Search

A total of 91 sows (Line 241, DNA Genetics) were used to evaluate the effects of supplemental fat sources and essential fatty acid intake on sow farrowing performance, litter growth performance, and essential fatty acid composition of colostrum, milk, and adipose tissue. At approximatelyday 107 of gestation, sows were blocked by body weight and parity, then allotted to 1 of 5 experimental treatments as part of a 2 × 2 + 1 factorial arrangement. Experimental diets were corn-soybean meal-based with a control diet that contained no added fat or diets with 3% added fat as either beef tallow or soybean oil, with consumption of the added fat diets starting on day 107 or 112 of gestation and fed until weaning. Thus, sows were provided low essential fatty acids (EFA; as linoleic and α-linolenic acid) without supplemental fat or with beef tallow or high EFA with soybean oil. Sows were provided approximately 2.8 kg/d of their assigned lactation diet pre-farrow and then provided ad libitum access after parturition. Sows consuming diets with beef tallow had greater lactation ADFI (fat source, P  = 0.030), but lower daily linoleic acid (LA) and α-linolenic acid (ALA) intake than sows that consumed diets with soybean oil (fat source, P  < 0.001). Supplemental fat sources providing either low or high EFA did not influence litter growth performance (fat source, P  > 0.05). Sows fed diets with beef tallow did not influence the LA composition of colostrum; however, lactation diets with high EFA provided by soybean oil on day 107 of gestation increased colostrum LA concentration compared to providing diets on day 112 of gestation (fat source × time, P  = 0.084; time, P  < 0.001). Additionally, regardless of pre-farrow timing, ALA concentration of colostrum increased when sows consumed diets with soybean oil compared to beef tallow (fat source, P  < 0.001). Both LA and ALA concentrations of milk at weaning were greater for sows that consumed diets with soybean oil compared to beef tallow (fat source, P  < 0.001). Furthermore, concentrations of LA and ALA within adipose tissue were greater at weaning when sows consumed diets with high EFA compared to low EFA (fat source, P  < 0.05). These responses suggest that providing dietary fat sources with high concentrations of EFA can increase backfat, colostrum, and milk LA and ALA. However, in this experiment, changes in colostrum and milk composition did not influence litter growth performance. [ABSTRACT FROM AUTHOR]

Three experiments were conducted to determine the effects of increasing soybean meal (SBM) levels by replacing feed-grade amino acids (AA) in corn, corn dried distillers grains with solubles (DDGS), and corn-wheat midds-based diets on growth performance of late finishing pigs (n = 4,406) raised in commercial facilities. Across all experiments, pens of pigs were blocked by initial bodyweight (BW) and randomly assigned to 1 of 5 dietary treatments. All diets were formulated to contain 0.70% standardized ileal digestible (SID) Lys and varying amounts of feed-grade AA. All diets were formulated to meet or exceed minimum essential AA requirement estimates as a ratio to Lys. In Exp. 1, 1,793 pigs (initially 104.9 ± 4.9 kg) were fed corn-based diets and pens of pigs were assigned treatments with increasing SBM from 5% to 20%. Overall, average daily gain (ADG) and feed efficiency (G:F) improved (linear and cubic, P ≤ 0.02) as dietary SBM increased, with the greatest improvement observed as SBM increased from 5% to 8.75% and little improvement thereafter. In Exp. 2, 1,827 pigs (initially 97.9 ± 4.3 kg) were fed diets containing 25% DDGS with SBM levels increasing from 0% to 16%. Overall, feed efficiency marginally improved (linear, P ≤ 0.10) as SBM increased, with the greatest performance observed when diets contained 8% SBM and similar performance thereafter with 12 or 16% dietary SBM. In Exp. 3, 786 pigs (initially 96.7 ± 3.2 kg) were fed diets that contained 30% wheat midds and dietary SBM from 0% to 16%. Final BW of pigs increased (linear, P < 0.05) and overall ADG and G:F improved (linear and cubic, P < 0.05) as SBM increased. The combined results of the three experiments suggest that inclusion of at least 4% to 8% dietary SBM at the expense of feed-grade amino acids in corn-based diets with or without grain coproducts can improve growth performance of late-finishing (greater than 100 kg) pigs. [ABSTRACT FROM AUTHOR]

