protector. El estudio tiene como objetivo entender qué variables del funcionamiento familiar de la Escala de Clima Social en la Familia se relacionan con la puntuación de la Escala de Ideación Suicida de Beck en una muestra 37 adolescentes entre 14 y 18 años (M = 15.76; DT = 1.07) con rasgos de personalidad límite. Se partió de la hipótesis de que peores niveles de funcionamiento familiar aumentarían el riesgo de suicidio. Los resultados mostraron que la ideación suicida era mayor cuando las puntuaciones en la escala Relaciones (calidad de la comunicación e interacción) en la familia eran menores. Al analizar cada escala, se demostró la importancia específica de la subescala Expresividad, referida al grado de expresión libre de los sentimientos en la familia de forma que, a menor expresividad en la familia, mayor ideación suicida presentaban los adolescentes, y la subescala Social-Recreativa, referida a la participación social y en actividades de ocio de la familia, de modo que a mayor participación social, menor riesgo suicida. Estos resultados son apoyados por otros estudios que demuestran la importancia de modificar el entorno familiar para influir en el riesgo suicida de los adolescentes. El valor de estos datos implica la consideración de incluir a las familias en los programas de tratamiento para adolescentes suicidas. Family functioning in suicidal adolescents with borderline personality traits. High prevalence of suicide in adolescent population all over the world is considered a world challenge in mental health. Family environment has been pointed as an important factor involved in adolescents’ suicide risk, playing a role not only as a risk factor but also as protective. This study has its goal on understanding which factors of the family functioning, measured by the Social Environment in the Family Scale, are related to the total score of the Beck Suicide Ideation Scale in a sample of 37 adolescents with ages between 14 and 17 years old (M = 15.76; SD = 1.06) borderline personality traits. It was hypothesized that worse levels of family functioning will increase suicide risk in adolescents. Results showed that the risk of suicide was higher when the Relationships Scale total score (quality of communication and interaction in the family) was lower. After analyzing each subscale separately, it was demonstrated the specific relevance of Expressivity Subscale, referred to the level of free expression of feelings in the family, suggesting that the lower expressivity in the family, the higher suicide ideation showed by the adolescents, and Social-Recreative, referred to the social participation and leisure of the family, what means the more social participation, the less suicide ideation. These results are supported by other studies that show the relevance of modifying the family environment for reducing the suicidal risk among adolescents. The value of this data involves taking into account the families in the treatment programs for suicidal adolescents.

12 páginas, 5 tablas., Dairy ewes are less prone than cows to milk fat depression (MFD) but suffer from this syndrome when marine lipids are added to their diet to modulate milk fatty acid (FA) profile. However, there are large individual differences in MFD extent, and the reasons behind this variability are uncertain. On this basis, a study was conducted in lactating sheep to test the hypotheses that individual susceptibility to the low-fat milk condition may be explained by differences in (1) the milk concentration of some FA, particularly antilipogenic FA, or (2) the transcriptional regulation of mammary lipogenesis. For 5 wk, 15 ewes received a total mixed ration supplemented with 0 (control; n = 5) or 20 g of fish oil/kg of dry matter [10 animals selected out of 22 and divided into those showing marked (RESPON+; n = 5) or mild (RESPON-; n = 5) MFD]. Milk production and composition, including a comprehensive FA profile, were examined on 3 consecutive days before and after treatments. Candidate gene expression was also analyzed before the start of the trial and at its end using RNA isolated from milk somatic cells. According to the experimental design, the fish-oil-induced decrease in milk fat concentration was much stronger in RESPON+ (-25.4%) than in RESPON- (-7.7%). Milk from all ewes fed the supplemented diet showed rather uniform changes in the proportion of potentially healthy FA (such as cis-9,trans-11 18:2, trans-11 18:1, or 20:5n-3) and of those with confirmed or putative antilipogenic effects (e.g., cis-9 16:1, trans-10 and cis-11 18:1, trans-9,cis-11 18:2, and 10-oxo-18:0), without significant variation between RESPON+ and RESPON-. It was not possible to relate the very few exceptions to this general trend (e.g., in cis-7 16:1 and 22:6n-3) to responsiveness. Major mechanisms involved in mammary lipogenesis, specifically the uptake and de novo synthesis of FA, appeared to be unequally inhibited in ewes displaying different degrees of MFD, with molar yields of >16C FA being unaffected in RESPON-. However, this was not reflected in candidate gene expression. Supplementation with fish oil showed a tendency to lower the mRNA abundance of lipogenic genes such as ACSS2, FASN, LPIN1, FADS2, and INSIG1, but only SCD and GPAT4 tended to differ between RESPON- and RESPON+. Overall, these results offer no convincing support for the initial hypotheses, so further research must be pursued to explain the individual variation in MFD severity. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved., This study was supported by the Spanish Ministry of Economy and Competitiveness (MINECO; AGL2014- 54587-R). The authors thank L. Rodríguez (FPI predoctoral grant, MINECO) and A. G. Mendoza for their help with experimental animals and fatty acid analysis. P. G. Toral benefits from a Ramón y Cajal research contract from the MINECO. Co-funding by the European Regional Development Fund is also acknowledged.

