Effect of vitamin levels and different stocking densities on performance, nutrient digestibility, and blood characteristics of growing pigs

Effect on Feeding Behaviour and Growing of Being a Dominant or Subordinate Growing Pig and Its Relationship with the Faecal Microbiota

Pigs are a social species, and they establish hierarchies for better use of resources and to reduce conflicts. However, in pig production, the opportunities for growth can differ between dominant and subordinate animals. In the present study, a system was tested to perform a dominant versus subordinate test in growing pigs to investigate how the hierarchy affects feeding behaviour, growth, and gut microbiota assessed in faeces. Sixty-four animals housed in eight different pens were used, with four castrated males and four females in each one, weighing 18 kg at arrival and maintained during the whole growing period, until 140 kg. Three stool samples were obtained from the animals directly from the anus to avoid contamination of the faeces 58, 100, and 133 days after the start of the study to investigate the microbiota composition. The dominant animals had higher gains during the growing period than the subordinates. In addition, they were performing more visits to the feeder throughout the day. Differential abundance patterns were observed in five bacterial genera, with Oliverpabstia, Peptococcus, and Faecalbacterium being more abundant in dominant animals and Holdemanella and Acetitomaculum being overrepresented in subordinate ones. This microbial biomarker accurately classified dominant versus subordinate groups of samples with an AUC of 0.92.

Effects of different stocking density and various phytogenic feed additives dosage levels on growing-finishing pigs

This study was to investigate the effects of different phytogenic feed additives (PFA) dosage levels in growing- finishing pigs stressed by high stocking density. A total of 72 mix sexed 12 weeks growing pigs ([Landrace × Yorkshire] × Duroc) with initial body weight (BW) of 49.28 ± 4.58 kg were used for 8 weeks. There were 3 replicate pens in each treatment group, with 3 pigs per pen. The dietary treatment groups consisted of basal diets in animal welfare density (negative control [NC]), basal diet in high stocking density (positive control [PC]), PC + 0.04% essential oil (ES1), PC + 0.08% essential oil (ES2), PC + 0.10% bitter citrus extract & essential oil (CES1), PC + 0.20% bitter citrus extract & essential oil (CES2), PC + 0.05% grape pomace extract (GP1), PC + 0.10% grape pomace extract (GP2). The reduction of space allowance decreased (p < 0.05) average daily gain, feed efficiency, and digestibility of dry matter, crude protein, and gross energy. Also, the fecal score of PC groups increased (p < 0.05) compared with other groups. Basic behaviors (feed intake, standing, lying) were inactive (p < 0.05) and singularity behavior (biting) was increased (p < 0.10) under high stocking density. There was no difference in blood profile. However, the supplementation of PFA alleviated the negative effects such as reduced growth performance, nutrient digestibility, and some increasing stress indicators in th blood (cortisol) and animal behavior (biting). In conclusion, the negative effect of high stocking density was most effectively mitigated by the normal dosage of the mixture of bitter citrus extract and essential oil additive (CES1).

Effects of group size and homeopathic product supplement consisting of botanicals and mineral mixture on the performance and production traits of finishing pigs

A total of 144 mixed sex pigs [(Landrace × Yorkshire) × Duroc] with an initial average body weight (BW) of 52 kg were used in a 11 wk trial in a 2 × 2 factorial design with the following factors: group size (three pigs per pen vs. five pigs per pen) and 0% or 0.2% homeopathic product supplementation to evaluate growth performance, nutrient digestibility, meat quality, and stress-related hormones. The homeopathic product supplementation resulted in increased (P < 0.05) BW at week 11, average daily gain (ADG) during days 42–63 and 64–77. In addition, an increase (P < 0.05) in ADG and average daily feed intake during overall experiment period and an increase (P < 0.05) in apparent total tract digestibility of dry matter at day 77 were observed in pigs receiving homeopathic product. A trend in increase (P = 0.088) in serum cortisol concentration during day 42 and increase (P > 0.05) during day 77 was observed in pigs with group size of five pigs per pen, and this was reduced when homeopathic product was supplemented to the diet. In conclusion, the variation in number of animals per pen had no effects on performance and production traits, but the animals in bigger group size had higher serum cortisol concentrations which were reduced by the homeopathic product supplementation.

