Weaning imposes stress that affects pig health and, thus, performance, according to T. van Kempen and J.-W. Resink of Nutreco and North Carolina State University, and the prime problem appears to be piglets' adaptation to eating solid feed.
Van Kempen and Resink presented poster TH420 at the recent joint annual meeting of the American Society of Animal Science and American Dairy Science Assn. that examined the eating patterns of newly weaned piglets.
They said to better understand how pigs start eating, 96 piglets were weaned at 25 days of age at 10 a.m. Pigs were placed into eight pens equipped with feeding stations with a measuring accuracy of 1 g. Visits and cumulative feed disappearance were recorded for each piglet: The first 10 g was considered their first meal and the second 10 g their second meal.
The researchers said light was on continuously the first 24 hours, and afterward, a 16 hours of light/eight hours of dark pattern was introduced; feeders, however, were permanently lit.
According to van Kempen and Resink, 93 piglets visited the feeder on the day of weaning, while the remaining three waited until the next morning. Seventy-eight piglets consumed their first meal the day of weaning, nine the next day and the remaining nine on the second day.
On the day of weaning, the average feed disappearance was 2.6 g and the largest feed disappearance recorded was 22 g, the researchers said.
Despite 24 hours of light, there were nearly no feeder visits between 8 p.m. and 4 a.m. on the first night, van Kempen and Resink reported. The next day, a clear day/night pattern was discernible as well, but there were approximately 10 times more feeder visits during nighttime hours.
The researchers noted that 77 piglets finished both their first and second meals on the first day. Interestingly, the second meal occurred 50% later than the first meal (r-square of 0.98). Piglets that did not finish their second meal before 8 p.m. waited to finish that meal until the next morning (after 6 a.m.), when a linear relationship again was observed between the time until the first meal and the second meal, van Kempen and Resink said.
Pigs that waited until the second day for their first meal ate their second meal only at the end of the second day or on the third day; none of these pigs ate a meal at night, the researchers added.
According to van Kempen and Resink, the data show that, immediately upon weaning, pigs change to a day/night feed intake pattern despite 24 hours of light in the nursery. Pigs that were hesitant to start eating did so carefully. The lag time between the first 10 g and second 10 g of feed disappearance was 50% of the time it took to the first 10 g of feed disappearance.
The time of day that piglets are weaned may affect their transition time to solid feed, they concluded.
Researchers at McNeese State University in Lake Charles, La., are continuing research into the immunological effects of alligator blood in young piglets (Feedstuffs, June 23, 2007).
S. Means, B. Chung, T. Shields and F. LeMieux of McNeese presented poster TH413 that examined the immunological and growth response in preweanling piglets administered an oral gavage of alligator blood.
Means et al. randomly allocated 18 crossbred pigs from two litters to a control group (tap water) or the treatment of alligator blood gavage. Pigs were administered 5 mL of an oral gavage twice daily for the three days prior to weaning.
Pig weights were recorded at days -3, 0 (day of weaning), 3, 7 and 14 to determine average daily gain. Additionally, blood samples were taken on days -3 and 0 to evaluate blood chemistry (glucose, blood urea nitrogen, creatinine, phosphorus, total protein, albumin and globulin), and enzyme-linked immunosorbent assay testing was conducted to determine immunoglobulin levels (IgG, IgA and IgM), Means et al. said.
Treatment did not affect (P > 0.10) pig growth, the researchers reported. Pigs on the control treatment had increased levels of glucose, phosphorus, total protein, albumin and globulin over the three-day treatment period. Pigs receiving alligator blood had a 12.02% decrease in blood glucose, compared with an increase of 2.7% for the control pigs, over the three days. Globulin levels decreased 13.23% in pigs administered alligator blood versus a decrease of 19.24% in the control pigs.
After three days of treatment, serum immunoglobulin levels of IgG were lower (P < 0.05) in pigs receiving the alligator blood treatment, Means et al. said, noting that IgG levels in pigs receiving alligator blood decreased 32%, which was double the 14% decrease in pigs receiving control treatments. IgA levels were also lower (P < 0.05) in pigs receiving the alligator blood gavage, but there was no difference (P > 0.10) in IgM levels, they said.