Branched-chain amino acids (BCAA) are three essential amino acids (AA) for lactating sows; however, the effects of dietary Leu, Val, and Ile on sow and litter performance within the literature are equivocal. The BCAA are structurally similar and share the first steps of their catabolism pathway where Leu, Val, and Ile are transaminated through BCAA aminotransferase and irreversibly decarboxylated by the branched-chain α-ketoacid dehydrogenase complex. Although these steps are shared among BCAA, Leu is recognized as the primary stimulator due to Leu's greater affinity towards the enzymes compared to Val and Ile. Since the late 1990s, sows are producing larger and heavier litters and generally consume diets with greater concentrations of Leu and crystalline AA, which may create imbalances among dietary BCAA. Research conducted with growing-finishing pigs confirms that high concentrations of Leu can impair BCAA utilization and growth performance. However, the effects of BCAA on lactating sow and litter performance are not as clearly understood. Within mammary tissue, BCAA uptake is greater than milk output of BCAA since Val, Ile, and Leu are catabolized to form non-essential AA, lactose, fatty acids, and other metabolites. Within the mammary gland, BCAA aminotransferase activity is much higher than within skeletal muscle, liver, or small intestine. Thus, competition among the BCAA, namely, between Leu and Val, can significantly inhibit Val uptake within mammary tissue. Therefore, dietary modifications that mitigate BCAA competition may positively influence Val utilization for colostrum and milk synthesis. Little data exist on Ile and Leu requirements for modern lactating sows. Although Val requirements have been extensively researched in the last 25 yr, an ideal Val:Lys has not been consistently established across experiments. Some studies concluded that total Val concentrations above 120% of Lys optimized performance, whereas others determined that increasing SID Val:Lys from 55% to 136% did not improve piglet growth performance. Although increasing dietary Val positively influences fat and protein composition of colostrum and milk, litter growth during lactation is not always positively affected. Given the competition among BCAA for utilization within mammary tissue, research evaluating the Leu and Ile requirement of modern lactating sows is warranted to fully understand the influence and interactions of BCAA on reproductive and litter growth performance. [ABSTRACT FROM AUTHOR]

