Journal of Animal Science

Stansberry, McKeeley C; Ogundare, Wonders; Beckett, Linda M; Garcia Reis, Leriana; Tobolski, Evy M; Anele, Uchenna; Richert, Brian T; Schinckel, Allan P; Casey, Theresa M; Minor, Radiah C

doi: 10.1093/jas/skae356pmid: 39704296

Lactating sows and their litters are particularly vulnerable to heat stress (HS). HS decreases fertility, feed intake, milk production, and litter growth of sows. Approaches are needed to mitigate the negative effects of HS on animal welfare and oxidative damage to tissues. The objective of this study was to measure the efficacy of conductive heat removal using electronic cooling pads (ECP) and feeding Moringa oleifera (4% of the diet, M), a feedstuff high in antioxidants, to sows from late gestation to weaning on their welfare and production performance. A study was conducted using a 2 × 2 factorial design of treatments, with mixed parity Yorkshire × Landrace sows (n = 48). The sows were exposed to moderate HS conditions from gestation day 110 to day 21 of lactation. To achieve moderate HS, the farrowing room temperature was increased incrementally daily from 25 °C to 32 °C between 0800 and 1100 hours and decreased from 32 °C to 26 °C between 1700 and 2000 hours. Sows were limit fed during gestation (1.36 kg 2X/d) and fed ad libitum post farrowing. Treatments included HS + control corn–soybean meal (CS)-based diet (HS + CS), HS + M, ECP + CS, ECP + M (n = 12/treatment). Sow respiration rate (RR) and rectal temperature (RT) were measured four times daily (0600, 1300, 1600, and 1900 hours). The use of ECP decreased lactating sow RR (HS = 66.6 bpm, ECP = 28.3 bpm, P < 0.0001), RT (HS = 39.2 °C, ECP = 38.8 °C, P = 0.003), and lactation body weight (BW) loss (HS = −21.67 kg, ECP = −5.1 kg P = 0.002). ECP by time-of-day interactions (P < 0.01) existed for RR and RT, with ECP having a greater impact from 1300 to 1900 hours, than at 0600 hours. ECP increased the intake of lactation feed (P = 0.02). An ECP by diet interaction (P = 0.0004) indicated that ECP increased the intake of lactation feed for the sows fed the CS diet (6.48 vs. 4.42 kg/d, P = 0.0004), but did not affect the feed intake of sows fed the M diet. The treatment did not affect litter weaning weight (P = 0.14). Moringa increased percent fat in milk (M = 12.28%, CS = 11.06%, P = 0.05). The reduction in sow RR and RT, and increase in feed intake with lower loss of BW indicate that ECP improved sow well-being in the HS environment. Neither ECP nor M affected litter growth, despite M increasing fat content of milk and ECP–CS increasing feed intake.

Dobbins, Thomas W; Swanson, Rebecca M; Dennis, Amberly A; Rivera, J Daniel; Dinh, Thu T N; Lemley, Caleb O; Burnett, Derris D

