Mireia Blanco

Aim of study: To evaluate the effect of the type of male castration (surgical vs. immunological) on the characteristics of Teruel dry-cured hams. Area of study: Teruel and Zaragoza (Spain). Material and methods: A total of 14 dry-cured hams from Duroc × (Landrace × Large White) male pigs intended for the Spanish Protected Designation of Origin ˈTeruel hamˈ were used. Half of them belonged to surgical castrated males (SCM) and the other half to immunocastrated males (IM). Ham weight losses during processing, physical and chemical characteristics were analyzed. Main results: There were no differences (p>0.05) due to the type of castration in ham weight losses throughout processing, thickness of subcutaneous fat, marbling, maximum stress and intramuscular fatty acid profile. However, hams from IM presented lower (p<0.05) chroma than those from SCM. The type of castration had limited influence on chemical composition; only potassium nitrate and retinol contents were affected (p<0.05), being lower in IM than in SCM. For volatile compounds, IM showed lower (p<0.05) percentages of total alcohols and sulfur compounds and higher (p=0.012) proportion of total acids than SCM. All the hams had negligible androstenone content but IM presented higher (p<0.05) skatole and indole concentrations than SCM, being these levels low. Research highlights: The type of castration in male pigs seems to have scarce influence on the quality of Teruel dry-cured hams, and therefore, immunocastration could be considered as a possible alternative to surgical castration.

Background: Sainfoin (Onobrychis viciifolia) and sulla (Hedysarum coronarium) are forage legumes usually preserved to optimize their utilization as feedstuffs. However, the method of preservation modifies the chemical composition differently in both legume species. Secondary compounds (such as proanthocyanidins, fatty acids, carotenoids and tocopherols) present in forages affect the quality of animal products. Therefore, the effect of preservation on the contents of secondary compounds should be investigated. Accoridngly, samples of sainfoin and sulla were directly freeze‐dried (fresh), dried at ambient temperature (hay) and vacuum‐packaged for 82 days (silage).Results: In both legumes, the total fatty acid and C18:3 n‐3 contents decreased and C16:0 increased with preservation (P < 0.001), with a greater effect for the hays than for the silages. For both legumes, the lutein, neoxanthin and violaxanthin contents decreased to a greater extent in the silages than in the hays (P < 0.001). Both hays exhibited the lowest β‐carotene concentrations (P < 0.001). The α‐tocopherol contents decreased in hays, but not in silages, compared to the fresh forages of both legumes (P < 0.001). The antioxidant activities were lower in the silages than in the hays and fresh forages (P < 0.001) and were very strongly related to the contents of polyphenols and proanthocyanidins (P < 0.001).Conclusion: Haymaking affected the fatty acid, carotenoid and α‐tocopherol contents to a greater extent but had a lesser effect on the antioxidant activities than silage‐making, which were very strongly related to their contents of polyphenols and proanthocyanidins. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Sainfoin (Onobrychis viciifolia) is a forage legume with a medium content of proanthocyanidins (PAC), which may affect animal performance and product quality. The objective of the present study was to assess the effect of PAC from sainfoin fed to dams, using polyethylene glycol (PEG) as a blocking agent, on the performance and carcass and meat quality of their suckling male lambs. After lambing, twenty lactating dams were fed fresh sainfoin ad libitum plus 200 g per day of barley; ten were orally dosed with water (Sainfoin), and ten were dosed orally with a water dilution of 100 g PEG (Sainfoin + PEG). Their lambs (4.1 ± 0.64 kg at birth) suckled ad libitum until they reached the target slaughter weight of 10–12 kg. The presence of PAC in the dams’ diet did not affect the growth, blood metabolites and carcass weight and fatness of the suckling lambs but decreased the lightness of caudal fat (p < 0.05) and increased the weight of the digestive compartments (p < 0.05). Regarding the meat characteristics, PAC only decreased polyphenols content (p < 0.05). In conclusion, the presence of PAC in the dams’ diet had not significant effects on the performance and product quality of their suckling lambs.

