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Hybridization can result in the transfer of adaptive genetic material from one species to another, known as adaptive introgression. Bottlenecked (and hence genetically depleted) species are expected to be particularly receptive to adaptive introgression, since introgression can introduce new or previously lost adaptive genetic variation. The Alpine ibex (Capra ibex), which recently recovered from near extinction, is known to hybridize with the domestic goat (Capra aegagrus hircus), and signals of introgression previously found at the major histocompatibility complex were suggested to potentially be adaptive. Here, we combine two ancient whole genomes of Alpine ibex with 29 modern Alpine ibex genomes and 31 genomes representing six related Capra species to investigate the genome‐wide patterns of introgression and confirm the potential relevance of immune loci. We identified low rates of admixture in modern Alpine ibex through various F statistics and screening for putative introgressed tracts. Further results based on demographic modelling were consistent with introgression to have occurred during the last 300 years, coinciding with the known species bottleneck, and that in each generation, 1–2 out of 100 Alpine ibex had a domestic goat parent. The putatively introgressed haplotypes were enriched at immune‐related genes, where the adaptive value of alternative alleles may give individuals with otherwise depleted genetic diversity a selective advantage. While interbreeding with domestic species is a prevalent issue in species conservation, in this specific case, it resulted in putative adaptive introgression. Our findings highlight the complex interplay between hybridization, adaptive evolution, and the potential risks and benefits associated with anthropogenic influences on wild species. [ABSTRACT FROM AUTHOR]

This study's objective was to compare two options of pasture supplementation: corn silage (CS) alone or corn silage mixed with protein concentrate. The experiment was conducted with 18 lactating Holstein cows in mid‐lactation in a crossover design that included three treatments and three data collection periods. All cows had access to pasture for 17 h/day with an average herbage allowance of 16 kg dry matter (DM)/cow/day and were offered in‐barn corn silage, corn silage mixed with protein concentrate, or no supplementation. Cows were equipped with pH sensors residing in the reticulum and, during the 7‐day data collection periods, with a jaw movement recorder. Nonsupplemented cows produced 21.3 kg energy‐corrected milk (ECM) and ate 13.3 kg DM herbage at pasture. Cows supplemented with corn silage and corn silage plus protein produced 2.5 and 4.5 kg/day more ECM, respectively, consumed 3.4 and 3.3 kg/day more DM in total, respectively, ate for a shorter period of time, and ruminated longer than their nonsupplemented peers. Supplemented cows were almost able to cover their energy requirements and mobilised less body mass in contrast to the nonsupplemented cows. Cows offered corn silage plus protein showed increased ECM production, increased milk urea content and lower nitrogen use efficiency (NUE) compared to cows supplemented with corn silage only. Nonsupplemented dairy cows had the highest milk urea content and performed worst in terms of NUE. The best feed conversion efficiency resulted from the nonsupplemented dairy cows and those supplemented with corn silage plus protein. In nonsupplemented cows, the high feed conversion efficiency seemed to be due to the increased mobilisation of body mass. As a result of the starch‐rich supplementations, the ruminal acetic:propionic acid ratio became smaller, and the proportions of n‐butyric acid increased. The mean reticular pH values did not substantially vary across the three feeding treatments. For the choice of a supplementation option, herbage allowance and cost of supplement will have to be considered, but aspects of feed–food competition as well as animal welfare should not be ignored. [ABSTRACT FROM AUTHOR]