doi: 10.1093/jas/skae377pmid: 39679952

The neuroendocrine hormone melatonin is associated with circadian rhythms and has antioxidant and vasodilative properties. In cattle, melatonin rescues fetal growth during maternal nutrient restriction in a seasonally dependent manner, but melatonin research in swine is limited. The objective of this study was to evaluate the effects of dietary melatonin supplementation during mid to late gestation on circadian rhythm and muscle growth and development of the longissimus dorsi in utero and postnatally. Sows received 20 mg of dietary melatonin daily (MEL) or no melatonin supplement (CON). Experiment 1 supplemented sows from gestational age (dGA) 38 ± 1 to 99 ± 1, experiment 2 supplemented sows from 41 to 106 ± 1 dGA, and experiment 3 supplemented sows from 60 dGA to farrowing. At harvest, morphometric measurements of all fetuses were taken, while the small (SM), medium (MED), and large (LG) piglets from each litter were used for further analysis. Prenatal data were analyzed using the MIXED procedure of SAS, and postnatal data were analyzed using the GLIMMIX procedure. Fetal morphometrics were analyzed for fixed the effect of treatment, and transcript abundance was analyzed for treatment, time, and size. Postnatal parameters were analyzed for fixed effects of treatment, size, and production stage. In experiment 1, MEL increased (P = 0.016) Period 1 (PER1) transcript abundance in the evening (PM) compared to the morning (AM). In experiment 1, myogenin (MYOG) transcript abundance was increased (P = 0.033) in MEL fetuses in the AM compared to MEL in the PM. Myogenic factor 5 (MYF5) and paired box 7 (PAX7) were increased (P = 0.016) in the PM. Fetuses from MEL-treated sows had increased (P < 0.05) BW, curve crown-rump length, and head circumference in experiment 2. In experiment 2, MEL increased (P = 0.012) PER1 and Period 2 (PER2) transcript abundance in the PM. In experiment 2, myoblast differentiation 1 (MYOD) was increased (P = 0.016) in SM and MED fetuses, while MYF5 and PAX7 were increased (P = 0.019) in SM fetuses. Postnatal BW was increased (P = 0.025) in MED and LG MEL-treated offspring compared to CON. Insulin-like growth factor 1 (IGF1) was downregulated (P = 0.050) in MEL-treated offspring, while insulin-like growth factor 1 receptor (IGF1R) was upregulated (P = 0.009) in MEL offspring. These results indicate that maternal melatonin supplementation during gestation modulates fetal circadian regulatory genes and alters myogenic genes during growth.

Messersmith, Elizabeth M; Hansen, Stephanie L

doi: 10.1093/jas/skae365pmid: 39673410

The effects of supplemental Zn within steroidal implant strategy on performance, carcass characteristics, trace mineral status, and muscle gene expression were tested in a 59-d study using 128 Angus-crossbred steers (492 ± 29 kg) in a 2 × 4 complete randomized design. Implant strategies included no implant (NoIMP) or Component TE-200 (TE200; Elanco, Greenfield, IN) administered on day 0. Zinc was supplemented at 0, 30, 100, or 150 mg Zn/kg dry matter (Zn0, Zn30, Zn100, Zn150, respectively) from ZnSO4. Steers were stratified by body weight (BW) to pens (n = 5 or 6 steers/pen) equipped with GrowSafe bunks (GrowSafe Systems Ltd., Airdrie, AB, Canada) and assigned treatments (n = 15, 16, or 17 steers/treatment). Cattle were weighed on days −1, 0, 18, and 59 with blood collected on days −1, 18, 40, and 59. Muscle samples were collected from the longissimus thoracis on day 11 and liver samples were collected on day 55 or 56. Data were analyzed using the Mixed Procedure of SAS via contrast statements testing the linear and quadratic response to Zn supplementation within implant treatment and NoIMP vs. TE200 for performance, carcass, blood, and liver parameters. Specific contrast statements were formed for the analysis of gene expression in muscle including: Zn0 vs. Zn150 within NoIMP and TE200, NoIMP vs. TE200 (Zn0 and Zn150 only), and the linear effect of supplementing Zn0, Zn100, and Zn150 within TE200. Steer was the experimental unit. Day 18 BW and days 0 to 18 average daily gain (ADG) were linearly increased due to Zn supplementation within TE200 (P ≤ 0.002) in conjunction with a linear increase from Zn in day 11 muscle epidermal growth factor receptor, matrix metalloproteinase 2, and phosphodiesterase 4B gene expression of TE200 steers (P ≤ 0.05). Plasma Zn on days 18 and 40 linearly increased with increasing Zn supplementation regardless of implant treatment (P ≤ 0.03) and was lesser for TE200 than NoIMP steers on day 18 (P = 0.001). Day 59 BW and hot carcass weight (HCW) were greater for TE200 vs. NoIMP (P ≤ 0.002) and HCW of implanted steers tended to linearly increase with increasing Zn supplementation (P = 0.09). No effects of Zn supplementation were observed in NoIMP for HCW, BW, or ADG (P ≥ 0.17). Yield grade and 12th rib fat tended to quadratically decrease within NoIMP (P ≤ 0.09), with Zn100 being the most lean. These data indicate increasing supplemental Zn influences steroidal implant signaling machinery while increasing the Zn status and implant-induced growth of feedlot cattle.