11 páginas, 4 tablas, 2 figuras., Milk fat depression (MFD) caused by trans-10 cis-12 18:2 is known to be mediated in cows and ewes by downregulation of mammary lipogenic genes. However, transcriptional mechanisms underlying marine lipid-induced MFD have not been well defined yet and the few available studies in ovine are not consistent. This trial was conducted to directly compare changes in animal performance, milk fatty acid (FA) composition and particularly mammary mRNA abundance of candidate lipogenic genes and transcription factors (14 genes in total) in response to the inclusion of fish oil or trans-10 cis-12 18:2 in dairy sheep diet. To meet this objective, 12 lactating Assaf ewes (days in milk (DIM) = 64 ± 1.9; milk yield = 1.72 ± 0.135 kg/d; milk fat concentration = 5.17 ± 0.228%) were divided into 3 groups and offered a total mixed ration without supplementation (control) or supplemented with 2.4% DM of fish oil (FO) or 1% DM of a commercial product rich in trans-10 cis-12 18:2 (Lutrell Pure; CLA) for 39 days. Measurements and samplings were conducted before starting the treatments and at the end of the trial. Milk samples were used for RNA extraction from somatic cells. Feed intake was not affected by lipid supplements and, as designed, reductions in milk fat concentration (‒31%) were similar in the two treatments, although the unpredicted increase in milk production with FO counteracted the anticipated reduction in milk fat yield. Nevertheless, this did not preclude the detection of FO-induced decreases in the mRNA abundance of candidate lipogenic genes (e.g., ACSS2, FASN and LPIN1), thus supporting the hypothesis that transcriptional regulation would be a relevant component of this type of MFD in sheep. Expected CLA-induced downregulation of some genes, such as FASN or SREBF1, could not be detected in our samples, which might be related, at least in part, to high inter-individual variation and relatively advanced lactation stage (on average 102-103 DIM on days 38 and 39). Overall, direct comparison of the effects of dietary FO and CLA on transcript abundance of candidate lipogenic genes and transcription factors suggest that there might be relevant differences in the transcriptional control mechanisms underlying the MFD induced by each kind of supplement (i.e., fish oil or CLA)., This work was supported by the Spanish Ministry of Economy and Competitiveness (MINECO; AGL2014-54587, co-funded by the European Regional Development Fund). P. G. Toral gratefully acknowledges receipt of a postdoctoral research contract from the MINECO (Juan de la Cierva program). The authors thank Y. Chilliard, L. Bernard, C. Leroux (INRA, Clermont-Ferrand, France), and J. J. Arranz and A. Suárez-Vega (University of León, Spain), for helpful assistance with nutrigenomic techniques.

9 páginas, 2 figuras, 1 tabla., The role of marine lipids as modulators of ruminal biohydrogenation of dietary unsaturated fatty acids may be explained by the effects of their n-3 polyunsaturated fatty acids (PUFA) on the bacterial community. However, the impact of individual PUFA has barely been examined, and it is uncertain which bacteria are truly involved in biohydrogenation. In addition, despite interspecies differences in rumen bacterial composition, we are not aware of any direct comparison of bovine and ovine responses to dietary PUFA. Therefore, rumen fluid from cannulated cattle and sheep were used as inocula to examine in vitro the effect of 20:5n-3 (EPA), 22:5n-3 (DPA), and 22:6n-3 (DHA) on the bacterial community. Amplicon 16 S rRNA sequencing suggested that EPA and DHA had a greater contribution to the action of marine lipids than DPA both in cattle and sheep. Certain effects were exclusive to each ruminant species, which underlines the complexity of rumen microbial responses to dietary fatty acids. Based on changes in bacterial abundance, Barnesiella, Prevotella, Paraprevotella, Hallela, Anaerovorax, Succiniclasticum, Ruminococcus and Ruminobacter may be involved in the ruminal response in biohydrogenation to the addition of marine lipids, but further research is necessary to confirm their actual role in ruminal lipid metabolism., 54587-R and AGL2017-87812-R). D. Carreño benefited from an FPI predoctoral grant (BES-2012-054972) and P. G. Toral from a Ramón y Cajal research contract (RYC-2015-17230), both from the MINECO. Co-funding by the European Regional Development Fund and the European Social Fund is also acknowledged.

