Livestock Science最新文献

Thoroughbred breeding holds significant economic importance on a global scale and Argentina is a prominent participant in this industry. Suboptimal growth of Thoroughbred foals below their genetic potential could have consequences on their athletic ability. But, unlike some livestock, maximal growth in horses is not advantageous, as it can lead to skeletal problems. Therefore, the meticulous monitoring of foal growth is indispensable for effective horse breeding. This longitudinal study examined 18,639 weight records obtained from 2631 foals (0–19 months old) across an 11-year period. The objective of this study was to identify the most suitable models for fitting growth curves of pasture-raised Thoroughbred foals. Seven model was separately fitted to the records using SAS's NLIN procedures. The goodness of fit of the models was based on Akaike's Information Criterion, Mean Square Error and Root Mean Square Error statistics. The study concluded that the Polynomial G3 model best describes the growth patterns of Thoroughbred foals in Pampas region, providing the final equation for predicting the average population weight of these foals based on their age in months: Body weight = 58.8 + 41.65 t − 1.82 t²+ 0.041 t³ (where t is age in months). This model's accuracy was consistent across sex, eliminating the need for separate models based on sex. This equation allows us to estimate the foals' body weight as a function of their age, providing a valuable tool for monitoring their growth and development. These insights have the potential to enhance breeding practices and optimize management strategies within horse production systems in a region renowned for its pasture-based management approach.

Scaling-up fungal pretreatment of lignocellulose biomass (LCB) for ruminant nutrition has become a major research challenge in recent years. This study systematically investigated the effectiveness of fungal (Pleurotus ostreatus) pretreatment (for 30 days under solid state fermentation (SSF)) of large quantities (8400 kg) of lime-pasteurized wheat straw, in terms of improvement in nutritional value, in vitro ruminal fermentation characteristics and methane (CH₄) production potential. We further investigated the effects of stepwise replacement of untreated wheat straw (UTWS) with the lime pasteurized P. ostreatus treated wheat straw (PTWS) on dry matter intake (DMI), apparent total tract digestibility, production performance, CH₄ emission and feed efficiency of lactating dairy cows. The results revealed that PTWS had lower lignin (P < 0.001), hemicellulose (P < 0.001) and cellulose (P < 0.05) contents and higher crude protein (CP; P < 0.001) content and cellulose to lignin ratio (P < 0.01), as compared to UTWS. The PTWS had higher in vitro DM digestibility (IVDMD; P < 0.001), total gas production (IVGP; P < 0.01), total volatile fatty acids (VFAs, P < 0.01) and propionate (P < 0.05) concentration, and lower (P < 0.05) pH and CH₄ gas production during 72 h in vitro fermentation. Notably, the fungus degraded 33.3 % lignin at the expense of 6.56 % cellulose, and markedly increased CP content (46.3 %), IVDMD (20.2 %), IVGP (16.8 %) and VFAs (10.0 %) production, and decreased CH₄ production (10.3 %). The aflatoxin B₁ concentration of PTWS was <5.0 µg/kg, and mycelium concentration was 181.9 mg/kg DM, reflecting safe and effective tretment of the straw. Replacement of 32 % UTWS in total mixed ration with the PTWS, increased DMI (0.84 kg/day; P = 0.01), apparent total tract DM digestibility (5.5 g/100 g; P < 0.05) and milk yield (1.17 liter/day; P = 0.032), and decreased CH₄ emission (1.45 g/kg DMI; P < 0.05). In conclusion, hydrated lime can replace traditional high-tech pasteurization methods for the fungal pretreatment of LCB, and present prospects for scaling up the process for ruminant nutrition.