Means et al. concluded that alligator blood may be a beneficial additive for nursing and weanling pigs.
In research on the immune status of nursery pigs, Oklahoma State University researchers M.R. Bible, S.D. Carter, K.F. Coble, H.J. Kim and T.M. Walraven presented abstract W339 on the potential of turmeric compounds to improve the growth and immune response of nursery pigs.
Bible et al. explained that curcumin is an active component in turmeric that has antimicrobial and anti-inflammatory properties and noted that it may aid in improving the growth performance of nursery pigs.
They used 216 crossbred pigs that were weaned at 20 days of age and allotted the pigs randomly to four dietary treatments in a randomized, complete block design. Bible et al. said standard corn/soybean meal-based diets were fed in meal form in a four-phase feeding program. The treatment diets were a negative control (no antibiotic), a positive control (55 mg/kg of carbadox), the negative control plus 2 g/kg of turmeric powder and the negative control plus 80 mg/kg of curcumin powder. Carbadox, turmeric and curcumin replaced corn in the respective diets.
Average daily gain, average daily feed intake (ADFI) and gain:feed were calculated for days 0-21 and 0-42. On day 20, one pig from each pen was challenged with Escherichia coli lipopolysaccharide (LPS). Rectal temperatures were measured and blood collected for analysis of tumor necrosis factor-alpha (TNF-a) at 0, 3, 6, 12 and 24 hours post-injection.
For days 0-21, average daily gain for pigs on the carbadox (324 g) treatment was greater (P < 0.05) than for pigs on the control (294 g) or turmeric (293 g) treatments, with pigs on the curcumin (317 g) treatment intermediate, Bible et al. reported.
There was a tendency (P < 0.10) for ADFI to be lower for pigs fed turmeric (453 g) than pigs fed carbadox (489 g), with pigs fed the control (466 g) and curcumin (468 g) intermediate, the researchers said.
Pigs fed curcumin (0.68) had greater (P < 0.05) gain:feed than pigs fed control (0.63), with gain:feed similar for pigs fed carbadox (0.66) and turmeric (0.64).
Results for days 0-42 were similar to days 0-21, but with no effects on ADFI, Bible et al. said.
According to the researchers, rectal temperatures and TNF-a increased (P < 0.01) from LPS injection, peaked after three hours and returned to normal by 24 hours after LPS injection. For TNF-a, pigs fed curcumin had the smallest increase (P < 0.01) three hours after injection, followed by carbadox, the negative control and turmeric.
Bible et al. concluded that pigs fed curcumin had similar growth performance as those fed carbadox, and curcumin blunted the response to the LPS challenge.
K. McCormick and O. Adeola of Purdue University conducted a study to evaluate the effect of three antimicrobials on total-tract utilization of energy and phosphorus (abstract W338).
McCormick and Adeola said an improvement in energy and nutrient utilization may be contributing factors in the growth-promoting benefits of antimicrobials.
They used 24 barrows with an initial bodyweight of 17 kg that were housed in metabolism crates and assigned in a randomized, complete block design to dietary treatments that included: (1) a negative control, (2) control plus 55 g per ton of carbadox, (3) control plus 44 g per ton of tylosin and (4) control plus 11 g per ton of virginiamycin.
The control diet contained 0.7% calcium and 0.4% total phosphorus. Pigs were fed twice daily at an allowance of 4% of bodyweight. A five-day adaptation period preceded a five-day total collection period, with chromic oxide used as a marker to determine initiation and termination of fecal collection.
According to McCormick and Adeola, the results showed that antimicrobial supplementation did not affect dry matter digestibility, phosphorus absorption, dry matter retention or phosphorus retention.
Compared to pigs fed the negative control diet, supplementation of carbadox resulted in an increase in energy digestibility, at 86.5% versus 88.1% (P = 0.02), and energy retention, at 83.4% versus 84.9% (P = 0.03), McCormick and Adeola reported. Furthermore, supplementation of virginiamycin showed a tendency to improve energy retention relative to the negative control diet, at 83.4% versus 84.5% (P = 0.10).
They concluded that carbadox improved energy utilization, whereas virginiamycin improved energy retention, although there were no changes in dry matter and phosphorus utilization.