| 1. |
- Cabezas Garcia, Edward Hernando
(författare)
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Effects of source and concentration of neutral detergent fiber from roughage in beef cattle diets: Comparison of methods to measure the effectiveness of fiber
- 2020
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Ingår i: Journal of Animal Science. - : Oxford University Press (OUP). - 0021-8812 .- 1525-3163. ; 98
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Tidskriftsartikel (refereegranskat)abstract
- Methods have been developed to measure the effectiveness of many roughages, but few evaluations have been conducted with tropical feeds. The objectives of this research were to determine the effectiveness of roughage sources based on bioassay and laboratory methods and identify the biological attributes of the diets that correlate with these methods. Six ruminally cannulated Nellore steers (408 +/- 12 kg of BW) were randomly assigned to a 6 x 6 Latin square design within six diets: negative control diet (NC) with aNDF as 10% from corn silage (CS); positive control diet (PC) with aNDF as 20% from CS; and four diets containing 10% aNDF from CS and 10% aNDF from each of the following sources: sugarcane (SC), sugarcane bagasse (SCB), soybean hulls (SH), or low oil cottonseed hulls (LOCH). Physical effectiveness factor (pef, related to the physical characteristics of aNDF) and effectiveness factor (ef, related to the ruminal pH) were determined based on a linear model approach that uses a bioassay method in which CS aNDF was assumed to be the standard fiber source. Laboratory methods to estimate pef of roughage sources were based on the proportion of DM of roughage retained on a 1.18-mm sieve pef(>1.18 mm) or retained on the 8.0-mm Penn State Particle Separator screen pef(>8.0 mm). The pef calculated by the bioassay method (total chewing time and ruminal mat resistance) for CS, SCB, and SC were higher values (P < 0.05) compared with SH and LOCH. The pef(rumen mat) of SC and SCB were higher (P < 0.05) than that of CS, SH, and LOCH. The pef(rumen mat) of LOCH was 61% higher than SH. The ef(rumen pH) of SC and LOCH was higher (P < 0.05) than CS and SH. The pef(chewing, min/d), pef(chewing, min/kg of DM), pef(rumen mat), and ef(rumen pH) positively correlated with rumination time, total chewing time, and ruminal mat resistance (values from transit time in seconds). No correlation was observed (P > 0.05) between pef(>8.0 mm) and rumination time, chewing time, and ruminal pH. The pef calculated using the bioassay method as well as pef (>8.0 mm) were negatively correlated with rumen pH (P > 0.05). The values of the effectiveness of fiber sources obtained in this research can be used as a guideline for nutritionists aiming to replace roughage sources from tropical regions in beef cattle finishing diets. Under our conditions, the pef using the bioassay method or laboratory methods were not adequate in predicting ruminal pH.
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| 2. |
- Cabezas Garcia, Edward Hernando
(författare)
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Effects of source and concentration of neutral detergent fiber from roughage in beef cattle diets on feed intake, ingestive behavior, and ruminal kinetics
- 2020
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Ingår i: Journal of animal science. - : Oxford University Press (OUP). - 0021-8812 .- 1525-3163. ; 98
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Tidskriftsartikel (refereegranskat)abstract
- The objectives of this research were to evaluate the effects of source and concentration of a-amylase-treated neutral detergent fiber (aNDF) from roughage on feed intake, ingestive behavior, and ruminal kinetics in beef cattle receiving high-concentrate diets. Six ruminally cannulated Nellore steers (408 +/- 12 kg of body weight) were randomly assigned to a 6 x 6 Latin square design with six diets: 10% aNDF from corn silage (10CS); 20% aNDF from corn silage (20CS); or four diets containing 10% aNDF from corn silage and 10% aNDF from one of the following sources: sugarcane (SC), sugarcane bagasse (SCB), soybean hulls (SH), or low oil cottonseed hulls (LOCH). The parameters of passage and degradation kinetics were