Feeding high-grain diets is a common practice in intensive ruminant production systems to meet animal energy requirements and maximize feed efficiency. One of the consequences of these diets is trans (t)10 shifted ruminal biohydrogenation, which includes increased formation of t10-18:1 and t10, cis (c)12-conjugated linoleic acid (t10, c12-CLA) at the expense of t11-18:1 and c9, t11-CLA. In dairy cows, the t10 shift has been associated with milk fat depression. In beef cattle, the t10 shift has not been associated with negative effects on animal performance or marbling fat deposition; however, it may negatively impact meat fat eating quality by decreasing its cis monounsaturated fatty acid to saturated fatty acid ratio. Finally, the t10 shift increases t10-18:1 accumulation in ruminant-derived foods (dairy, beef, and lamb), which at high enough levels may compromise the nutritional quality of these foods. The present review will cover our current understanding of the rumen microbes involved in the t10 shift and its implications for milk fat synthesis and beef fat quality.

This study aimed to estimate the genetic parameters for reproductive and early performance traits in Vietnam-purebred Landrace pigs. Traits analysed included the total number of pigs born (TB), number of pigs born alive (NBA), number of weaned pigs (NW), individual birth weight (BW), litter birth weight (LBW), individual weaning weight (WW), and litter weaning weight (LWW). This analysis was based on 5294 farrowing records collected from 2013 to 2019 from 1500 Landrace sows across three locations in Vietnam. Genetic parameters were estimated using ASReml-R. Heritability estimates for reproduction traits were negligible, below 0.10, ranging from 0.019 ± 0.012 to 0.071 ± 0.014, with repeatability ranging from 0.019 ± 0.014 to 0.152 ± 0.016. The genetic correlations ranged from −0.788 ± 0.09 to 0.993 ± 0.163, with the highest between IBW and LWW and the lowest between TB and IBW. NBA showed positive and moderate to high correlations with other traits, except for a negative correlation with IBW. Phenotypic correlations among reproductive traits ranged from −0.42 ± 0.013 to 0.879 ± 0.004. Negative phenotypic correlations were observed between TB, NBA, and NW with IBW and IWW, while positive correlations were observed with LBW and LWW. In conclusion, the heritability for reproductive performance and early growth traits in Vietnam-purebred Landrace pigs is negligible, indicating limited genetic progress from direct selection.

A study was conducted to investigate the effects of functional amino acid (AA) blend dietary supplementation with different feeding regimens on growth performance and protein utilization in weaned pigs. Pigs were fed either a standard (STD) diet or a supplemental (SUP) diet, which included an additional AA blend in the STD diet. Ninety-six piglets (6.51 ± 0.34 kg) were randomly assigned to one of four feeding regimens: a STD diet throughout the experiment, or a SUP diet for phase I (SUP7), until phase II (SUP21), or until phase III (SUP35). During phase I, pigs fed an SUP diet exhibited a greater (P < 0.05) average daily gain and gain-to-feed ratio (G:F) than those fed the STD diet. Pigs in the SUP35 group had a higher (P < 0.05) G:F than those in the SUP7 group. Pigs in the SUP21 and SUP35 groups had greater (P < 0.05) digestibility of N than those in the SUP7 group. Pigs in the SUP35 group had upregulated (P < 0.05) mRNA encoding mammalian targets of rapamycin and cationic AA transporter1 in longissimus dorsi than those in the SUP21 group. Feeding the SUP diet throughout the 5-week nursery phase is recommended to achieve optimal growth performance and protein metabolism.

The aim was to determine the effects of supplementing increasing doses of phytase alone or in combination with a multi-carbohydrase blend to a phosphorus (P)-deficient diet for nursery pigs on growth performance, nutrient digestibility, and metacarpal bone characteristics. A total of 192 weaned pigs (7.7 ± 0.05 kg) were allotted to one of eight dietary treatments each with eight replicates in a randomized complete block design based on initial body weight. Fecal samples (days 18, 19, and 20) and metacarpal bones (day 21) were collected to determine apparent total tract digestibility (ATTD) of energy and nutrients and bone mineralization, respectively. During week 3 and overall period, increasing doses of phytase quadratically increased (P < 0.05) average daily gain. The ATTD of ash and P quadratically increased (P < 0.05) when doses of phytase increased. Phytase had quadratic (P < 0.05) effects by increasing fat-free dry weight, ash content, and P in metacarpal bone. In conclusion, increasing levels of phytase quadratically improved growth performance in week 2, nutrient digestibility, and bone traits of pigs fed a P-deficient diet. In general, however, there was no effect of multi-carbohydrase supplementation on growth performance and metacarpal characteristics in nursery pigs.