Two studies were conducted to estimate the SID Thr:Lys requirement for growth and feed efficiency of PIC 337×1050 pigs from approximately 12- to 70-kg. In Exp. 1, 987 pigs [initial body weight (BW) = 11.8±0.32 kg] were used from 12- to 24-kg. In Exp. 2,875 pigs (initial BW = 43.4±0.58 kg] were used from 43- to 70-kg. Pens of pigs were blocked by BW and randomly allotted to dietary treatments in randomized complete block designs, with 21 to 27 pigs per pen with 8 and 7 replications per treatment (Exp. 1 and 2, respectively). Pens were provided 1 of 5 dietary treatments with increasing SID Thr:Lys ratios at 53, 58, 62, 65, and 68% in each experiment. Two corn-soybean meal-based diets containing 53 and 68% Thr:Lys ratios were blended to achieve target SID Thr:Lys treatment levels in each experiment. In Exp. 1 (12- to 24-kg), ADG and final BW increased (linear, P = 0.006) while ADFI, G:F, Thr intake/d, and Thr intake/kg of gain increased (quadratic, P = 0.001) as Thr:Lys ratio increased (Table). Additionally, Lys intake/d increased (quadratic, P < 0.001) while Lys intake/kg of gain decreased (quadratic, P < 0.001) with increasing Thr:Lys ratio. In Exp. 2 (43- to 70-kg), ADG, G:F, final BW, Thr intake/d and Thr intake/kg of gain also increased (linear, P = 0.036) as dietary Thr:Lys increased. Moreover, Lys intake/kg of gain decreased (linear, P = 0.023) with increasing Thr:Lys. A quadratic polynomial (QP) model predicted a requirement at levels greater than 68% SID Thr:Lys for ADG from 12- to 24-kg, while a QP model suggested that maximum G:F was achieved at 61.8% SID Thr:Lys (Exp. 1). From 43- to 70-kg, QP models suggested maximum ADG and G:F were achieved at levels greater than 68% SID Thr:Lys (Exp. 2). However, similar fitting BLL models predicted no further improvement to G:F and ADG beyond 65 and 67% SID Thr:Lys, respectively. In summary, these results suggest the optimal SID Thr:Lys for 12- to 24-kg pigs is 61.8% for feed efficiency and greater than 68% for ADG. From 43- to 70-kg, the requirement was predicted at or above 65 and 67% SID Thr:Lys for G:F and ADG, respectively. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate growth performance and economic return of PIC 800 × Camborough pigs fed increasing SID Lys from approximately 12- to 136-kg. Pens of pigs were blocked by body weight (BW) and randomly assigned to 1 of 5 dietary treatments in a randomized complete block design with 26 pigs per pen and 16 pens per treatment. Pens were provided 1 of 5 dietary treatments with increasing SID Lys at 85, 93, 100, 107, and 115% of current (2021) PIC recommendations within 6 dietary phases as follows: phase 1 (1.09, 1.19, 1.28, 1.36, and 1.47%), phase 2 (0.97, 1.06, 1.14, 1.22, and 1.32%), phase 3 (0.87, 0.95, 1.02, 1.09, and 1.17%), phase 4 (0.75, 0.82, 0.88, 0.94, and 1.01%), phase 5 (0.66, 0.72, 0.77, 0.82, and 0.89%), and phase 6 (0.59, 0.64, 0.69, 0.74, and 0.79%). Two corn-soybean meal-based diets containing low and high Lys were blended to achieve target SID Lys levels for each treatment diet within phase. Overall (d 0 to 143), increasing SID Lys improved (linear, P = 0.007) ADG and G:F, but did not impact ADFI (P > 0.10; Table). A tendency (linear, P = 0.067) for heavier hot carcass weights (HCW) was observed in pigs fed increasing SID Lys. However, there was no evidence for differences (P > 0.10) in carcass yield, backfat depth, loin depth, or carcass lean percentage across treatments. The linear (LM) model served as the best fit for both growth and economic parameters. The LM model predicted maximum ADG and G:F at levels greater than 115% of PIC's current recommendations. However, for income over feed cost (IOFC), the LM model predicted maximum profitability at or below 85% of the current Lys recommendations of PIC. In conclusion, the optimal SID Lys level for PIC 800 × Camborough pigs from 12- to 136-kg differed upon response criteria, with growth performance maximized at levels at or above 115% of the recommendation for SID Lys by PIC; however, maximal economic returns were observed at or below 85% of PIC's current SID Lys recommendations. [ABSTRACT FROM AUTHOR]

The objective of the first experiment was to determine the effects of corn particle size on the diet apparent total tract digestibility (ATTD) of protein (CP), digestible energy (DE), metabolizable energy (ME) and N-corrected ME (AMEn) in addition to estimating the ME of corn in gestating sows. A total of 27 sows, during the second phase of gestation, were fed a common diet manufactured with corn ground to one of 3 target particle sizes (dgw): 400, 800, or 1200 μm. Titanium dioxide (0.25%) was included in the diet as an indigestible marker for digestibility calculations. Sows were fed experimental diets for 7 days to allow for diet adaptation before a 2-day collection period of urine and fecal samples. Reducing dgw of corn from 1,200 to 400 μm increased (linear, P < 0.01) ATTD CP and GE, DE, ME, AMEn and calculated ME of corn. The objective of the second experiment was to determine the effects of corn particle size on the total concentration and molar proportions of volatile fatty acids (VFA) in the feces of gestating sows. A total of 27 sows were fed treatments similar to Exp. 1 from day 61 to 82 of gestation. On day-82 and 83 of gestation, 2 fecal grab samples were collected for VFA analyses. Sows fed diets with decreasing corn dgw had increased (quadratic, P = 0.021) fecal acetic acid proportions, and decreased propionic (quadratic, P = 0.019) and valeric acid (P = 0.005). In conclusion, for every 100 μm decrease in corn dgw from 1,200 to 400 μm, corn ME value increased by 28.6 kcal/kg. Additionally, decreasing corn particle size led to an increase in the proportion of acetic acid and a decrease in propionic and valeric acid in fecal samples of gestating sows. [ABSTRACT FROM AUTHOR]

