Supplemental Fermented Milk Increases Growth Performance of Early-Weaned Pigs

Dunshea, F.R.,Kerton, D.J.,Eason, P.J.,King, R.H. Asian Australasian Association of Animal Productio 2000 Animal Bioscience Vol.13 No.4

Early weaning is a means of breaking the disease cycle from sow to piglet as well as capitalising on the enormous growth potential of the pig. However, the transition from milk to dry diets results in a growth check. Feeding of supplemental milk, fermented to reduce pH and enterotoxigenic bactetial proliferation, may be a means of gradually weaning pigs on to solid feed. This study involved 216 pigs weaned from the sow at 12 days of age, allocated to groups of 6 males and 6 females per weaner pen and allowed ad libitum access to a pelleted diet. In addition, half the pigs were given supplemental fermented skim milk for the first 8 days after weaning. Feeding supplemental fermented milk increased feed intake (104 vs. 157 g DM/d, p=0.011), average daily gain (-3 vs. 112 g/d, p<0.001) and feed conversion efficiency (0.01 vs. 0.81, p=0.003) over the first 8 days after weaning. The improvements observed in the supplemented pigs continued to be augmented such that, by 42 days of age, the pigs that had received supplemental fermented milk were heavier (9.6 vs. 11.5 kg, p=0.003) than their unsupplemented counterparts. Feeding fermented supplemental milk to early-weaned pigs can improve growth performance in the immediate and subsequent post-weaning period.

Dietary Conjugated Linoleic Acid Can Decrease Backfat in Pigs Housed under Commercial Conditions

Dunshea, F.R.,Ostrowska, E.,Luxford, B.,Smits, R.J.,Campbell, R.G.,D'ouza, D.N.,Mullan, B.P. Asian Australasian Association of Animal Productio 2002 Animal Bioscience Vol.15 No.7

Conjugated linoleic acids (CLA) have been shown to decrease body fat content of individually-housed pigs but little is known about the responses under commercial conditions. Two studies were conducted to evaluate the effect of CLA under commercial conditions using contemporary genotypes. The experimental designs were similar between the two sites. Briefly, the studies were 2${\times}$2 factorial designs with the respective factors being sex (boar and gilt) and supplemental dietary CLA (0 and 4 g/kg). The studies involved 16-20 pens of pigs with 4-5 pens of each sex${\times}$CLA group. The first study was conducted with 144 pigs in 16 pens consuming a pelleted feed for 6 weeks at Bunge Meat Industries, Corowa, NSW. In the second study, 160 pigs were obtained from a commercial source and put into 20 pens in simulated commercial conditions and fed a mash diet for 7 weeks at Medina Research Station, WA. In Study 2 some aspects of meat quality were also investigated. Data from Study 1 showed that, although CLA had no significant effect upon feed intake and daily gain, the small changes in both resulted in a reduction in (-0.10 g/g, p=0.10) feed conversion ratio (FCR). While there was no significant effect of CLA on ultrasonic backfat depths, there was a significant decrease in carcass P2 (-1.0 mm, p=0.014) and estimated carcass fat (-7 g/kg, p=0.049). In the study conducted at Medina CLA had no significant effect upon feed intake, feed:gain or most measures of back fat. The exception was that dietary CLA decreased the rate of accumulation of fat at the shoulder, particularly in gilts, resulting in a significantly lower amount of shoulder fat at slaughter (-1.3 mm, p=0.044). CLA tended to increase dressing percentage although this was not significant (+0.5%, p=0.14). Meat from CLA treated pigs tended to be darker (p=0.12) and had a higher ultimate pH (p=0.06). These data suggest that under commercial conditions dietary CLA can improve growth performance and decrease P2 in pigs of an improved genotype, particularly gilts.

Sexual Dimorphism in Growth of Sucking and Growing Pigs

Dunshea, F.R. Asian Australasian Association of Animal Productio 2001 Animal Bioscience Vol.14 No.11

Three studies were conducted to determine the effect of sex on pre- and post-weaning performance of pigs. These studies were conducted in response to observations that female pigs appear to grow faster than male pigs after weaning. In addition, female pigs have been found to grow faster than male pigs when supplied with supplemental milk before weaning. The aims of the present work were to further characterise the ontogeny of sex differences growth of nursing and growing pigs. In the first study, piglets sucking 32 sows were crossfostered to produce litters of 10 boars (n=9), 10 gilts (n=l 1) or 5 boars and 5 gilts (n=12). Liveweight of the sucking pigs was then measured weekly until weaning at 4 weeks of age. In the second study, 80 boars and 80 gilts were weaned at 26 days of age and growth performance measured until 21 days post-weaning. In the third experiment, 40 boars and 40 gilts were weaned into groups of 5 pigs at either 17 or 25 days of age and pigs were weighed until they were approximately 90 kg liveweight. All-boar litters grew more slowly than the all-gilt and mixed litters such that by 14 days of age the all-boar litters were 10% lighter than the all-gilt or mixed litters (39 vs. 43.8 kg, p=0.050). The proportional difference in litter weight appeared to be maintained at 21 days of age (53.9 vs. 59.4 kg, p=0.063) but was diminished by 28 days of age (66.5 vs. 70.8 kg, p=0.28). In the second study, gilts grew more quickly than boars over the first 7 and 21 days post-weaning and as a consequence were 10% heavier than boars at 21 days after weaning (13.7 vs 12.48 kg, p=0.001). In the third study, gilts grew more quickly than boars in the immediate 7 days post-weaning (40 vs. 5 g/day, p=0.014) whereas from 7 until 35 days post-weaning there was no significant difference in growth rate (381 vs. 360 g/day, p=0.19). Gilts also grew more quickly than boars over the 14 days after being moved into the grower (631 vs. 570 g/day, p=0.013) and finisher (749 vs. 688 g/day, p=0.038) sheds. However, these differences were not maintained over the entire period in each shed. These data support the hypotheses that gilts handle the stresses of weaning and other transitions better than boars.