Increased vitamin supplement to sows, piglets and finishers and the effect in productivity

With still limited information on vitamin requirements and considering that many commercial practices adopt dietary vitamin levels above the values suggested by nutritional tables, this study aimed to assess the effect of administering vitamin supplementation to sows in gestation and lactation and to their litters on the reproductive performance and body condition of the sows and on the performance and immune profile of the litters until slaughter. The trial was split into two phases. The first phase used 104 sows, assigned to be randomized to blocks according to parity, submitted until 21 days of lactation to two treatments: control-standard (standard levels of vitamins) and test-elevated (elevated levels of vitamins). Each sow and its respective farrow were considered an experimental unit. The sows underwent evaluations of body condition score, back fat thickness and reproductive performance. In the second phase, 60 barrows and 60 gilts at 21 days of age and mean initial weight of 5.33 ± 1.5 kg until slaughter at 164 days of age. The piglets were assigned to randomized blocks according to the weight and sex of the animals in a 2 × 2 factorial model, with 10 replicates per treatment, where a pen with three animals represented the experimental unit. Following the same treatments of the first phase, the piglets were evaluated for daily weight gain, daily feed intake, feed conversion, mortality rate and humoral immune response. Vitamin supplementation had no positive effects on the reproductive parameters or body composition of sows. However, it positively impacted the performance of the litters in the early nursery stage, but did not lead to superior effects on the immune responses to vaccination against circovirus or mycoplasma.

Redox Properties of Tryptophan Metabolism and the Concept of Tryptophan Use in Pregnancy

During pregnancy, tryptophan (Trp) is required for several purposes, and Trp metabolism varies over time in the mother and fetus. Increased oxidative stress (OS) with high metabolic, energy and oxygen demands during normal pregnancy or in pregnancy-associated disorders has been reported. Taking the antioxidant properties of Trp and its metabolites into consideration, we made four hypotheses. First, the use of Trp and its metabolites is optional based on their antioxidant properties during pregnancy. Second, dynamic Trp metabolism is an accommodation mechanism in response to OS. Third, regulation of Trp metabolism could be used to control/attenuate OS according to variations in Trp metabolism during pregnancy. Fourth, OS-mediated injury could be alleviated by regulation of Trp metabolism in pregnancy-associated disorders. Future studies in normal/abnormal pregnancies and in associated disorders should include measurements of free Trp, total Trp, Trp metabolites, and activities of Trp-degrading enzymes in plasma. Abnormal pregnancies and some associated disorders may be associated with disordered Trp metabolism related to OS. Mounting evidence suggests that the investigation of the use of Trp and its metabolites in pregnancy will be meanful.

Effects of different space allowances on growth performance, blood profile and pork quality in a grow-to-finish production system

Objective

This experiment was conducted to evaluate the optimal space allowance on growth performance, blood profile and pork quality of growing-finishing pigs.

Methods

A total of ninety crossbred pigs [(Yorkshire×Landrace)×Duroc, 30.25±1.13 kg] were allocated into three treatments (0.96: four pigs/pen, 0.96 m²/pig; 0.80: five pigs/pen, 0.80 m²/pig; 0.69: six pigs/pen, 0.69 m²/pig) in a randomized complete block design. Pigs were housed in balanced sex and had free access to feed in all phases for 14 weeks (growing phase I, growing phase II, finishing phase I, and finishing phase II).

Results

There was no statistical difference in growing phase, but a linear decrease was observed on average daily gain (ADG, p<0.01), average daily feed intake (ADFI, p<0.01), and body weight (BW, p<0.01) with decreasing space allowance in late finishing phase. On the other hand, a quadratic effect was observed on gain to feed ratio in early finishing phase (p<0.03). Consequently, overall ADG, ADFI, and final BW linearly declined in response to decreased space allowance (p<0.01). The pH of pork had no significant difference in 1 hour after slaughter, whereas there was a linear decrease in 24 h after slaughter with decreasing space allowance. Floor area allowance did not affect pork colors, but shear force linearly increased as floor space decreased (p<0.01). There was a linear increase in serum cortisol concentration on 14 week (p<0.05) with decreased space allocation. Serum IgG was linearly ameliorated as space allowance increased on 10 week (p<0.05) and 14 week (p<0.01).

Conclusion

Data from current study indicated that stress derived from reduced space allowance deteriorates the immune system as well as growth performance of pigs, resulting in poor pork quality. Recommended adequate space allowance in a grow-to-finish production system is more than 0.80 m²/pig for maximizing growth performance and production efficiency.