Peckler, Gretchen L; Fuenzalida, Maria Jose; Aulik, Nicole; Adcock, Sarah J J

doi: 10.1093/jas/skae375pmid: 39659242

Subclinical mastitis, the asymptomatic inflammation of the udder often caused by bacterial infection, is an important economic and welfare concern in meat-producing flocks. We conducted a longitudinal observational study to: (1) characterize the etiology, prevalence, incidence, and persistence of intramammary infections during the first 8 wk of lactation, and (2) investigate the potential risk factors of lactation stage, parity, and the number of lambs reared. Duplicate milk samples (n = 592) were collected aseptically from each udder half of 37 clinically healthy ewes (9 Hampshire, 22 Polypay, and 6 Targhee) weekly for their first 8 wk of lactation. A sample was considered a true infection if at least 100 CFU/mL of a bacterial species were isolated. Out of a total of 560 non-contaminated duplicate udder half samples, 186 (33.2%) were infected. The prevalence of subclinical mastitis in the first week of lactation was 26.0% at the udder half level and increased over lactation to 47.1% by 8 wk. Over the course of lactation, 34 of the 37 (91.9%) ewes had an intramammary infection in at least one udder half. The most common bacteria isolated were non-aureus Staphylococci (72.1%), Staphylococcus aureus (7.5%), and Mannheimia haemolytica (5.9%). The weekly incidence rate of new infections was 18.0% ± 10.2% (mean ± SD). Infections lasted 2.1 ± 2.1 wk, with 9.0% present the full 8 wk of observation. Spontaneous cures occurred in 36.0% of infection bouts but varied from 0% to 100% depending on the pathogen. The probability of subclinical mastitis infection increased as lactation progressed for ewes rearing single or multiple lambs and for ewes in their first or second parity, but not for ewes in later parities. In conclusion, intramammary infections in this flock were prevalent across lactation, parities, and litter sizes, and varied in their duration and spontaneous cure rate. Improved knowledge of the etiological agents and risk factors involved in subclinical mastitis is important in developing effective control measures in meat-producing flocks.

Musco, Nadia; Pascon, Giulia; Addeo, Nicola Francesco; Zarantoniello, Matteo; Lanzieri, Mariarosaria; Olivotto, Ike; Tulli, Francesca; Iervolino, Valeria; Amato, Ruggero; Lombardi, Pietro; Bovera, Fulvia

doi: 10.1093/jas/skae376

Correa, Federico; Luise, Diana; Virdis, Sara; Negrini, Clara; Polimeni, Barbara; Amarie, Roxana Elena; Serra, Andrea; Biagi, Giacomo; Trevisi, Paolo