estimated based on a two-compartmental model with gamma- and exponential-distributed residence times. The nonlinear models were fitted by nonlinear least squares, and a linear mixed-effects model was fitted to all variables measured from the Latin square design that were related to intake, digestibility, digestion kinetic parameters, and residence times. Mean particle size (MPS) between roughage sources (CS, SCB, and SC) and coproducts (SH and LOCH) was affected (P < 0.05). Dry matter intake (DMI) was not affected (P > 0.05) by 20CS, SC, SH, or LOCH. Steers fed 20CS or LOCH diets had 16% and 20% greater DMI, respectively, (P < 0.05) than steers fed 10CS diet. Steers fed SCB consumed the least dry matter (DM). The SH and LOCH diets had lower MPS values (about 8.77 mm) in comparison to 20CS, SCB, and SC diets (about 13.08 mm) and, consequently, affected (P < 0.05) rumen content, ruminal in situ disappearance, nutrient digestibility, and solid fractional passage rate. Chewing time was affected (P < 0.05) by roughage sources and concentration. Lower values of distance travel inside the rumen (min/cm) were observed (P < 0.05) for the SCB and SC diets in comparison with any other diet. Except for SCB, there was no difference (P > 0.05) in rumen fill, among other treatments. Mean daily ruminal pH was not affected (P > 0.05) by 20CS, SCB, SC, and LOCH diets, and it ranged from 6.1 to 6.23. Total short-chain fatty acids concentration was affected (P < 0.05) by roughage source and concentration. Based on our results, we recommend that under Brazilian finishing diets, replacing roughage sources, except for SCB, based on aNDF concentration of the roughage in high-concentrate diets containing finely ground flint corn does not affect DMI.
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| 3. |
- De Koning, Dirk-Jan
(författare)
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The Saga of Just One QTL; From Laying Hen Bone Strength to One Carbon Metabolism
- 2021
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Ingår i: Journal of Animal Science. - : Oxford University Press (OUP). - 1525-3163 .- 0021-8812. ; 99, s. 32-32
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Konferensbidrag (refereegranskat)abstract
- Skeletal damage is a challenge for laying hens, as the adaptations for egg laying make them susceptible to osteoporosis. We know that activity, growth and puberty influence skeletal quality genetics. However, in this story, we follow the process of resolving a QTL for skeletal quality to a single gene. Providing both a nutritional and a genetic solution and illustrating another level of complexity. Using divergently selected populations in an F2 cross, a QTL for skeletal quality was described. Utilising a series of experiments in the commercial founder line the QTL was fine mapped on chromosome 1 and the differences in physiology of hens that segregated for markers at the locus defined e.g. tibia breaking strength 200.4 vs 218.1 Newton (p< 0.002). Transcriptome profiling of tibia from the high and low bone strength genotype revealed a highly differentially expressed gene co localising to the QTL, the enzyme cystathionine beta synthase (CBS). CBS is a component of one carbon metabolism. Plasma homocysteine, the substrate of CBS had a higher concentration in the genotype associated with poor bone quality. Homocysteine interferes with crosslinking of the collagen matrix, critical to bone formation. Homocysteine can be re-methylated into methionine, a limiting amino acid in laying hens, using betaine as a methyl donor. Testing the hypothesis that reducing plasma homocysteine by feeding betaine, a widely available feed additive, would improve bone quality in laying hens proved successful.This is just one component of a complex trait and its elucidation took us along unexpected routes. However, I am optimistic that with modern tools and an open mind we can progress more quickly. Alongside understanding the factors that determine skeletal quality genetics, the discovery of the mechanisms behind complex traits, although rarely easy, offer the potential for novel interventions to improve animal health and production.
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| 4. |
- Gonzalez-Ramiro, Henar, et al.