The cheese core has a lower oxygen saturation and salinity and a higher acidity than the rind, but there is controversy about the incidence of such factors on the magnitude of microbial diversity. The goal of the current work was to investigate the existence of differences in α-diversity between the core, middle part, and rind of six Spanish commercial cheeses through a sequencing approach. To this end, we have collected rind, middle part, and core samples from fresh (H and M), soft semi-ripened (C and P), hard semi-ripened (B) and semi-hard aged (G) goat cheeses. After purifying deoxyribonucleic acid from these 18 samples, the V3-V4 ultravariable region of the 16S rRNA gene was sequenced. The analysis of microbial composition revealed that lactic acid bacteria from the genera Lactococcus, Lactobacillus, Streptococcus, and Leuconostoc are predominant in all six goat cheeses. Furthermore, we identified several psychrophilic taxa often associated with the post-pasteurization contamination of refrigerated milk. Comparison of three α-diversity estimators (Chao1, Shannon and Faith's phylogenetic diversity indices) of microbiota in the core, middle part, and rind of all six goat cheeses did not reveal substantial differences, being only significant (at the nominal level) the comparison of rind vs middle part for the Shannon index (P-value = 0.031). Moreover, the construction of a dendrogram based on Aitchison distances revealed that cheese samples cluster according to their manufacturing characteristics, with a clear distinction between fresh vs semi-ripened or aged cheeses. We conclude that the magnitude of microbial α-diversity in the cheese core is similar to that in the rind despite their different physicochemical attributes. This result could be because physicochemical differences between cheese compartments are often attenuated during cheese ripening.

Animal diseases pose a significant threat to the global livestock industry, with severe economic consequences. To minimize this impact, farmers employ various preventative measures, with hoof trimming being the most common method for addressing hoof disorders. This study analysed the economic effects of hoof trimming on dairy farms, using a panel dataset containing three years of hoof health data across Finland. This was an observational study that also addressed the issue with unavoidable confounders. To reduce bias, inverse propensity score weighting (IPW) was used, which assigned weights based on the probability density function of treatment frequency. By reweighting the data, this study improved the validity of the causal inference in the presence of confounding unobserved variables. The results of the study indicated that both infectious and non-infectious hoof disorders were notable on dairy farms in Finland. Furthermore, frequency of hoof trimming was influenced by several factors, including hoof health, farm characteristics, and management decisions. The analysis suggested a U-shaped relationship between hoof trimming and farms' profitability. Although the profitability ratio initially decreased, it increased after reaching a hoof trimming level of 97 %. The study highlighted how important systematic and regular hoof trimming is to maintain profitability.

Efforts to mitigate enteric methane (CH₄) emission from ruminants by using the red macroalgae Asparagopsis taxiformis (AT) have demonstrated promising results both in vitro and in vivo. We assessed the effects of wild harvested and freeze-dried AT inclusion in the grass silage-based diets of Norwegian Red dairy cows on feed intake, milk yield and composition, rumen fermentation and CH₄ emission. Fifteen (9 rumen cannulated and 6 intact) multiparous cows with an average (±SD) covariate period milk yield (MY) of 33.0 (3.8) kg/day were used in the experiment. The cows were divided into three groups (n = 5) after blocking for cannulation, and initial MY. After feeding on a common diet for 21 days (i.e., Covariate period), the groups were randomly allocated to three treatments: Control (no seaweed), 0.125%AT (Control + 0.125%AT, on organic matter (OM) basis) and 0.25%AT (Control + 0.25%AT, on OM basis). The cows were adapted to their diets for 13 days, followed by 39 experimental days for data collection. Inclusion of AT at 0.125% level did not affect dry matter intake (DMI, kg/d) but signicantly reduced both MY and energy corrected milk yield (ECM, kg/d) (P < 0.05) with a tendency for lower CH₄ production (g/d) relative to the control group. Dry matter intake, ECM and CH₄ production were reduced (P < 0.05) by 0.25%AT inclusion relative to the Control group. Apparent total tract nutrient digestibility (%), ECM per kg DMI, CH₄ yield (g CH₄/kg DMI) and CH₄ intensity (g CH₄/kg ECM) were not affected by AT inclusion. Inclusion of AT, at both levels, significantly reduced (P < 0.05) ruminal fluid total short chain fatty acids and molar proportions of actate, while increasing (P < 0.05) the molar proportion of propionate and isovalerate. Inclusion of AT decreased contents (%) of milk fat (P = 0.018) and protein (P = 0.010) resulting in significanly lower fat and protein yields. Lactose content (%) was higher for the AT groups (P = 0.021) but this did not compensate for lower MY resulting in lower milk lactose yield. Milk iodine content increased in a dose dependent manner with AT inclusion. In conclusion, AT inclusion at 0.25% level reduced CH₄ emission from dairy cows with a grass silage-based diets. However, the reduced DMI for the 0.25%AT group along with reduced MY and elevated milk iodine content for both AT groups, for this particular harvest of AT, would suggest possible constraints for large scale inclusion of AT in dairy cow production.