Identifying differences in the clinical response to specific interventions is an important challenge in the field of Clinical Psychology. This is especially true in the treatment of depression where many treatments appear to have comparable outcomes. In a controlled trial, we compared a positive psychology group intervention, the Integrative Positive Psychological Intervention for Depression (IPPI-D; n = 62) to a cognitive-behavioral therapy group intervention (CBT; n = 66) for depression. No statistically or clinically-significant differences between the treatments were found, but a slight advantage was observed, on average, for IPPI-D. The aim of the present study was to identify and combine moderators of the differential efficacy of these two psychological interventions for clinical depression. For this purpose, a secondary analysis using the Personalized Advantage Index (PAI) was performed to identify the intervention predicted to produce the better outcome for each patient. Six of the 21 potential moderators were found to predict differential efficacy between the treatments. IPPI-D was predicted to be the optimal treatment for 73% of the sample. Baseline features that characterized these individuals were: mental and physical comorbidity, prior antidepressant medication, higher levels of negative thoughts, and higher personal growth. The 27% who were predicted to achieve better outcomes in CBT than in IPPI-D tended to have these baseline features: no comorbidities, no prior antidepressant medication, lower levels of negative thoughts, and lower personal growth. pre-print 398 KB

Despite the variety of empirically supported treatments for depression, many available evidence-based treatments do not satisfactorily promote or maintain clinically significant changes in patients. Moreover, treatments for depression have been primarily focused on reducing patients' symptoms or deficits and less concerned with building positive resources that seem to be of interest to depressed individuals. This paper describes a manualized protocol of a new empirically-validated positive psychological intervention for depression, which incorporates a balance between hedonic and eudaimonic components and a combination of in-session exercises and homework. The protocol is a 10-session program, in a group format, and includes interventions that have been shown to be effective in increasing well-being or alleviating depressive symptoms. The rationale for developing this protocol, the underlying theoretical framework and some general guidelines for its application are presented. Furthermore, the implications of this protocol are discussed, demonstrating how it overcomes some of the limitations of current, evidence-based psychological treatments for depression. pre-print 1087 KB

14 páginas, 6 tablas., This study was funded by the Instituto de Ganadería de Montaña (CSIC-University of León, Spain) and the University of Perugia (Department DSA3; project “Ricerca di Base – 2015”). P. G. Toral benefits from a ‘Ramón y Cajal’ research contract (MINECO-European Regional Development Fund).

Shifts in ruminal oleic acid (OA) metabolism have received little research attention but recent studies have suggested their association with marine lipid-induced milk fat depression (MFD) in ewes and cows. Measurement of specific products of OA within the complex mixture of digesta lipids is however challenging. Therefore, this in vitro trial combined the isotopic labelling technique with the use of rumen inoculum from cannulated sheep fed a diet supplemented or not with 2% of fish oil (which has been demonstrated to cause MFD in dairy ruminants) to characterize the metabolism of OA in response to ruminal alterations associated with MFD. The products of 13C-OA after 24 h of incubation were analysed by gas chromatography-combustion isotope ratio mass spectrometry (GC-C-IRMS). Numerous 13C-labeled 18:1 intermediates and oxygenated FA were detected and no elongation or desaturation of 13OA occurred. Diet supplementation with fish oil (i.e., MFD conditions) resulted in no unique metabolites of 13OA but in relevant changes in the relative contribution of specific metabolic pathways. The inhibition of 18:0 saturation caused by this treatment appeared largely attributable to increased oxygenated FA proportion, in particular the candidate milk fat inhibitor 10-oxo-18:0, and warrants further research on the association between MFD and oxygenated FA. Changes in the concentration of 13C-labeled trans 18:1 intermediates but not in cis 18:1, were also observed., This research was funded by the Spanish Ministry of Economy and Competitiveness (MINECO; AGL2017-87812). P. G. Toral benefits from a Ramón y Cajal research contract from the MINECO (RYC-2015-17230). Co-funding by the European Regional Development Fund is also acknowledged.