(författare)
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Combined synchronization and superovulation treatments negatively impact embryo viability possibly by the downregulation of WNT/beta-catenin and Notch signaling genes in the porcine endometrium
- 2022
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Ingår i: Journal of Animal Science. - : Oxford University Press. - 0021-8812 .- 1525-3163. ; 100:11
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Tidskriftsartikel (refereegranskat)abstract
- The combination of estrus synchronization and superovulation treatments introduces molecular modifications whose effects are yet to be disclosed. Here, reproductive parameters and gene expression changes in ovaries and endometrium were explored on day 6 after artificial insemination (AI), when synthetic progestin altrenogest (ALT) was combined with gonadotropins. Sows were administered ALT for 7 d beginning on the day of weaning and superovulated with equine chorionic gonadotropin (eCG) 24 h later and human chorionic gonadotropins (hCG) at the onset of estrus (SS-7 group; n = 6). The controls were either superovulated sows with eCG 24 h postweaning and hCG at the onset of estrus (SC group; n = 6) or sows with postweaning spontaneous estrus (NC group; n = 6). Ovary examination and embryo and tissue collection were performed in all sows via laparotomy on day 6 post-AI. RNA-Seq was conducted to analyze differentially expressed genes (DEGs) between groups. Statistical analysis of the reproductive parameters was conducted with ANOVA and Tukey post hoc tests. DEGs were analyzed with an ANOVA (fold changes >= 2 or <= 2, P value <0.05). Hormonal treatments almost doubled (P < 0.03) the number of corpora lutea (39.8 +/- 10.2 and 38.3 +/- 11.1 in SS-7 and SC sows, respectively) compared with that in the NC group (23.1 +/- 3.8). In contrast, embryo viability significantly decreased (P < 0.003) in response to SS-7 treatment (75.1% +/- 15.2%) compared to SC and NC groups (93.8 +/- 7.6% and 91.8 +/- 6.9%, respectively). RNA-Seq analyses revealed 675 and 1,583 DEGs in the SS-7 group compared to both SC and NC groups in endometrial and ovarian samples, respectively. Interestingly, many genes with key roles in the Wnt/beta-catenin and Notch signaling pathways were differentially expressed in SS-7 sows relative to SC and NC groups (e.g., Ctnnb1, Myc, Gli3, Scyl2, Ccny, Daam1, Ppm1n, Rbpj, and Usp8). A key finding in this study was the downregulation of beta-catenin (Ctnnb1) gene expression in the SS-7 endometrium, suggesting that this treatment influences embryo-uterine dialogue by triggering a cascade of events leading to embryo maldevelopment. These data explain the proliferative defects in SS-7 embryos and suggest a novel mechanism of a porcine embryo-maternal crosstalk. Lay Summary Methods for porcine superovulation (increasing the number of ovulated oocytes per cycle) and estrus synchronization (grouping estrus sows on the same day) are available for assisted reproductive technologies, using hormonal treatments. The main goal of the present study was to understand how hormones used for these purposes influence gene expression patterns in the female reproductive tract (ovaries and endometrium). We observed that hormonal treatments (synchronization combined with superovulation) have the potential to alter ovarian and endometrial gene expression patterns, triggering improper follicle development and oocyte growth, and leading to abnormal embryonic development before implantation. Genes involved in two key metabolic pathways for embryo development (Wnt/beta-catenin and Notch signaling pathways) were dysregulated in reproductive tissues.
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| 5. |
- Johnsson, Martin
(författare)
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Problematizing Selection Mapping from an Animal Science Perspective
- 2022
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Ingår i: Journal of Animal Science. - : Oxford University Press (OUP). - 0021-8812 .- 1525-3163. ; 100, s. 15-16
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Selection mapping is a family of methods that use genome-wide genetic data to detect signatures of selection in the genome. The methods used to quantify these signatures range from relatively simple diversity statistics to complicated population genetic models or machine learning classifiers. Selection mapping of domestic and feral animals have identified signatures of selection in regions of the genome known to be associated with simple traits, large-effect alleles for complex traits, but also many regions of unknown significance. Selection mapping can be thought of as part of a broader move towards "natural history of the genome". As large amounts of genomic data are becoming available, there is a space for descriptive accounts of genome-wide data that aid hypothesis-generation and draw attention to striking features of the genome. However, selection mapping gives a particular, biased view of selection, and has methodological issues including dependence on population genetic parameters that are often unknown, and a bewildering array of analysis options. Therefore, we would do well to think hard about how and why we apply it.
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| 6. |
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| 7. |
- Manaig, Yron Joseph Yabut, et al.