Calcar‐guided short stems in total hip arthroplasty (THA) permit surgeons to successfully reconstruct postoperative femoroacetabular offset, accurately restore leg length, and adequately re‐establish a wide range of caput‐collum‐diaphyseal angles. However, their effect on femoral antetorsion is less known. Indeed, controlling antetorsion of the femoral stem can be challenging because of the differences in individual femoral geometry and curvature. Therefore, we investigated if calcar‐guided short‐stem THA alters femoral antetorsion and compared it with conventional‐stem THA. Using 12 Thiel‐fixed, full‐body cadaver specimens from donors without known hip disorders, we compared an uncemented calcar‐guided femoral short‐stem prosthesis with an uncemented conventional straight‐stem prosthesis. In a paired study setup, each specimen received a calcar‐guided short stem on one side and a conventional stem on the other. On the acetabular side, all specimens received a press‐fit, monobloc acetabular cup. Femoral antetorsion angles were measured using the Waidelich method, and pre‐ and post‐operative angles of both sides were recorded. The mean preoperative femoral antetorsion angles were similar in both groups (24.8° ± 7.5° vs. 23.8° ± 6.1°, p = 0.313). Mean postoperative femoral antetorsion angles were 23.0° ± 5.5° in short‐stem and 13.5° ± 7.1° in conventional‐stem hips. Short‐stem hips had a small but nonsignificant difference in femoral antetorsion angles pre‐ and post‐operatively (1.8° ± 3.2°, p = 0.109), while the difference for conventional‐stem hips was much larger and highly significant (10.3° ± 5.8°, p < 0.001). Calcar‐guided short‐stem THA effectively restores femoral antetorsion. However, how this affects long‐term clinical outcomes and complications warrants further exploration. [ABSTRACT FROM AUTHOR]

Population bottlenecks can have dramatic consequences for the health and long‐term survival of a species. Understanding of historic population size and standing genetic variation prior to a contraction allows estimating the impact of a bottleneck on the species' genetic diversity. Although historic population sizes can be modelled based on extant genomics, uncertainty is high for the last 10–20 millenia. Hence, integrating ancient genomes provides a powerful complement to retrace the evolution of genetic diversity through population fluctuations. Here, we recover 15 high‐quality mitogenomes of the once nearly extinct Alpine ibex spanning 8601 BP to 1919 CE and combine these with 60 published modern whole genomes. Coalescent demography simulations based on modern whole genomes indicate population fluctuations coinciding with the last major glaciation period. Using our ancient and historic mitogenomes, we investigate the more recent demographic history of the species and show that mitochondrial haplotype diversity was reduced to a fifth of the prebottleneck diversity with several highly differentiated mitochondrial lineages having coexisted historically. The main collapse of mitochondrial diversity coincides with elevated human population growth during the last 1–2 kya. After recovery, one lineage was spread and nearly fixed across the Alps due to recolonization efforts. Our study highlights that a combined approach integrating genomic data of ancient, historic and extant populations unravels major long‐term population fluctuations from the emergence of a species through its near extinction up to the recent past. [ABSTRACT FROM AUTHOR]

Low plasma total cholesterol (TC) concentrations are characteristic during the negative energy balance in early lactating dairy cows. The objective was to investigate short‐term effects of different TC concentrations during an aggravated energy deficiency through a 1‐week concentrate withdrawal on adaptations of metabolism and milk production. Multiparous Holstein cows (n = 15) were investigated during 3 week beginning at 24 ± 7 DIM (mean ± SD). Cows were kept on pasture and received additional concentrate in experimental week 1 and 3, while in week 2, concentrate was withdrawn. Blood was sampled once and milk twice daily. Based on their average TC concentration during week 1 (prior to concentrate withdrawal), cows were retrospectively assigned into a high (H‐Chol; n = 8, TC ≥ 3.36 mmol/L) and a low TC groups (L‐Chol; n = 7, TC < 3.36 mmol/L). Concentrations of phospholipids and lipoproteins were higher in H‐Chol compared to L‐Chol throughout the study (p < 0.05). During concentrate withdrawal, milk yield, glucose and insulin concentrations decreased similarly in both groups, while milk fat, milk acetone and plasma BHB were higher in H‐Chol compared to L‐Chol (p < 0.05). Compared to initial values, plasma NEFA, TAG and VLDL increased in both groups within 2 days after concentrate withdrawal (p < 0.05). Concentrations of NEFA during week 2 were greater in L‐Chol compared to H‐Chol (p < 0.05). Despite reintroduction of concentrate, milk yield in H‐Chol remained lower for two more days compared to week 1 (p <.05), whereas milk yield recovered immediately in L‐Chol. Activity of aspartate aminotransferase was higher in H‐Chol compared to L‐Chol in week 2 (p < 0.05). Greater plasma TC concentrations were associated with a reduced increase of NEFA. Further research is warranted if TC concentrations are related to adipose tissue mobilization and fatty acid turnover. [ABSTRACT FROM AUTHOR]