Colostrum Protein Isolate Increases Gut and Whole Body Growth and Plasma IGF-I in Neonatal Pigs

Van Barneveld, R.J.,Dunshea, F.R. Asian Australasian Association of Animal Productio 2011 Animal Bioscience Vol.24 No.5

The growth rate of the young pig is generally much less than it's potential and may be constrained by endocrine status as well as nutrient intake. Growth factors are present in relatively high quantities in colostrum and play an important part in gut development. It is possible that supplementation of colostrum protein isolate may stimulate gut and whole body growth in the pig. Eight male and 8 female (Large Whitex${\times}$Landrace) piglets were weaned at 1 d of age after each pig had obtained colostrum from their dam, and were trained to consume one of two liquid diets. The two diets were based on either a colostrum protein isolate (n = 4 males and 4 females) or whey protein concentrate (n = 4 males and 4 females) and were formulated to contain equal levels of crude protein and amino acids. Pigs were fed their diets ad libitum for 28 days after which time 12 pigs were euthanised and various tissues and organs weighed. Pigs were bled for IGF-I analyses at 21 and 28 days of age. Daily gain was higher in pigs consuming the colostrum isolate (171 vs. 216 g/d, p = 0.010), particularly between 2 and 4 weeks of age (212 vs. 298 g/d, p = 0.010). Pigs tended to consume more of the liquid feed containing colostrum isolate (25.5 vs. 29.1 kg, p = 0.074) and gained more live weight per unit of liquid feed (0.203 vs. 0.223 g/g, p = 0.056). There were no effects of sex on growth performance. Pigs consuming the diet supplemented with colostrum isolate had higher (p<0.05) full gut weight (445 vs. 554 g, p = 0.026), empty gut weight (356 vs. 463 g, p = 0.008), stomach weight (42.2 vs. 54.4 g, p = 0.001), small intestine weight (222 vs. 275 g, p = 0.025) and large intestine weight (63.7 vs. 98.0 g, p = 0.005). Plasma IGF-I (99 vs. 150 ng/ml, p<0.001) and IGF-II (265 vs. 406 ng/ml, p<0.001) were higher in pigs fed colostrum isolate. Pigs consuming colostrum protein isolate ate more, grew faster and had higher plasma IGF-I concentrations than pigs consuming a diet with similar macronutrient content but devoid of growth factors.

A short-term supranutritional vitamin E supplementation alleviated respiratory alkalosis but did not reduce oxidative stress in heat stressed pigs

Fan Liu,Pietro Celi,Surinder Singh Chauhan,Jeremy James Cottrell,Brian Joseph Leury,Frank Rowland Dunshea 아세아·태평양축산학회 2018 Animal Bioscience Vol.31 No.2

Objective: Heat stress (HS) triggers oxidative stress and respiratory alkalosis in pigs. The objective of this experiment was to study whether a short-term supranutritional amount of dietary vitamin E (VE) can mitigate oxidative stress and respiratory alkalosis in heat-stressed pigs. Methods: A total of 24 pigs were given either a control diet (17 IU/kg VE) or a high VE (200 IU/kg VE; HiVE) diet for 14 d, then exposed to thermoneutral (TN; 20°C, 45% humidity) or HS (35°C, 35% to 45% humidity, 8 h daily) conditions for 7 d. Respiration rate and rectal temperature were measured three times daily during the thermal exposure. Blood gas variables and oxidative stress markers were studied in blood samples collected on d 7. Results: Although HiVE diet did not affect the elevated rectal temperature or respiration rate observed during HS, it alleviated (all p<0.05 for diet×temperature) the loss of blood CO2 partial pressure and bicarbonate, as well as the increase in blood pH in the heat-stressed pigs. The HS reduced (p = 0.003) plasma biological antioxidant potential (BAP) and tended to increase (p = 0.067) advanced oxidized protein products (AOPP) in the heat-stressed pigs, suggesting HS triggers oxidative stress. The HiVE diet did not affect plasma BAP or AOPP. Only under TN conditions the HiVE diet reduced the plasma reactive oxygen metabolites (p<0.05 for diet× temperature). Conclusion: A short-term supplementation with 200 IU/kg VE partially alleviated respiratory alkalosis but did not reduce oxidative stress in heat-stressed pigs.