16 páginas, 5 figuras., Tannins are a large, diverse and complex group of phenolic compounds that may be detrimental, innocuous or beneficial to animal nutrition and health depending on a number of factors (e.g., type, amount ingested, consumer animal species or the basal diet). The ability of tannins to modulate ruminal biohydrogenation and, consequently, the fatty acid (FA) composition of milk and meat is a relatively recent finding that has attracted interest among ruminant nutritionists. In this review, we take a close look at the effects of tannins on the broadest possible range of FA, including less abundant compounds that have previously received little attention. Tannins are able to improve the concentrations of potentially beneficial FA, such as 18:3n-3, 18:2n-6, trans-11 18:1 and conjugated linoleic and linolenic acids, both in milk and meat, which may contribute to meeting consumer demand for health-promoting foods. These positive responses to tannins can be explained by their modulatory action on specific biohydrogenation steps and pathways. Thus, higher contents of dietary polyunsaturated FA in ruminant-derived products, as well as increased or decreased accumulation of other biohydrogenation intermediates (e.g., cis and trans 18:3, 18:2 and 18:1 isomers) and changes in lipids of bacterial origin (odd- and branched-chain FA and dimethylacetals), are somewhat common findings when the effects of tannins are examined. In contrast, de novo synthesized FA are less frequently affected by these plant secondary metabolites, which also applies to other FA (e.g., trans-10 18:1) that might be detrimental to animal performance (i.e., milk fat synthesis) and perhaps to human health. However, further studies are required to unravel the reasons for certain erratic responses to tannins. This paper reviews the roles of tannin chemical and structural diversity, dosage, interaction with other dietary ingredients, differences among ruminant species and variations over time in the reaction of rumen microbiota in the influences of these phenolic compounds on milk and meat FA profiles., P. G. Toral benefited from a Ramón y Cajal research contract from the MINECO (RYC-2015-17230), co-funded by the European Social Fund.

Traditionally, treatments for depression have been primarily focused on reducing patients’ symptoms or deficits and less concerned with building positive resources. This study aims to compare the efficacy of a manualized protocol of empirically-validated positive psychology interventions (PPI) with a cognitive-behavioral therapy (CBT) protocol. This controlled clinical trial included 96 adult women with a DSM-IV diagnosis of major depression or dysthymia. Participants were blindly allocated to a 10-session PPI (n = 47) or CBT (n = 49) group therapy condition. Intention to treat analysis showed that both interventions were effective in reducing clinical symptoms and increasing well-being. There were no significant differences between groups in either main outcomes (i.e., severity of depressive symptoms and clinical diagnosis) or secondary outcomes (e.g., positive and negative affect, and satisfaction with life). Even within the most severely depressed participants, no differences between PPI and CBT emerged. If further clinical studies confirm these results, this would widen treatment choice for both patients and professionals.

