Search

Diets fed to nonruminant animals are composed mainly of feed ingredients of plant origin. A variety of antinutritional factors such as phytin, nonstarch polysaccharides, and protease inhibitors may be present in these feed ingredients, which could limit nutrients that may be utilized by animals fed such diets. The primary nutrient utilization-limiting effect of phytin arises from the binding of 6 phosphate groups, thus making the P unavailable to the animal. The negative charges allow for formation of insoluble phytin-metal complexes with many divalent cations. Furthermore, phytin and protein can form binary complexes through electrostatic links of its charged phosphate groups with either the free amino group on AA on proteins or via formation of ternary complexes of phytin, Ca2+, and protein. The form and extent of de novo formation of binary and ternary complexes of phytin and protein are likely to be important variables that influence the effectiveness of nutrient hydrolysis in plant-based diets. Nonstarch polysacharides reduce effective energy and nutrient utilization by nonruminant animals because of a lack of the enzymes needed for breaking down the complex cell wall structure that encapsulate other nutrients. Enzymes are used in nonruminant animal production to promote growth and efficiency of nutrient utilization and reduce nutrient excretion. The enzymes used include those that target phytin and nonstarch polysaccharides. Phytase improves growth and enhances P utilization, but positive effects on other nutrients are not always observed. Nonstarch polysaccharide-hydrolyzing enzymes are less consistent in their effects on growth and nutrient utilization, although they show promise and it is imperative to closely match both types and amounts of nonstarch polysaccharides with appropriate enzyme for beneficial effects. When used together with phytase, nonstarch polysaccharide-hydrolyzing enzymes may increase the accessibility of phytase to phytin encapsulated in cell walls. The future of enzymes in nonruminant animal production is promising and will likely include an understanding of the role of enzyme supplementation in promoting health as well as how enzymes may modulate gene functions. This review is an attempt to summarize current thinking in this area, provide some clarity in nomenclature and mechanisms, and suggest opportunities for expanded exploitation of this unique biotechnology. [ABSTRACT FROM AUTHOR]

A total of 84 sows (PIC Line 1050) were blocked according to day of farrowing and parity and allotted in a 2 × 2 factorial arrangement of treatments with lactation feed intake (ad libitum vs. restricted) and creep feeding (no vs. yes) as factors. Sows fed for ad libiturn intake (ad libitum-fed) were allowed free access to a common lactation diet (3,503 kcal of ME/kg, 0.97% standardized ileal digestible Lys), and sows with restricted intake (restricted-fed) were fed 25% less than ad libitum-fed sows. A creep diet (3,495 ME/kg, 1.56% standardized ileal digestible Lys) with 1.0% chromic oxide was offered to creep-fed pigs from d 3 to 21. Fecal samples from creep-fed pigs were taken with sterile swabs on d 7, 14, and 21, and color was assessed to categorize pigs as eaters or non-eaters. There were no interactions (P > 0.15) between lactation feed intake and creep feeding. Ad libitum-fed sows had greater (P < 0.01) total feed intake and ADFI (99.4, 4.9 kg) than restricted-fed sows (67.9, 3.6 kg). Ad libitum-fed sows had reduced BW loss (-15 vs. -24 kg; P < 0.01), improved total (46.7 vs. 43.0 kg; P < 0.04) and daily (2.56 vs. 2.36 kg; P < 0.04) BW gains of litters, and increased (90 vs. 71%; P < 0.03) percentage of sows returning to estrus by d 14 compared with restricted-fed sows. Creep feeding for 18 d did not affect (P > 0.34) sow BW and backfat loss but increased days to estrus (5.4 vs. 4.9 d; P < 0.03). Creep feeding had no (P> 0.16) effect on preweaning growth performance. Postweaning performance of creep-fed and non-creep-fed pigs was similar (P > 0.86). When individual pigs were categorized on the basis of creep feed consumption category, eaters had greater (P < 0.05) ADG (393, 376, and 378 g) and total BW gains (11.0, 10.5, and 10.6 kg) than non-eaters or non-creep-fed pigs. In conclusion, creep feeding for 18 d did not affect preweaning and lactating sow performance. Low feed intake during lactation negatively affected sow and litter performance. Creating more creep-feed eaters during the lactation period may benefit postweaning performance. Therefore, dietary and nondietary factors that can enhance the proportion of eaters in litters should be investigated. [ABSTRACT FROM AUTHOR]

This study was conducted to determine the effect of reduced lactation length and supplemental milk replacer (MR) during high ambient temperatures. Thirty nine primiparous and 100 multiparous sows (PIC, Franklin, KY, C-22) were used in a 2 × 2 × 2 factorial arrangement of treatments. Treatments consisted of two lactation room temperatures (21°C [TN] and 32°C [HOT]), two lactation lengths (14 or 19 d), and two parity groups (primiparous, multiparous). Pigs were either: 1) sow-reared to 19 d or 2) sow-reared to 14 d, and then reared to 19 d with MR after sow removal. All sows were fed the same diet (1.07% lysine, 3,366 kcal of ME/kg). Sows were weighed and ultrasound for backfat thickness (BF) and longissimus muscle area (LMA) within 6 h after farrowing and at the time of sow removal (d 14 or 19). Pigs were individually weighed at weaning (d 19) and after a 47-d nursery period (d 66). Heat stress increased sow weight loss (-13.35 kg, P < 0.01) and decreased sow feed intake (4.63 kg/d, P < 0.01) during lactation compared with sows in TN (+4.5 kg and 7.5 kg/d, respectively). Early weaning (d 14) during heat stress decreased maternal weight loss (-10.1 vs. -16.6 kg, P < 0.01). Primiparous sows lost more BF in both environments (-2.60 vs. -1.56 mm, P < 0.05), and both parity groups lost more BF (-3.35 vs. -2.3 mm, P < 0.10) and LMA (-1.82 vs. -0.77 cm², P < 0.05) when lactating for 19 d in the HOT environment than those lactating for 14 d. Pigs nursing primiparous and multiparous sows in the HOT environment and provided MR had heavier individual 19-d weights (7.37 and 8.12 kg/ pig, respectively) than those nursing to 19 d (5.57 and 6.04 kg/pig, P < 0.01). Milk replacer decreased the difference normally observed in 19-d weights between primiparous and multiparous sow-reared pigs in TN. Pigs fed MR in both environments and nursing multiparous sows had improved weight gains in the nursery compared with pigs nursing sows to 19 d (428 vs. 406 g/d,... [ABSTRACT FROM AUTHOR]

The article focuses on a study conducted to analyze the impact of wide calcium and phosphorus ratios on weanling pigs' supplemental phytase efficacy. It refers to the use of 96 weanling pigs in a 4-wk experiment fed in combination with two Phosphorus levels and two phytase levels. It found 16% increase in phytase efficacy for bone measurements, improving performance and digestibility.

The article focuses on a study conducted to examine feed intake patterns during lactation in commercial swine herds. It refers to the use of a database containing 25,719 farrowing and 19,393 subsequent litter records of 30 commercial farms and daily feed intake records of 25,040 lactating sows. It found that substantial individual sow and farm variation in overall feed intake during lactation.