(författare)
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Exon-intron split analysis reveals posttranscriptional regulatory signals induced by high and low n-6/n-3 polyunsaturated fatty acid ratio diets in piglets
- 2023
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Ingår i: Journal of Animal Science. - 0021-8812 .- 1525-3163. ; 101, s. 1-12
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Tidskriftsartikel (refereegranskat)abstract
- Polyunsaturated fatty acids (PUFA), such as omega-6 (n-6) and omega-3 (n-3), play a vital role in nutrient metabolism, inflammatory response, and gene regulation. microRNAs (miRNA), which can potentially degrade targeted messenger RNAs (mRNA) and/or inhibit their translation, might play a relevant role in PUFA-related changes in gene expression. Although differential expression analyses can provide a comprehensive picture of gene expression variation, they are unable to disentangle when in the mRNA life cycle the regulation of expression is taking place, including any putative functional miRNA-driven repression. To capture this, we used an exon–intron split analysis (EISA) approach to account for posttranscriptional changes in response to extreme values of n-6/n-3 PUFA ratio. Longissimus dorsi muscle samples of male and female piglets from sows fed with n-6/n-3 PUFA ratio of 13:1 (SOY) or 4:1 (LIN), were analyzed in a bidirectional contrast (LIN vs. SOY, SOY vs. LIN). Our results allowed the identification of genes showing strong posttranscriptional downregulation signals putatively targeted by significantly upregulated miRNA. Moreover, we identified genes primarily involved in the regulation of lipid-related metabolism and immune response, which may be associated with the pro- and anti-inflammatory functions of the n-6 and n-3 PUFA, respectively. EISA allowed us to uncover regulatory networks complementing canonical differential expression analyses, thus providing a more comprehensive view of muscle metabolic changes in response to PUFA concentration.
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| 8. |
- Müller, Cecilia, et al.
(författare)
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The effect of harvest time of forage on carbohydrate digestion in horses quantified by in vitro and mobile bag techniques
- 2023
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Ingår i: Journal of Animal Science. - : Oxford University Press (OUP). - 0021-8812 .- 1525-3163. ; 101
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Tidskriftsartikel (refereegranskat)abstract
- Grass species and harvesting time affect the nutrient content, in vitro and in vivo digestibility of forages measured with the mobile bag technique in horses. This study showed that harvesting time of forage had a larger effect on digestibility than grass species, and that fructans can potentially be digested precaecally.Lay Summary Feedstuffs contain different carbohydrate fractions that are digested in different parts of the gastrointestinal tract of horses. Grass for grazing or harvesting contains variable amounts of structural carbohydrates such as cellulose and hemi-cellulose (named fibres) and nonstructural carbohydrates which in temperate grass species include sugars and fructans (named water soluble carbohydrates (WSC)). This study quantified carbohydrate composition and digestion of six grass species (perennial ryegrass, timothy, smooth bromegrass, tall fescue, cocksfoot, and meadow fescue) harvested at three different times (early, medium, and late) and preserved as hay. In general, fiber content increased as the grasses matured, whereas WSC content varied to a large extent. In vitro fermentation using horse caecal fluid was used to quantify digestion of early and late cut grass samples of all species. Harvest time (early vs. late) had a larger effect on in vitro fermentation compared to the effect of grass species. Early and late harvested perennial ryegrass and cocksfoot were further selected for detailed studies of precaecal digestion in vivo as these species had highest and lowest WSC content. In general, cocksfoot was identified as grass species with low digestibility and low WSC concentration compared to the other species investigated.Carbohydrates in forages constitute an important part of the feed ration for all horses. The aim of the present study was to investigate the effect of harvest time on carbohydrate composition and digestion of various