The objective of this study was to identify potential genetic variants and positional candidate genes associated with growth and feed efficiency traits in American mink. Genome-wide association studies (GWAS) were performed using deregressed estimated breeding values of 1037–1872 individuals (as pseudophenotypes), genotyped with the Affymetrix Mink 70K single nucleotide polymorphism (SNP) array. A total of 42 SNPs located on 11 different chromosomes were significantly (false discovery rate < 0.01) associated with six growth and feed efficiency traits. Furthermore, 153 genes were identified within 1-Mb windows flanking these significant SNPs. Several positional candidate genes such as TUBB, CDKN1A, SRSF3, GPRC6A, RFX6, and KPNA5 were previously associated with feed efficiency and growth traits in other livestock species. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses revealed that these genes were involved in lipid metabolism, hormone signaling and regulation, and muscle development. To our knowledge, this is the first GWAS to identify genetic variants and biological mechanisms associated with growth and feed efficiency traits in American mink. These findings provide a biological foundation for improving these traits using genomic selection programs to select more efficient mink.

Behaviour, heart rate (HR), and blood lactate concentration of 144 pigs, equally distributed into lighter (L, 122 kg on average) and heavier (H, 153 kg on average) groups, were assessed to study the effects of slaughter weight on pigs’ response to a simulated loading and unloading procedure using four ramp configurations, i.e., 0° (level ramp), 15° slope and 1.66 m length, 15° slope and 2.71 m length (15°LO), and 25° slope and 1.66 m. No interaction was found between ramp configuration and slaughter weight (P > 0.10). The frequencies of pigs’ slips or falls (P = 0.01) increased on sloped ramps compared to the floor level (P_adj < 0.05), and pigs jumped-off more from the 25° than the 15°LO ramp (P_adj = 0.05). Pigs negotiating the 25° slope ramp presented a higher concentration of blood lactate than those walking at the floor level (P = 0.02). When compared to L pigs, H pigs were more reluctant to move (P = 0.05), and presented higher increments of HR (ΔHR) during handling (P = 0.03). In conclusion, heavier pigs were more difficult to handle, regardless of the ramp steepness, which alone reduced ease of handling and affected the physiological condition of pigs.

This study investigated factors influencing heifer replacement and cow–calf profitability using 361 cows (born 2011–2018) at the Lacombe Research and Development Centre, Alberta, Canada. Profitability was measured by marginal returns (MR) incorporating feed costs, heifer opportunity cost, calf and cull revenues, and a premium for cows retained in the herd. The study evaluated the linear effects of lifetime productivity, feed efficiency (residual feed intake adjusted for off-test backfat thickness; RFI_fat), and genomic retained heterozygosity, an indicator of heterosis, on MR, feed costs, total costs, and net revenue (NR). Lifetime productivity, defined by the cumulative weight of calves weaned, was positively associated with MR and NR (P < 0.01). RFI_fat influenced total cost, MR, and NR (P < 0.05), with MR improved by $168.50 cow⁻¹ year⁻¹ for each unit decrease in RFI_fat, although regression and group mean comparisons were not fully consistent. Genomic retained heterozygosity positively impacted MR and NR, with a 10% increase enhanced MR and NR by $21.80 and $20.50 cow⁻¹ year⁻¹, respectively. Cow breed type did not affect longevity, MR, or NR. In conclusion, RFI_fat and genomic diversity were important factors to consider in heifer replacement decisions when lifetime DMI was estimated as described in the present study.