This work investigated the effects of feeding silage mixtures of a plant containing polyphenol oxidase (PPO; red clover [; RC]), a plant containing tannins (sainfoin [; SF]), and a grass species not containing these compounds (timothy [; T]) on ruminal and intramuscular (i.m.) fatty acids of lambs. Forty 4-mo-old castrated male Romane lambs, divided into 5 groups, received 1 of the following silages: 1) T (100%), 2) a binary mixture of timothy and tannin-containing sainfoin ( cv. Perly; 50:50 [T-SF]), 3) a binary mixture of timothy and PPO-containing red clover ( cv. Mervius; 50:50 [T-RC]), 4) a ternary mixture of timothy, sainfoin, and red clover containing both tannins and PPO (50:25:25, respectively [T-SF-RC]), and 5) a binary mixture of tannin-containing sainfoin and PPO-containing red clover (50:50 [SF-RC]). In the rumen digesta, the partial or total replacement of T with forage legumes was associated with greater concentrations of PUFA ( < 0.001) and 1esser concentrations of MUFA ( < 0.001). The inclusion of forage legumes in the silage favored the accumulation of 18:3 -3 ( < 0.001), with the greatest concentrations being observed in SF-RC. This latter diet also led to the greatest percentage of 18:2 -6 ( < 0.001). Forage legumes decreased the -11 18:1 to 30% of T in rumen digesta ( < 0.001). Forage legumes decreased the total concentration of branched-chain fatty acids in the rumen digesta (on average, -28%; < 0.001), this effect being less marked (-17%; = 0.014) in T-RC in comparison with T. The dietary treatment tended to affect the proportion of MUFA ( = 0.081) and of PUFA ( = 0.079) in the i.m. fat of the LM, respectively, at the highest and lowest numerical value in the T group. The sum of -3 fatty acids was less in the T and T-SF groups compared with the mixture of legumes without T (SF-RC; < 0.001 and < 0.008, respectively). The latter group had also a lesser -6-to--3 ratio than the T-SF group ( = 0.01). -11 18:1 was greater ( < 0.03) in lambs given T as the sole silage in comparison with lambs given T-RC, T-SF-RC, and SF-RC. Rumenic acid (-9 -11 CLA) was detected at a greater percentage in the LM from the animals fed the T silage compared with animals fed the T-SF-RC treatment ( = 0.004). Contrarily, -9 -12 -15 18:3 was found at a greater concentration in the muscle from lambs in the SF-RC treatment compared with lambs in the other treatments ( < 0.001). Furthermore, the T-RC group showed a greater proportion of α-linolenic acid than the T group ( = 0.03). In conclusion, the effects of the 2 active compounds (PPO and tannins) appear to be similar and additive. Moreover, a silage composed of a mixture of RC and SF is an excellent forage for growing lambs in terms of i.m. fatty acid composition.

12 páginas, 6 tablas., Supplementation of dairy ewe diet with marine lipids may be an effective strategy for modulating milk fatty acid composition but induces milk fat depression (MFD). This syndrome has been associated with a shortage of 18:0 for uptake and Δ9-desaturation that may impair the capacity of the mammary gland to achieve an adequate fluidity for milk fat secretion. On this basis, it was suggested that supplemental 18:0 may contribute to alleviate marine lipid-induced MFD in sheep. To test this hypothesis, 12 lactating ewes were allocated to 1 of 3 lots and used in a 3 × 3 Latin square design with 3 periods of 28 d each and 3 experimental treatments: a total mixed ration without lipid supplementation (control) or supplemented with 20 g/kg of DM of fish oil alone (FO) or in combination with 20 g/kg of DM of 18:0 (FOSA). Diets were offered ad libitum, and animal performance and rumen and milk fatty acid composition were studied at the end of each period. After completing the Latin square trial and following a change-over design, the in vivo digestibility of supplemental 18:0 was estimated using 6 lactating sheep. As expected, diet supplementation with fish oil increased the milk content of some potentially health-promoting fatty acids (e.g., cis-9,trans-11 18:2, trans-11 18:1, 20:5n-3, 22:5n-3, and 22:6n-3), but reduced milk fat concentration and yield (−20% in both FO and FOSA treatments). Thus, although reductions in milk 18:0 and cis-9 18:1 output caused by FO (−81 and −51%, respectively) were partially reversed with FOSA diet (−49 and −27%, respectively), the addition of 18:0 to the diet did not prove useful to alleviate MFD. This response, which could not be fully accounted for by the low digestibility coefficient of supplemental 18:0, may challenge the theory of a shortage of this fatty acid as a mechanism to explain fish oil-induced MFD in sheep. Effects of FO and FOSA on rumen and milk fatty acid composition would support that increases in the concentration of some candidate milk fat inhibitors (e.g., cis-9 16:1 or 10-oxo-18:0) might play a relevant role in this type of MFD., This work was supported by the Council of Castile and Leon (CSI023U13) and the Spanish Ministry of Economy and Competitiveness (MINECO; AGL2011- 23700). P. G. Toral and D. Carreño benefit from a Juan de la Cierva research contract and an FPI predoctoral grant, respectively, from the MINECO.