grass species. The experiment was divided into three parts 1) characterization of the chemical composition of experimental feeds (6 grass species: meadow fescue [MF], cocksfoot [CF], perennial ryegrass [PR], smooth bromegrass [SB], tall fescue [TF], and timothy [TI], and 3 harvest times: early, medium, and late first cut), 2) measurements of the in vitro digestion of selected experimental feeds (the 6 grass species, and 2 harvest times [early and late]) measured by in vitro gas production, and 3) in vivo digestion of selected experimental feeds (2 grass species: CF and PR, 2 harvest times [early and late]) measured by the mobile bag technique using caecum cannulated horses. An experimental field was established with plots containing each of the grass species in three replicate blocks. Grass samples were cut between 1200 and 1400 h at 4th of June (early first cut), 17th of June (medium first cut), and 1st of July (late first cut) and analyzed for crude protein (CP), neutral detergent fiber with heat stable amylase and free of residual ash (aNDFom) and water-soluble carbohydrates (WSC). The in vitro fermentation was investigated using the ANKOM RF gas production technique, where feeds were incubated for 48 h using horse caecal fluid as an inoculum. Gas production was modeled, and maximum gas production (MGP) was used to evaluate the potential digestibility of the feeds. Based on the chemical analyses and the in vitro experiment, early and late harvested CF and PR were selected for the in vivo experiment, which was conducted as a randomized 4 x 4 Latin square design including four periods, four horses and four feeds. In general, the CP content decreased whereas the aNDFom content increased as the grasses matured. The content of WSC increased in SB and TI, but decreased in CF, and fructans increased in SB, TI, PR, and TF as they matured. The in vitro MGP showed a clearer difference between harvest times than between grass species. Harvest time had larger effect on digestibility than grass species, and a high precaecal disappearance of the WSC fraction was measured by the mobile bag technique. Cocksfoot was identified as a grass species with potentially low digestibility and low WSC content and could potentially be used more for horses.
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| 9. |
- Rustas, Bengt-Ove, et al.
(författare)
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Extrusion of Grass Silage Increase Intake and Milk Yield in Dairy Cows
- 2021
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Ingår i: Journal of Animal Science. - : Oxford University Press (OUP). - 0021-8812 .- 1525-3163. ; 99, s. 176-176
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- This research evaluated effects of grass silage extrusion on dairy cow performance. A grass dominated (70% timothy, 26% meadow fescue, 3% red clover and 1% undefined) first cut ley was harvested on June 13, 2019, and 10 days later near Uppsala, Sweden (58°83′ N, 17°82′ E). Crops were wilted (45% DM for early cut, 50% DM for late cut), round baled and wrapped into plastic film for ensiling. At feeding out, bales were chopped in a TMR feeder, and a portion was processed in an extruder, where screws shear the material under pressure, for further particle size reduction and cell wall break up. Eight Swedish Red cows in two blocks (4 ruminally fistulated, 143 ± 38 DIM and 4 intact, 68 ± 10 DIM) were used in a Latin square design experiment with 4 periods of three weeks each and 4 treatments. The 2x2 factorial arrangement of treatments included silage from early or late harvest that was chopped or extruded. Silage was fed separately ad libitum and supplemented (daily amounts on an as fed basis) with 2 kg of soybean meal, a compound feed (6 kg for fistulated and 8 kg for intact cows), and 120 g of a mineral mix. Extrusion increased silage DMI (1.8 kg/d, P < 0.001) with greater effect at late harvest (P = 0.021 for interaction between processing and harvest) and milk yield (1.8 kg ECM/d, P = 0.004) with a tendency to greater effect at late harvest (P = 0.055). Extrusion depressed total tract OM digestibility (2.3 percentage points, P < 0.001), eating time (0.5 h/d, P = 0.014), rumination time (2.0 h/d, P < 0.001) and rumen pH (0.1 units, P = 0.008). Extrusion improves intake and milk production in dairy cows, despite depressed digestibility.
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| 10. |
- Rydhmer, Lotta, et al.