The use of pea (Pisum sativum) has been recommended to replace soybean meal in the diet of ruminants, but it may affect meat quality. The aim of this study was to evaluate the effect of the proportion of pea (0%, 10%, 20% and 30%) in fattening concentrates fed to light lambs for 41 days on carcass colour and on the meat quality. Pea inclusion affected neither the colour of the lamb carcasses nor affected most of the parameters of the meat quality. However, the inclusion of pea affected the cholesterol content, and the 20%pea concentrate yielded meat with greater cholesterol contents than the 30%pea concentrate did (p < 0.05). The inclusion of pea had minor effects on individual FAs but affected the total saturated fatty acids (p < 0.01) and the thrombogenicity index (p < 0.05). A greater total saturated fatty acid content was recorded for the 20%pea concentrate than for the rest of the concentrates, and a greater thrombogenicity index was recorded for the 20% concentrate than for the 10%pea concentrate. The results indicated the viability of the inclusion of pea in the fattening concentrate of light lambs without impairing meat quality, with the 30%pea concentrate being the most suitable to reduce the soya-dependency.

Context: Improving feed efficiency in livestock production is of great importance to reduce feeding costs. Aims: To examine the relationship between ruminal microbiota and variation in feed efficiency in beef cattle fed concentrate-based diets. Methods: Residual feed intake of 389 fattening bulls, supplied with corn-based concentrate and forage ad libitum, was used to estimate animals’ feed efficiency. Faeces and ruminal fluid samples, from 48 bulls chosen at random, were collected to estimate their forage intake and to determine their apparent digestibility, ruminal fermentation and microbiota. Those animals with extreme values of feed efficiency (high-efficiency (HE, n = 12) and low-efficiency (LE, n = 13)) were subjected to further comparisons. Alpha biodiversity was calculated on the basis of the normalised sequence data. Beta diversity was approached through performing a canonical correspondence analysis based on log-transformed sequence data. Genera differential abundance was tested with an ANOVA-like differential expression analysis and genera interactions were determined applying the sparse correlations for compositional data technique. Key results: No differences in dry matter intake were found between the two categories of feed efficiency (P = 0.699); however, HE animals had higher apparent digestibility of dry matter (P = 0.002), organic matter (P = 0.003) and crude protein (P = 0.043). The concentration of volatile fatty acids was unaffected by feed efficiency (P = 0.676) but butyrate proportion increased with time in LE animals (P = 0.047). Ruminal microbiota was different between HE and LE animals (P = 0.022); both α biodiversity and genera network connectance increased with time in LE bulls (P = 0.005 for Shannon index and P = 0.020 for Simpson index), which suggests that LE animals hosted a more robust ruminal microbiota. Certain genera usually related to high energy loss through methane production were found to establish more connections with other genera in LE animals’ rumen than in HE ones. Microbiota function capability suggested that methane metabolism was decreased in HE finishing bulls. Conclusions: Rumen microbiota was associated with feed efficiency phenotypes in fattening bulls fed concentrate-based diets. Implications: The possible trade-off between feed efficiency and robustness of ruminal microbiota should be taken into account for the optimisation of cattle production, especially in systems with intrinsic characteristics that may constitute a disturbance to rumen microbial community.

BACKGROUND: The objective of this study was to evaluate the effect of the proportion of pea (0%, 10%, 20%, and 30%), as a partial replacement for soybean meal (SBM) in the fattening concentrate, on ruminal fermentation in lambs. Gas and methane (CH₄) production, in vitro dry matter degradability (IVDMD), ammonia (NH₃‐N), and volatile fatty acid (VFA) production after 24 h of incubation were evaluated. The concentrates were also incubated in the rumen of the wethers for 2, 4, 6, 8, 12, and 24 h to evaluate the effects of pea inclusion on in situ dry matter degradability (DMD), organic matter degradability (OMD), nitrogen degradability (ND), NH₃‐N, and VFA production.RESULTS: In the in vitro assay, the inclusion of pea only affected gas production (mL day⁻¹ degraded dry matter), CH₄ production (mL day⁻¹ degraded dry matter), and IVDMD (P < 0.05), and tended to affect NH₃‐N content (P < 0.10) without affecting VFA production. In the in situ assay, the inclusion of pea increased DMD, OMD, and ND linearly (P < 0.001), whereas pea inclusion decreased NH₃‐N content linearly (P < 0.05). Neither total VFA production nor the proportion of acetic acid were affected by pea inclusion (P > 0.05), but the propionic proportion increased with the proportion of pea included.CONCLUSIONS: The best level of pea inclusion in the concentrate could not be established based on the results of this study. However, the results showed that the inclusion of pea provides a good alternative protein source. © 2020 Society of Chemical Industry