The objective of this study was to investigate the effect of administering a blend of cinnamaldehyde, eugenol, and capsicum oleoresin (CEC) to lactating dairy cattle for 105 days (i.e., 15 weeks) on enteric methane emission, feed intake, milk yield and composition, and body weight. The experiment utilized 40 Nordic Red lactating dairy cows (97 ± 59 days in milk at the start of the trial; mean ± SD) blocked into pairs based on dry matter intake (DMI), milk yield, parity, and lactation stage. Cows within block were randomly assigned to 1 of 2 dietary treatments; 1) CEC supplemented at 1.2 g/cow/d or 2) a control diet without CEC. Cows were offered ad libitum a basal diet of grass silage and concentrate fed separately in a 55:45 forage to concentrate ratio on a dry matter (DM) basis. A GreenFeed system was used to measure emissions of carbon dioxide (CO₂), methane (CH₄) and hydrogen (H₂). Supplementation with CEC decreased daily CH₄ production (g/d; 3.4%) and yield (g/kg DMI; 4.2%) and daily CO₂ production and yield (3.3% and 4.0%, respectively) whereas CH₄ and CO₂ intensities were not affected by treatment. Daily CEC supplementation tended to reduce H₂ production and intensity by 21% compared with control. Additionally, feed intake, milk production, milk composition, body weight, and body condition score were not influenced by dietary CEC supplementation. These results indicate that CEC supplementation can reduce CH₄ production without affecting performance of lactating dairy cows.

The objective of the present study was to evaluate the performance of primi- and multiparous dairy cows fed diets with ground or rolled fava beans (FB). A total of 96 Danish Holstein cows (48 primi- and 48 multiparous) were used in a randomized block design lasting 4 weeks. Within parity group, cows were blocked according to their milk yield in 6 blocks with 8 cows each and two cows from each block were distributed in pens where they were assigned randomly one of the two experimental diets. The diets were based on a total mix ration (TMR) composed of 52.6 % forage and 47.4 % concentrate (DM basis), differing only in the particle size of FB (geometric mean diameters of 1.02 and 3.52 mm for ground and rolled FB, respectively). Feed intake, milk production, and milk composition were determined during the last 8 days of the experimental period; none of these differed between treatments except for a higher (P = 0.01) milk N efficiency (% of N intake) and milk urea content with ground FB compared with rolled FB. Additionally, feces and ruminal fluid were collected from a group of 24 multiparous cows to determine fecal starch content and ruminal volatile fatty acids (VFAs). The fecal starch concentration was greater with rolled FB showing a reduced starch digestion, whereas ruminal VFA proportions generally did not differ between treatments. In conclusion, the lactation performance of dairy cows appeared not to be affected by grinding or rolling of FB with a 20 % FB inclusion in the DM diet, even though total tract starch digestion was reduced with greater FB particle size.