8 páginas, 3 tablas, 1 figura., The direct comparison between milk fat depression (MFD) caused by the addition of trans-10 cis-12 18:2 (a conjugated linoleic acid –CLA– isomer) or marine lipids to the diet of dairy ewes may help to elucidate the origin of this syndrome. Therefore, 12 lactating sheep were divided in 3 lots and offered a diet without supplementation (control) or supplemented with 2% DM of fish oil (FO) or 1.1% DM of a rumen-protected product rich in trans-10 cis-12 18:2 (CLA) for 27 days to compare the responses in terms of animal performance and milk fatty acid (FA) profile. Both supplemented diets (FO and CLA) decreased the milk fat content in a similar manner (–18% compared with the control). On the other hand, responses in milk FA profiles differed significantly and support that marine lipid-induced MFD is not mediated by the effects of trans-10 cis-12 18:2. However, a comparison of changes in the molar production of milk FA show that de novo FA synthesis was affected similarly in FO and CLA treatments and more strongly than FA uptake, which implies that both types of MFD might share common mechanisms. The results point to the involvement of less well-known potentially antilipogenic metabolites (such as intermediates of 18:3n-3 biohydrogenation or ruminal hydration and oxidation) in the low-milk fat syndrome in ewes fed FO and seem to downplay the relevance of changes in the milk fat melting point as a major mechanism responsible for FO-induced MFD., This work was supported by the Spanish Ministry of Economy and Competitiveness (MINECO; AGL2014-54587). P.G. Toral and D. Carreno˜ benefit from a Juan de la Cierva research contract and an FPI predoctoral grant, respectively, from the MINECO.

The lactational effects of shearing (CO, control unshorn; SH, shorn) were investigated in 48 dairy ewes of 2 breeds (Lacaune, LC, n = 24; Manchega, MN, n = 24) having a similar stage of lactation (120 ± 6 d in milk) and body frame (65.1 ± 1.5 kg of body weight and 2.4 ± 0.1 body condition score), but differing in fleece and milk production. Ewes were penned indoors, adapted to the diet (alfalfa hay ad libitum and fixed amount of concentrate), and allocated for 30 d in 8 balanced groups to which the experimental treatments were applied. All ewes were sheared on the same day. Feed intake by pen and milk yield by ewe were recorded daily. Individual samples of milk (d -3, 3, 5, 7, and 15) and blood (d -7, 3, 7, and 15) were collected, as well as body weight and body condition score measured (d -15, 0, and 15), related to shearing. Pooled milk samples per pen were also collected before and after shearing for milk fatty acid analysis (d -3 and 15). Average temperatures in the barn before (12.6 ± 0.7°C) and after (13.7 ± 0.4°C) shearing were mild. Fleece was heavier in MN than in LC (1.04 ± 0.10 vs. 0.75 ± 0.09 kg/ewe) and tended to cover more body surface in MN than in LC ewes. Responses to shearing varied according to breed, the rectal temperature after shearing only decreasing significantly in the MN (-0.36 ± 0.09°C). Feed intake increased in the LC-SH (5%), when compared with LC-CO, but did not vary in the MN ewes. Ingestibility of the alfalfa hay, expressed as filling units for sheep and monitored in 2 groups of 6 dry and unshorn ewes of each breed (73.0 ± 2.5 kg of body weight and 3.1 ± 0.2 body condition score), was constant throughout the experiment (0.99 ± 0.03 filling units for sheep/kg of dry matter). Regarding milk production, LC-SH ewes yielded 10% more milk (1.38 ± 0.06 vs. 1.52 ± 0.05 kg/d) than LC-CO ewes, but no differences were detected in MN ewes (0.74 ± 0.03 kg/d, on average). No differences in the concentration of major milk components by effect of the shearing treatment were detected in either breed, but LC-SH ewes yielded 9% more milk protein than did LC-CO ewes. No relevant effects of shearing were detected on milk fatty acid profiles, although MN ewes showed lower C4:0, C6:0, C14:0, trans-11 and trans-12 C18:1 contents than did LC ewes. Moreover, no changes by effect of shearing were detected in plasma glucose, nonesterified fatty acids, cortisol, or insulin values in either breed, or in body weight or body condition score. In conclusion, shearing dairy ewes during lactation under mild winter conditions is a suitable management option that may increase feed intake and milk production, without deleterious effects on milk composition.