Two experiments were conducted to determine the effects of increasing levels of soybean meal (SBM) replacing feed grade amino acids in corn or corn-dried distillers grains with solubles (DDGS)-based diets on growth performance of late finishing pigs. In both experiments, there were 22 to 27 pigs per pen and 14 pens per treatment. Average length of the experiments was 35 (Exp. 1) and 29 days (Exp. 2). Diets were balanced to contain 0.70% SID Lys and 2,667 or 2,610 kcal NE/kg for Exp. 1 and 2, respectively. Minimum amino acid ratios relative to Lys were: Ile, 55; Met&Cys, 60; Thr, 65; Trp, 19.5, and Val, 70. Dietary crude protein ranged from 10.1 to 15.2 for Exp. 1 and 13.6 to 19.4 for Exp. 2. The statistical model considered fixed effects of treatment, linear and quadratic contrasts, and random effect of block. In Exp.1, 1,793 pigs (L337×1050, PIC; initially 104.9 ± 1.4 kg) were fed corn-based diets and pens of pigs were assigned to 1 of 5 dietary treatments with increasing SBM from 5 to 20%. Overall, average daily gain (ADG) and gain-to-feed (G:F) increased (linear; P < 0.05) as SBM increased with the greatest improvement observed as SBM increased from 5 to 8.75%, with little improvement thereafter. In Exp. 2, 1,827 pigs (L337×1050, PIC; initially 97.9 ± 1.1 kg) were used in a similar study as Exp. 1, but all diets contained 25% DDGS and SBM levels increased from 0 to 16%. Overall, G:F and final bodyweight of pigs marginally improved (linear and quadratic, respectively; P < 0.10) as SBM increased, with the greatest performance observed when diets contained 8% SBM. These results suggest that increasing SBM up to 8% at the expense of feed grade amino acids in corn or corn-DDGS-based diets improved ADG or G:F in late-finishing pigs. [ABSTRACT FROM AUTHOR]

The objective of this experiment was to determine pre-weaning survival of pigs when sows were supplemented with 3 dietary levels of Zn in late gestation. Gilts and sows (n = 339) were assigned to one of three dietary treatments based on parity. Treatments were: 1) Control - corn-soybean meal-based diet containing 125 ppm supplemental Zn as ZnSO4 (75 ppm Zn) and AvailaZn™ (50 ppm Zn, CON); 2) Intermediate - as Control + 240 ppm supplemental Zn as ZnSO4 (INT); and 3) High - as Control + 470 ppm supplemental Zn as ZnSO4 (HI). Final supplemental Zn concentrations of diets were: 1) CON - 125 ppm; 2) INT - 365 ppm; and 3) HI - 595 ppm. Sows received dietary treatments from about d 85 of gestation until farrowing. Individual piglet birth weights were recorded within 12 h of parturition and all instances of piglet mortality were recorded. The statistical model considered fixed effects of diet and random effects of parity. Chi-square analysis was used to determine diet effects on piglet mortality. There were no differences in total pigs born, born alive, or weaned per litter. However, piglets from sows fed the INT diet had heavier (P < 0.05) birth weights (1.42 kg) than those fed CON (1.38 kg). Furthermore, incidence of low birth weight pigs was less (P < 0.05) for sows consuming INT compared with sows fed CON and HI (Table 1). Overall piglet mortality tended to decrease (P < 0.10) as dietary Zn increased. Furthermore, mortality of low birth weight pigs decreased (P < 0.05) as dietary Zn increased. Overall, effects of supplemental dietary Zn at 365 and 595 ppm in late gestation improved pre-weaning survival of low birth weight piglets and reduced overall pre-weaning mortality of piglets. [ABSTRACT FROM AUTHOR]