This study aimed to quantify the relationship between residual feed intake (RFI) measured in 500 heifers and subsequently as mid-gestation cows at the Roy Berg Kinsella Research Station (KIN; n = 227) and Lacombe Research and Development Centre (LRDC; n = 273). Heifers were initially tested for RFI adjusted for end of test rib fat (RFI_fat) at 8–12 months of age and then again as 3-year-old first-calf heifers at KIN and as 4–13-year-old cows at LRDC. Heifer RFI_fat measured in drylot on a forage diet was associated (R² > 0.53; P < 0.001) with RFI_fat measured again as older cows. Each 1 kg DM day⁻¹ change in heifer RFI_fat equaled 0.48 ± 0.10 and 0.75 ± 0.19 kg DM day⁻¹ change in cow RFI_fat for KIN and LRDC, respectively. Linear effects were also reported for RFI_fat component traits, where DMI (P < 0.001), ADG (P < 0.060), mid-test metabolic weight (P < 0.001), and end of test rib fat (P < 0.001) measured as heifers were related when measured again as older cows. In addition, the linear effects of heifer RFI_fat on cow RFI_fat were constant across cow age groups from 4–10 years of age. These results show that selection for RFI in heifers will result in cows that are also more feed efficient.

The objective of this in vitro study was to assess the effects of high-carvacrol oregano oil (ORE; 50 g/kg oregano oil, 800–802 g/kg carvacrol), on microbial fermentation and CH₄ production. In the experiment (a complete randomized block design), treatments included a negative control (CTL, no additive), a positive control (monensin, MON, 10 mg/L of culture fluid), and ORE (20, 40, 80, 120, 200, 160, and 1000 mg/L of culture fluid). Compared with CTL, MON shifted (p < 0.05) volatile fatty acid (VFA) profile from acetate and butyrate to propionate production, thereby reducing (p < 0.05) CH4 production (−26%). Monensin decreased (p < 0.05) NH3 and branched-chain VFA concentrations. Of the doses evaluated, only the highest dose (1000 mg/L) affected ruminal microbial fermentation and CH4 production. At this dose, ORE reduced (p < 0.05) gas production, total VFA, acetate, propionate and NH₃ concentrations, and CH₄ production (−22%). The reduced gas production and total VFA is an indication of feed digestion inhibition. These results suggest that ORE may decrease CH₄ production and improve ruminal N utilization. However, these findings need to be validated in vivo to determine the optimal dose to benefit from the positive effects while avoiding the negative impact of ORE on feed digestion.

Focus remains on reducing the excretion of surplus zinc (Zn) from pigs through manure due to environmental and public health concerns. Growing–finishing pigs may need less dietary Zn than current EU legislation allows and what is typically applied on farms. The aim of this study was to evaluate the effect of three dietary Zn levels on productivity, Zn homeostasis, and health status in growing pigs fed a grain and soybean meal-based diet with a high inclusion of phytase (1000 phytase units). Ninety pigs were offered a diet with 1431 and 83 ppm total Zn from weeks 0–2 and 2–6 post-weaning, respectively, followed by one of three dietary Zn levels (31 (unsupplemented), 69, or 102 ppm total Zn, n = 30/Zn level) from weeks 6–16 post-weaning (30–110 kg). Productivity and health were unaffected by dietary Zn level. Despite differences in serum Zn according to dietary Zn level in week 10, serum Zn remained above the assumed sufficient level following all dietary Zn levels through the experiment. No signs of parakeratosis were observed, and we conclude that growing–finishing pigs produce and stay healthy without added Zn to a phytase supplemented grain–soybean meal-based diet when optimal dietary Zn levels are applied up to 30 kg.