10 páginas, 2 tablas., Growth in demand for foods with potentially beneficial effects on consumer health has motivated increased interest in developing strategies for improving the nutritional quality of ruminant-derived products. Manipulation of the rumen environment offers the opportunity to modify the lipid composition of milk and meat by changing the availability of fatty acids (FA) for mammary and intramuscular lipid uptake. Dietary supplementation with marine lipids, plant secondary compounds and direct-fed microbials has shown promising results. In this review, we have compiled information about their effects on the concentration of putative desirable FA (e.g. c9t11-CLA and vaccenic, oleic, linoleic and linolenic acids) in ruminal digesta, milk and intramuscular fat. Marine lipids rich in very long-chain n-3 polyunsaturated fatty acids (PUFA) efficiently inhibit the last step of C18 FA biohydrogenation (BH) in the bovine, ovine and caprine, increasing the outflow of t11-18:1 from the rumen and improving the concentration of c9t11-CLA in the final products, but increments in t10-18:1 are also often found due to shifts toward alternative BH pathways. Direct-fed microbials appear to favourably modify rumen lipid metabolism but information is still very limited, whereas a wide variety of plant secondary compounds, including tannins, polyphenol oxidase, essential oils, oxygenated FA and saponins, has been examined with varying success. For example, the effectiveness of tannins and essential oils is as yet controversial, with some studies showing no effects and others a positive impact on inhibiting the first step of BH of PUFA or, less commonly, the final step. Further investigation is required to unravel the causes of inconsistent results, which may be due to the diversity in active components, ruminant species, dosage, basal diet composition and time on treatments. Likewise, research must continue to address ways to mitigate negative side-effects of some supplements on animal performance (particularly, milk fat depression) and product quality (e.g. altered oxidative stability and shelf-life)., This work was conducted within the framework of the research projects AGL2014-54587 and AGL2017-87812 (Spanish Ministry of Economy and Competitiveness, MINECO). P.G.T. benefited from a Ramón y Cajal research contract (RYC-2015-17230, MINECO).

8 páginas, 3 tablas., Despite the benefits of adding marine lipids rich in n-3 polyunsaturated fatty acids (PUFA) to ruminant diets to improve milk fatty acid (FA) composition, this strategy induces milk fat depression (MFD), precluding its application under practical conditions. The MFD elicited by marine lipids has tentatively been explained by a shortage of available ruminal 18:0 for mammary uptake and Δ9-desaturation to cis-9 18:1, which might increase milk fat melting point and impair fat secretion. This hypothesis was challenged in a recent experiment in dairy ewes, as diet supplementation with 2% DM of 18:0 did not prove useful to alleviate fish oil-induced MFD. However, further research with higher levels of 18:0 inclusion seemed advisable. Therefore, in this study, 16 lactating ewes were allocated to 4 treatments lasting 27 days: a total mixed ration containing no additional lipid (control) or 2% DM of fish oil alone (FO) or in combination with 3% (FOSA3) or 4% (FOSA4) of stearic acid. Fish oil supplementation induced MFD, but addition of 18:0, regardless of the dose, was not able to mitigate it: decreases in milk fat content reached 19% in FO, 20% in FOSA3 and 27% in FOSA4. The reduction in milk 18:0 concentration due to FO (−81%) was completely reverted neither by FOSA3 (−41%) nor by FOSA4 (−25%), and something similar occurred with cis-9 18:1 concentrations (12.53, 5.91, 9.50 and 11.28 g/100 FA, in control, FO, FOSA3 and FOSA4, respectively). Increases in some candidate milk fat inhibitors in FO and FOSA diets (e.g., cis-9 16:1, cis-11 18:1, trans-10 18:1, 10-oxo-18:0, or trans-10 cis-15 18:2) might account for the absence of a positive effect of dietary 18:0. The estimated milk fat melting point was lower in the three supplemented diets (on average, −2.6 °C compared with the control). In conclusion, addition of high doses of stearic acid to the diet (at 3 and 4% DM) was not able to alleviate the MFD caused by the concomitant supplementation with fish oil. This lack of response would further challenge the hypothesis suggesting that fish oil-induced MFD is mainly explained by decreased ruminal production of 18:0 and subsequent problems of milk fat fluidity, but further research would be still needed., This work was supported by the Council of Castile and Leon (CSI023U13). The authors thank D. Carreño, A. G. Mendoza and L. Rodríguez for their help with experimental animals and fatty acid analysis. Pablo G. Toral benefits from a Ramón y Cajal research contract from the Spanish Ministry of Economy, Industry and Competitiveness (RYC-2015-17230), co-funded by the European Regional Development Fund.