(författare)
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Effect of Genotype and Temperature-Humidity Index (THI) on milk yield of Ankole and its crossbreeds in Rwanda
- 2020
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Ingår i: Journal of Animal Science. - : Oxford University Press (OUP). - 0021-8812 .- 1525-3163. ; 98, s. 352-352
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The trend in crossbreeding the indigenous and resilient “Ankole” cattle with imported high performant breeds in Rwanda, believed to boost milk production while tempering on adaptive traits to local environment, leaves cautions on a profiling “genetic erosion” of Ankole. It is uncertain establishing whether new crossbreeds would acquire necessary resilience to parasites and climate stressors, where access to data records is unfordable. The objective of this study was to assess the environmental effect on milk yield (MY) in Ankole and its crossbreeds (with Holstein Frisian-AF, Jersey-AJ and Sahiwal-AS). Data of daily MY (61984 records; n = 188 cows), ambient temperature and relative humidity have been recorded from 2 research farms (Rubona-2.5536’ S, 29.6014’ and Songa-2.24’S, 29.46’E) located in the mid-altitude zone (1400–1500 m.a.s.l), on a period of 4 years (2014–2017). Fixed effects of Temperature-Humidity Index (THI, measure of Heat Stress), parity, genotype and station on MY have been investigated, using a General Linear Model (Y = μ+ p + g + s + rTHI + ℮; SAS 9.4). Results indicated an overall negative effect of THI threshold values on ML (P > 0.0001), with an aggregate decline slope of 0.12kg/day/THI. Ankole breed showed a lower ML decline slope (0.02 kg/day/THI) after the THI threshold of 75, suggesting its ability to resist in heat stress with relatively milder effect on its daily milk yield. However, although with important MY loss induced by THI as compared to Ankole, results suggested the ability of crossbreeds to withstand higher levels of THI thresholds evaluated at 76 with a decline slope of 0.08kg/day/THI and 0.12kg/day/THI, respectively for AH and AJ, while THI thresholds for AS was found at 77 (0.12kg/day/THI). The observed relative resistance of Ankole crossbreds to higher heat stress levels would suggest a possible heterosis effect.
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| 11. |
- Spörndly-Nees, Ellinor, et al.
(författare)
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Chemical composition of horse hooves with functional qualities for competing barefoot
- 2023
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Ingår i: Journal of Animal Science. - 0021-8812 .- 1525-3163. ; 101
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Tidskriftsartikel (refereegranskat)abstract
- Barefoot racing is a common practice within the harness racing industry, but not all horses have hooves of sufficient quality to race sustainably without shoes. There is currently no objective approach available to assess whether a horse’s hooves are suitable for barefoot racing, raising animal welfare issues if trainers misjudge the functional qualities of hooves. This study compared chemical composition of the hoof wall and fatty acid (FA) composition of the digital cushion in a group of horses that had raced barefoot often (RB) and a group of horses that could not race barefoot and therefore raced with shoes (RS). Trimmings from the hind hoof wall were collected from the lateral quarters in one sub-cohort postmortem and in another sub-cohort of live horses and analyzed for macro- and microelements, nitrogen, dry matter (DM), and total and free amino acid content. For the postmortem horses, samples of the digital cushion were also collected and analyzed for total and free FAs. RB horses had lower concentrations of copper in the hoof wall (17.5 ± 3.9 vs. 32.8 ± 4.7 mg/kg DM, P = 0.02) than RS horses. RB horses also tended (P < 0.1) to have higher concentrations of nitrogen (164.2 ± 0.2 vs. 163.5 ± 0.3 g/kg DM) and sulfur (22.9 ± 0.2 vs. 22.3 ± 0.3 g/kg DM). RB horses had higher hoof wall concentrations of arginine (10.51 ± 0.05 vs. 10.34 ± 0.06 g/100 g DM, P = 0.03) and showed a trend (P < 0.1) for higher hoof wall concentrations of cysteine (6.14 ± 0.10 vs. 5.82 ± 0.13 g/100 g DM) and proline (4.62 ± 0.05 vs. 4.49 ± 0.06 g/100 g DM). There were no differences between the groups for any other element or amino acid analyzed. There were also no differences between the two groups in terms of FA composition of the digital cushion. These results indicate that chemical composition, especially with respect to copper, arginine, nitrogen, sulfur, cysteine, and proline, may be important for the functional qualities of the hoof capsule and the ability to race barefoot without wearing the hoof down. However, chemical analysis of hoof wall tissue and of the fat content of the digital cushion does not seem to be a definitive method for distinguishing horses that have hooves suitable for barefoot racing from those that do not.
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