The study examined the effects of a microencapsulated complex of biofactors and antioxidants (P(BF + AOx)) on growth and health status of broiler chickens challenged with cold stress. Day-old broilers were allotted to four treatments in a 2 × 2 factorial design with two dietary treatments: (1) Control (CON; corn–wheat–soybean-based) and (2) CON + 0.015% P(BF + AOx), and two thermal treatments: (1) Thermoneutral (TN; 29 °C ± 1 on days 8–10, 54 h) and (2) Cold stress (CS; 20 °C on days 8–10, 54 h). Treatments were allocated to six replicates, with eight chicks/replicate. Growth performance was measured weekly from days 0–21. On day 14, two birds/cage were euthanized. Cold stress reduced (P < 0.05) total antioxidant capacity (TAC), serum IgM, jejunal villus height (VH), villus width (VW), and VH:crypt depth (VH:CD). Irrespective of CS, P(BF + AOx) improved (P < 0.05) feed intake (631 vs. 592 g/bird), body weight (BW) (383 vs. 349 g/bird), BW gain (337 vs. 301 g/bird) up to day 14, and plasma TAC. Regardless of the challenge model, P(BF + AOx) increased (P < 0.05) duodenal VW, VH:CD, jejunal, and ileal VH:CD, and the relative abundance of cecal Intestinimonas and Colidextribacteria, compared to the CON. In conclusion, CS altered broiler blood parameters and gut morphology, but 0.015% P(BF + AOx) improved early life growth performance, TAC, and gut health, irrespective of CS, suggesting that it could be an effective strategy to support overall health and performance.

A total of 1488 pigs were transported to slaughter using a mechanically ventilated vehicle in the winter in Canada. On each of six journeys, a sub-sample of 78 pigs were randomly assigned to two space allowances (0.46 or 0.53 m²/pig), distributed across six compartments, in two positions (near-front and near-rear) and three deck levels (top, middle, and bottom). Compartment ambient conditions (e.g., T °C and RH %) were monitored during transport, and pig behaviour was recorded during lairage. Blood lactate, hematocrit, creatine kinase (CK) concentrations, and meat quality in the longissimus (LM), semimembranosus (SM), and adductor (AD) muscles were assessed on a total of 108 pigs. Pigs transported at 0.53 m²/pig had greater blood hematocrit levels (P = 0.05), but lower blood CK concentrations at slaughter (P = 0.01). The top deck was colder during all transport events (P < 0.001), and pigs transported in this location stood less in lairage compared to those transported on the bottom deck (P = 0.05). Pigs from the top deck showed lower lightness (L^*) values in the LM and SM muscles (P = 0.02 and 0.04, respectively). Overall, animal location had a greater impact than space allowance on animal welfare and meat quality of pigs.

This study aimed at assessing the effects of space allowance on microclimate and pig stress during transportation in a mechanically-ventilated vehicle. On each journey (6), 114 pigs were randomly assigned to different space allowances (0.46, 0.49, or 0.59 m²/pig) tested in the near-front, middle, and near-rear compartments and on the top, middle, and bottom decks. In each compartment, ambient conditions (e.g., T °C and RH %) were monitored. Behaviour was recorded during lairage. A total of 162 pigs were selected for the analysis of blood hematocrit proportion and lactate, and creatine kinase (CK) concentrations, and the evaluation of meat quality in the loin and ham muscles. The bottom deck was more humid before and during transport (P ≤ 0.05) and pigs from this location stood and drank more in lairage (P < 0.001). Pigs transported on the top deck had greater blood lactate and CK concentrations (P < 0.05) than those transported on the bottom deck, and when transported at 0.49 m²/pig produced paler loins (P < 0.05) than those transported at 0.46 m²/pig. The within-trailer location had a greater impact on the microclimate, collected animal welfare measures, and meat quality of pigs transported in an actively ventilated trailer than space allowance.

This study evaluated the effects of corncob as a source of insoluble fibre and xylanase enzyme on broiler chicken performance, ileal digestibility, intestinal morphology, gastrointestinal pH, and serum biochemical traits. Two hundred fifty six 1-day-old (Ross 308) broiler chicks were randomly given six diets for 24 days: a control diet with 0%, 2.5%, or 5% corncob, with or without xylanase, in a 3 × 2 factorial arrangement. Then, chicks were given the control diet with or without xylanase until they reached 42 days. Adding corncob to diets reduced performance during the grower phase (P ≤ 0.05), but when removed, the performance did not differ from the control (P ≥ 0.05). Corncob reduced ash digestibility and cholesterol levels (P ≤ 0.05) while increasing the relative weight of the heart, gizzard, and duodenum and improving the ileal villus high-to-crypt depth ratio (P ≤ 0.05). The feed conversion ratio increased due to corncob inclusion in diets at the starter and grower phases (P ≤ 0.05) but did not differ from the control at the finisher phase. Xylanase supplementation improved performance, nutrient digestibility, intestinal histomorphology, and reduced cecum weight with digestive tract pH (P ≤ 0.05). Therefore, adding corncob with xylanase enzyme to broiler chickens’ diet does not negatively impact their performance. On the contrary, it improves the broilers’ health and reduces production costs.