doi: 10.1093/jas/skae370pmid: 39657905

Improving the synchrony between amino acids (AAs) and glucose appearance in the blood can support the growth performance of weaned pigs fed a low crude protein (CP) diet. This can be achieved using a diet with a low amylose-to-amylopectin ratio (AM/AP). The aim of this experiment was to evaluate whether reducing the AM/AP by using a corn variety characterized by a high amylopectin content, in the weaning diet can sustain growth performance and improve the intestinal health of pigs fed a low-CP diet. At weaning (25 ± 2 d), 90 pigs were assigned to 3 treatment groups: 1) control group (CTR), fed a standard diet with a medium-high CP content and high AM/AP (days 0 to 13: 18.0% CP, 0.13 AM/AP; days 14 to 27: 16.6% CP, 0.30 AM/AP; days 28 to 49: 16.7% CP, 0.15 AM/AP); 2) a group fed a low-CP diet with a high AM/AP (LP) (days 0 to 13: 16.0% CP, 0.17 AM/AP; days 13 to 27: 14.7% CP, 0.17 AM/AP; days 28 to 49: 14.5% CP, 0.25 AM/AP); 3) a group fed a low CP and a low AM/AP diet (LPLA) (days 0 to 13: 16.0% CP, 0.09 AM/AP; days 14 to 27: 14.7% CP, 0.05 AM/AP; days 28 to 49: 14.5% CP, 0.09 AM/AP). Pigs were weighted weakly until day 49. Fecal samples were collected on days 10 and 42 (12 samples/group/timepoint) for ammonia and calprotectin content and microbiota profile characterization. Until day 28, body weight (BW) of pigs from CTR was not different from pigs of the LPLA group, whereas it was higher from pigs of the LP group (P < 0.05). Thereafter, CTR group had greater BW compared with LP and LPLA groups for all the other timepoints considered (P < 0.05). From days 0 to 7 LPLA group had a lower incidence of diarrhea than the LP group (P = 0.04). On day 10, LPLA group had a greater alpha diversity (Shannon and InvSimpson indices), than the CTR (P = 0.03) and LP (P = 0.04) groups. On day 42, LPLA group had significantly greater InvSimpson diversity than LP group (P = 0.028). On day 10, LP group was characterized by greater abundance of Lactobacillus (LDA score = 5.15, P = 0.02), Clostridium-sensu-stricto-1 (LDA score = 4.90, P = 0.02) and Oscillospiraceae NK4A214-group (LDA score = 4.87, P = 0.004), whereas LPLA group was characterized by greater abundance of Prevotella (LDA score = 5.04, P = 0.003) and Agathobacter (LDA score = 4.77, P = 0.05). In conclusion, while reducing CP levels may negatively impact growth performance, when combined with higher amylopectin levels, it can reduce the incidence of diarrhea and increase fecal microbial diversity.

Catrett, Cassidy C; Moorey, Sarah E; Beever, Jon E; Rowan, Troy N

doi: 10.1093/jas/skae364pmid: 39697106

Reproduction plays a major role in the production efficiency of livestock species. However, cow-centric reproductive traits tend to be lowly heritable and are not expressed until later in an animal’s lifetime, making phenotypic selection alone inefficient at generating genetic gain. Genetic progress can be accelerated by focusing selection on the predicted genetic component of reproductive traits using Expected Progeny Differences. We used the American Simmental Association’s performance and Total Herd Enrollment data, made up of 533,155 calving records from 303,158 females (132,403 cows and 170,755 heifers), 33,732 of which are genotyped, to explore three continuous and two discrete phenotypes focused on quantifying early and sustained fertility in beef cows. We analyzed calving date (CD) (cow’s CD relative to the start of the calving season), calving interval (CI) (days between calves), first calving interval (FCI) (CI observation between the first and second calving record for a female), heifer pregnancy (HP) (did the animal calve as 2-yr-old), and discrete early calving (DEC) (did animal calve in the first 30 d of the calving season) as distinct, but correlated measures of fertility. This dataset provides insight into population-wide trends related to cow attrition, calving season lengths, and phenotypic variation in fertility. We used pedigree and genomic REML to estimate these six phenotypes’ genetic, permanent environment, and temporary environmental variance components. Pedigree-estimated heritabilities were 0.06 (± 0.000011) for CD, (0.04 ± 0.000005) for CI, 0.07 (± 0.000016) for DEC, 0.05 ± 0.000041 for FCI, and 0.23 (± 0.000099) for HP, consistent with other fertility traits across beef and dairy cattle. The incorporation of genomics increased the heritability estimate for HP (0.24 ± 0.000098) and decreased the estimate for FCI (0.04 ± 0.000029). Positive phenotypic and genetic correlations were found among these phenotypes (rG = 0.01 to 0.96). These results call for further work in optimizing genetic predictions and exploration of the genetic architecture through genome-wide studies. Whole herd reporting date frameworks represent opportunities for measuring new reproductive phenotypes, but their utility in genetic evaluations will rely on novel trait initiatives and consistent recording that captures more detailed data.