This study investigates the environmental sensitivity and sexual dimorphism in the genetic parameters of weaning weight (WW) in Nelore beef cattle. Five reaction norms models were employed to analyze the 148,131 WW records, considering different definitions of the environmental descriptor (ED). (Co)variance components and genetic parameters were separately estimated for males and females. Results reveal substantial sexual dimorphism in various parameters. Significant divergence across sexes was observed for environmental sensitivity, with males showing an increased response to favorable environments while females genetically responded better to more challenging environments. Including sex in defining the ED can inflate the estimated breeding values of sires with a higher number of male progeny records, highlighting the importance of choosing a reliable ED in analyses of traits influenced by sexual dimorphism and genotype-by-environment interaction (G × E). The observed sexual dimorphism and environmental sensitivity underscore the complexity of genetic evaluation of WW in beef cattle populations, with implications for selection strategies. The findings suggest that a sex-separated trait analysis considering G × E effects is most appropriate for genetic evaluations of WW. However, a simpler single-trait model excluding sex from the ED definition yielded a higher coincidence of selected sires with the sex-separated analysis. In conclusion, understanding sexual dimorphism and environmental sensitivity is crucial for genetic evaluations and selection decisions in beef cattle breeding programs, emphasizing the need for careful model selection and ED definition.

Lipids are fundamental to the structure and function of the brain, and their fatty acids (FA) composition is rich in polyunsaturated fatty acids (PUFA), which have protective effects and modulate gene transcription. For nutrigenomics studies, pigs (Sus scrofa) have been widely used as a biomedical model. Thus, the aimed to investigate whether different dietary oil sources modify the pig brain's lipid and transcriptomic profile. A 98-day study was performed using fifty-four male pigs. Treatments consisted of corn-soybean meal diets containing 3 % of soybean oil (SOY), canola oil (CO), or fish oil (FO). Total mRNA was extracted for sequencing. As a result, feeding diets with different oil sources affected the percentage of some FA. Palmitic acid showed a greater concentration in diets containing SOY with 27.037 %. Oleic acid and eicosenoic acid, showed a greater concentration in diets containing SOY, with 30.968 % and 2.096 %, respectively; and, total PUFA showed a better concentration in diets containing SOY and FO, with 11.685 % and 12.150 %, respectively. After quality control, considering the total reads obtained for the three groups, 94.87% were mapped against the reference genome SScrofa11.1. A comparison of gene expression between the groups of pigs was carried out by using the DESeq2 statistical package (R/Bioconductor). From SOY vs CO comparison, five differentially expressed genes (DEG, FDR < 0.05) were identified, from SOY vs FO forty-four DEG were verified, and from CO vs FO thirty-nine DEG were found. The functional enrichment analysis resulted in pathway maps (P < 0.05) related to apoptosis and cell proliferation, obesity and type 2 diabetes, neurophysiological process, and inflammation. The networks were associated with signal transduction, calcium transport, and oxidative stress. Overall, the results showed that diets with different oil sources could affect some brain tissue parameters and may help guide future research on the availability of dietary FA in the brain.

Prepartum shearing has been associated with increased lamb survival under pastoral conditions. This research aimed to evaluate the effects of early and late prepartum shearing in gestating Corriedale ewes on the metabolic profile and placental parameters of the ewes and how these changes affect the productive parameters of their lambs. On day 70 of gestation, 37 ewes carrying a single foetus were randomly divided into three groups: ewes sheared at day 70 of gestation (early, PS70, n = 12), sheared at day 110 of gestation (late, PS110, n = 12), and ewes unsheared at prepartum (US, n = 13, control group). Energy metabolism (glycaemia, insulin, NEFA, and BHB) and placental parameters (placental weight, number, and characteristics of cotyledons, and placental efficiency) were evaluated in the ewes. Live weight, morphometric measurements, and body composition were determined in the lambs. Prepartum shearing performed on different days (early and late) caused changes in energy metabolism, leading to a decrease in serum insulin and an increase in NEFA and BHB blood values. Early prepartum shearing increased placental weight and the number and weight of the 2–3 cm-cotyledons, while late prepartum shearing increased placental weight and placental efficiency and only changed the weight of the 2–3 cm-cotyledons. Prepartum shearing on both days caused an increase in lamb birth weight. Therefore, prepartum shearing caused changes in the metabolic profile and placenta of the ewes, which resulted in increased weight and development of lambs at birth.