Displaced abomasum (DA) is an important digestive condition that adversely affects the economic performance and the productive lifespan of a dairy cow. Due to increasing DA incidence in recent years, the present research was performed to estimate the potential effects of DA on the performance of Iranian Holstein. Production data were analyzed using a linear mixed model. Cox proportional hazard regression was used to assess the associations of DA occurrence with the time from calving to first service, pregnancy (in 120 and 220 DIM, respectively) and culling. The least-square means showed that DA was significantly (P < 0.0001) associated with reduced milk, fat, and protein yields, especially during peak milk production. Results of survival analyzes showed that DA could be associated with reduced probability pregnancy in the first service at 120 DIM (hazard ratio = 0.57; 95% CI = 0.51–0.64), and at 220 DIM (hazard ratio = 0.81; 95% CI = 0.76–0.86) and with an increased hazard of culling in the same lactation (hazard ratio = 3.85; 95% CI = 3.13–4.74). Considering negative effects of DA in dairy cows, it can be concluded, quantitative knowledge of the consequences of DA may convince dairy farmers to apply preventive strategies to reduce the incidence of DA in the herd.

Ulcerative colitis is a chronic idiopathic inflammatory bowel disease (IBD) that seriously impacts human health. So far, little information has been reported on the possible benefits of polysaccharides from Scutellaria baicalensis Georgi (SBGP) in alleviating colitis. Therefore, our study investigated the potential therapeutic effects of SBGP on mice with DSS-induced colitis. Results showed that SBGP administration ameliorated the severity of clinical symptoms and enhanced immunomodulatory effects in dextran sulfate sodium (DSS)-treated mice. Additionally, SBGP was found to regulate the inflammatory response, improve mucosal barrier integrity, and maintain tight junctions in the colonic epithelium. Furthermore, SBGP was found to restrain the activation of Notch and MLCK/MLC signaling pathways, which play important roles in inflammation and epithelial barrier homeostasis. These findings suggest that SBGP may have therapeutic potential for the treatment of colitis and other IBD.

Relationships between farm and animal factors and the fatty acid (FA) profile and milk amyloid A (MAA) content of milk were determined in 336 Holstein dairy cows on 24 Quebec farms using multiple regression. Cows with a somatic cell count (SCC) >200 000, and farms feeding palm oil were excluded. Independent factors of the regression models included days in milk (DIM), parity, yield, fat and protein contents of milk, SCC, and the dietary contents of neutral detergent fiber (NDF) and crude fat (CFAT). Nonsignificant variables with P > 0.25 were stepwise removed. Models with high fits were those of total short-chain FA, medium-chain FA, odd- and branched-chain FA (OBCFA), and saturated long-chain FA with R² of 0.33, 0.36, 0.34, and 0.41, respectively. The fat and protein contents and yield of milk did not affect the milk FA profile. Higher NDF increased the milk fat proportions of short-chain FA and OBCFA and decreased those of monounsaturated (MUFA) and polyunsaturated FA (PUFA). Higher CFAT reduced this proportion of short-chain FA but increased those of MUFA and PUFA. Increasing DIM reduced this proportion of short-chain FA and increased that of medium-chain FA. Higher SCC increased MAA.