Gaffield, Katelyn N; Goodband, Robert D; DeRouchey, Joel M; Tokach, Mike D; Woodworth, Jason C; Denny, Gordon; Smolen, Paul; Slipher, Carmen; Krishnan, Hari B; Gebhardt, Jordan T

doi: 10.1093/jas/skae378pmid: 39665847

Depending on the soybean processing plant, gums and soapstocks may be added back to soybean meal during soybean processing. Despite potential effects on soybean meal quality, there is limited information available on the composition and variation in soybean by-products and the resulting soybean meal if by-products are added back during processing. A total of 36 soybean by-product samples from 14 plants across 8 different companies were examined in an industry survey evaluating the composition and variation of soybean gums and soapstocks across the United States. All soybean processing plants in the study produced at least 1 of the 2 by-products: soybean gums or soybean soapstocks. Soybean by-product and soybean meal samples were collected within 2 different timeframes: May to July 2023 and October to November 2023. The individual plants surveyed constitute approximately 30% of total US soybean meal production, with 8 participating companies representing 80% of the total US soybean meal production. By-products were analyzed for lipid quality criteria including moisture, fat by acid hydrolysis, fatty acid analysis, and oxidation markers. Soybean meal samples were submitted for analysis of the proximate composition, neutral detergent fiber, Ca, P, and trypsin inhibitor units. Soybean gums had a greater (P ≤ 0.05) percentage of acid-hydrolyzed fat and p-Anisidine value compared to soybean soapstocks. Soybean soapstocks tended to have a greater (P = 0.085) percentage of moisture and volatile matter as well as an increased (P = 0.052) concentration of insoluble impurities compared with soybean gums. Most notably, there was considerable variation in the composition of by-product samples among processing plants indicating differences in processing procedures or incoming soybean quality. Soybean meal containing added soybean by-products had 61% greater (P < 0.05) ether extract than soybean meal samples without added soybean by-products on a dry matter basis, but there was no difference (P > 0.10) in crude protein. Furthermore, trypsin inhibitor units varied considerably among plants with values ranging from 1.45 to 9.26 TIU/mg of seed powder, regardless of by-product inclusion. These results provide information on the composition and variation in soybean by-products across various processing plants; however, further information is still needed to evaluate their subsequent effects on livestock diets.

Shao, Yuexin; Huang, Jiangtao; Wei, Manhong; Fan, Liaoyu; Shi, Huaiping; Shi, Hengbo

doi: 10.1093/jas/skae352pmid: 39657106

Soybean isoflavone (SIF) in soybeans are natural phytoestrogens, which is functioned as an estrogen agonistic or antagonistic. SIF regulates the capacity of animals to synthesize triacylglycerols by directly utilizing long-chain fatty acids. However, few studies have focused on its regulatory lipid metabolism in lactating dairy goats. The objective of this study was to investigate the influence of SIF on milk yield and composition using Saanen dairy goats as a model, employing both in vivo and in vitro approaches. In the in vivo phase, a total of 20 goats were randomly divided into 2 groups: the control group fed a basal diet, and the experimental group fed a basal diet supplemented with SIF at a dosage of 100 mg/d. The results underscored a significant elevation in serum estrogen and prolactin levels in the SIF-supplemented group (P < 0.05). Notably, SIF supplementation also displayed a higher milk fat percentage (P = 0.03). Transitioning to in vitro experimentation, the addition of SIF (75 µM) to goat mammary epithelial cells exhibited a pronounced effect on cell proliferation. It spurred cell proliferation and led to an increase in triacylglycerol levels (P < 0.05). Consistently, SIF showcased an enhancement in the expression of key genes associated with milk fat de novo synthesis. SIF demonstrated a rescuing effect on the suppressive impact of MK2206 on Akt protein phosphorylation. Importantly, the study observed that the knockdown of estrogen receptor alpha (ERα) expression completely counteracted the effect of SIF on lipid droplet accumulation. Collectively, the current study establishes the critical role of SIF in process of fatty acid de novo in the goat mammary gland. This regulation is notably mediated through the ERα-Akt axis, thus enriching our understanding of this intricate biological process. This research sheds light on the potential benefits of SIF supplementation in dairy goat farming, ultimately contributing to improved milk production and quality.