The objective was to measure the effect of temperature–humidity index (THI) on egg-laying and hatching parameters. Quails were randomly transferred to two cage blocks at 20.55 ± 0.05 °C and 52.25 ± 0.68% relative humidity (RH), accepted as 66 THI group. One cage block was transferred to the next room at 16.15 ± 0.13 °C and 70.77 ± 0.38% RH considered as 61 THI group. In the second stage of the study, the cage block previously accepted as 61 THI group was considered as to 69 THI group by rising up the temperature to 21.97 ± 0.18 °C. The group previously considered as 66 THI group was accepted as 76 THI group by rising up the temperature to 28.06 ± 0.02 °C. Feed consumption and egg weight were significantly decreased, in 69 and 76 THI groups. Daily egg production was lower in 61 and 66 THI groups than that in 69 THI group. In 76 THI group, shell weight and yolk height were decreased. High THI caused negative effects on feed consumption, egg weight, egg quality, and feed conversion ratio.

Eight ruminally cannulated Angus cross heifers (518 ± 33.4 kg) were used in a replicated 4 × 4 Latin square to examine the impact of a sugarcane polyphenol extract (SPE) on feed intake, rumen fermentation, apparent total tract digestibility, methane (CH₄) production, and the rumen microbiome. Heifers were offered a corn silage-based diet with either 0%, 0.3%, 0.6%, or 1.2% of SPE replacing barley grain. Rumen fluid was analysed for volatile fatty acids, protozoa counts, and bacterial diversity. Rumen pH data loggers were used for continuous measurement of ruminal pH and heifers were housed individually to measure apparent total tract digestibility. Cattle were placed into respiration chambers to measure CH₄ production. Data were analysed using the mixed model procedure of SAS with the fixed effect of treatment, and the random effects of block, heifer nested within block, and period. Supplementation of SPE increased absolute ruminal pH (P ≤ 0.01) and its variability (P = 0.05); however, there was no impact on intake, rumen fermentation or bacterial diversity (P ≥ 0.11). The results of this study suggest that SPE does not influence CH₄ production in heifers fed high-forage diets.

This study measured the digestibility of crude protein, crude fat, and dry matter in three protein sources: poultry by-product meal (PBPM), poultry viscera, and crushed mealworms using diatomaceous earth as an indicator. A control diet was made, and test diets were mixed in a 70:30 control diet:test ingredient ratio. Forty-four female mink housed in individual cages were fed experimental diets for 5 days, and fecal samples were collected and analyzed for nutrient residues compared to the diet composition to determine digestible nutrient levels. Mealworms had a greater dry matter digestibility (P < 0.01; 96.26%) than poultry viscera (77.29%) and PBPM (86.76%). PBPM had a lower fat digestibility (P < 0.01; 84.64%) than mealworms (94.78%) and poultry viscera (98.15%). There was no significant difference among treatments for protein digestibility. Using a standard nitrogen-to-protein conversion factor of 6.25, the crude protein content of the mealworms was 51.74%, although with an apparent digestibility coefficient of 0.77, this ingredient had an available crude protein composition of 39.70 ± 2.95. A nitrogen-to-protein conversion factor of 4.80 would be more accurate than 6.25 when using mealworms as a feed ingredient for monogastric animals.

Antimicrobial use and misuse in the agricultural sector are driving causes of the ongoing antimicrobial resistance public health crisis. To enact meaningful on-farm stewardship and best-practice discussions, we need more research that provides in-depth understandings of producers’ beliefs, values, practices, and challenges surrounding the use of antimicrobials. Through a discussion of the experiences of twelve cow–calf operators in Ontario, we demonstrate how qualitative research methods can be mobilized to gain insights into the priorities and concerns that shape farmers’ use of antimicrobials, as well as barriers to their effective use.

The objective of this study was to determine the effect of time of feeding pre-farrow on farrowing time and duration. Two hundred and ninety-eight mixed parity sows were assigned to morning (0700 h) or evening (1900 h) feeding upon entry into the farrowing room until farrowing. More sows from the morning-fed group farrowed between 0700 and 1500 h than the evening-fed group (51.43 vs. 21.95%, P < 0.001). There were no differences (P > 0.10) in farrowing duration. Number of piglets born alive, stillborn, and mummies did not differ (P > 0.10) among treatments. Evening-fed sows had an increased number of pigs weaned, resulting from reduced preweaning mortality compared to the morning-fed sows (P < 0.05). Morning feeding may be beneficial for maximizing the number of farrowing events that start during working hours and evening feeding may improve litter outcomes.