Feeding patterns, growth performance and carcass traits in group-housed growing-finishing pigs: the effect of terminal sire line, halothane genotype and age

Variability in feed intake the first days following weaning impacts gastrointestinal tract development, feeding patterns, and growth performance in nursery pigs

The present study investigated the effects of voluntary feed intake (FI) the first days after weaning on gastrointestinal development and protein fermentation the first week after weaning and growth performance and feeding patterns during the nursery phase. A total of 144 mixed-sex weaned pigs (24 ± 2 d old; 7.2 ± 0.8 kg body weight [BW]) were allocated to 12 pens with 12 pigs/pen. Each pen was equipped with an electronic feeding station for monitoring individual FI during a 40-d study. Pigs were classified based on their cumulative FI over the initial 3 d after weaning (FId1-3) being above or below their pen median FId1-3 (high = 919 ± 244 g or low = 507 ± 222 g FId1-3). Similarly, weaning BW classes (BW0; high = 7.72 ± 0.59 kg or low = 6.62 ± 0.88 kg BW) were created to study interactions with FId1-3. Two female pigs with either a high or a low FId1-3 per pen (n = 24) were selected for sampling at d6 and were used to study gastrointestinal development and fermentation products in the small intestine. Feeding patterns per day, FI, and growth performance were measured individually. Low FId1-3 pigs had lower (P < 0.05) daily FI during d0 to d8, d8 to d15, and d22 to d28, BW on d15, d22, d29, and d40, and average daily gain during d0 to d8, d22 to d29, and d29 to d40 compared to high FId1-3. High FId1-3 pigs increased (P < 0.05) the number of visits to the feeder between d1 to d13 and d31 to d35, and the time spent per visit only for d1 to d4 (P < 0.05). The daily rate of FI (g/min) was higher (P < 0.05) for High FId1-3 pigs on d6, d8, d9, and d10, and again several days later (d20 to d39). In addition, the high FId1-3 × high BW0 interaction improved daily FI during d18 to d40 compared to low FId1-3 × low BW0 class (P < 0.05). For the sampling on d6, low FId1-3 pigs had a lighter small intestine, colon, and pancreas, and reduced villi length, smaller villi surface area, and a lower number of goblet cells size in jejunum (P < 0.05), while concentrations of lactic acid, histamine, and cadaverine in small intestinal content were increased (P < 0.05). In conclusion, pigs with high FId1-3 became faster eaters with higher FI and growth rates toward the second half of the nursery, which was similar and additive for pigs with higher weaning BW. High FId1-3 was also associated with greater development of the gastrointestinal tract and a reduced protein fermentation 1-wk after weaning.

Effect of terminal sire line and timing second vaccination on effectiveness of immunocastration, performance, and carcass and meat quality

Performance (from 10 weeks until slaughter), carcass and meat quality, and effectiveness of immunocastration was compared in crossbred offspring of stress positive (BP+) and negative (BP-) Belgian Piétrain and Canadian Duroc (CD) given the second vaccination of Improvac® at different times (4, 6, 8 weeks before slaughter). CD offspring had a significantly higher daily gain (DG) and feed intake (DFI), and lower predicted lean meat percentage (LMP) and dressing yield compared to BP+ and BP-, while feed conversion ratio (FCR) did not differ. CD offspring had significantly lower drip loss and higher pH_i, intramuscular fat content than BP+ and BP- (except for pH_i). No significant effect of vaccination time on DG nor FCR was observed. Predicted LMP tended to increase as time-post injection decreased, while meat quality was minor affected. Earlier vaccination had no effect on the effectiveness of immunocastration based on testosterone and GnRH-binding.

Continuous Monitoring of Pigs in Fattening Using a Multi-Sensor System: Behavior Patterns

Simple Summary

The livestock sector seeks technologies and procedures to collect and manage data and information about its facilities and animals being the basis of the so-called precision livestock. The installation of unusual devices in commercial facilities, as well as the use of electronic feeding stations, allows observers to characterize the behavior pattern of each individual in order to improve farm management techniques and, therefore, its productivity. In this study, 30 Landrace pigs were monitored during the whole fattening period. Results from the study show that the ear skin temperatures of the animals can be used to distinguish animals with different thermal patterns. The parameters extracted from the feeding stations show consistent relationships between the parameters related to the frequency, size, and duration parameters, highlighting the differences in the feeding strategies.

Abstract

In this work, a complete fattening period (81 days) of a total of 30 Landrace pigs housed in two pens of a nucleus in Villatobas (Castilla-La Mancha, Spain) were supervised. The ear skin temperature of each animal was recorded every three minutes. The body weight, the date, the duration, and the amount of feed consumed per animal was monitored via an electronic feeding station. The objective was the identification of animals with different behaviors based on the integration of their thermal and intake patterns. The ear skin temperatures of the animals showed a negative relationship between the mean and the standard deviation (r = 0.83), distinguishing animals with different thermal patterns: individuals with high-temperature values show less thermal variability and vice versa. Feeding parameters showed differences in the feeding strategies of animals, identifying fast-eating animals with a high rate feed intake (60 g/min) and slow eaters (30 g/min). The correlation between the change in the rate of feed intake along with animal growth and feed efficiency reached a significant negative value (−0.57), indicating that animals that do not alter their rate of feed intake along breeding showed higher efficiencies. The difference in temperature of an animal with respect to the averaged group value has allowed us to identify animals with differentiated feeding patterns.

Analyses of body weight patterns in growing pigs: a new view on body weight in pigs for frequent monitoring

Frequent BW monitoring of growing pigs can be useful for identifying production (e.g. feeding), health and welfare problems. However, in order to construct a tool which will properly recognize abnormalities in pigs' growth a precise description of the growth process should be used. In this study we proposed a new model of pig growth accounting for daily fluctuations in BW. Body weight measurements of 1710 pigs (865 gilts and 843 barrows) originating from five consecutive batches from a Danish commercial farm were collected. Pigs were inserted into a large pen (maximum capacity=400) between November 2014 and September 2015. On average, each pig was observed for 42 days and weighed 3.6 times a day when passing from the resting to feeding area. Altogether, 243,160 BW measurements were recorded. A multilevel model of pig growth was constructed and fitted to available data. The BW of pigs was modeled as a quadratic function of time. A diurnal pattern was incorporated into the model by a cosine wave with known length (24 h). The model included pig effect which was defined as a random autoregressive process with exponential correlation. Variance of within-pigs error was assumed to increase with time. Because only five batches were observed, it was not possible to obtain the random effect for batch. However, in order to account for the batch effect the model included interactions between batch and fixed parameters: intercept, time, square value of time and cosine wave. The gender effect was not significant and was removed from the final model. For all batches, morning and afternoon peaks in the frequency of visits to the feeding area could be distinguished. According to results, pigs were lighter in the morning and heavier in the evening (minimum BW was reached around 1000 h and maximum around 2200 h). However, the exact time of obtaining maximum and minimum BW during the day differed between batches. Pigs had access to natural light and, therefore, existing differences could be explained by varying daylight level during observations periods. Because the diurnal amplitude for pig growth varied between batches from 0.9 to 1.4 kg, BW monitoring tools based on frequent measurements should account for diurnal variation in BW of pigs. This proposed description of growth will be built into a monitoring tool (a dynamic linear model) and applied to farm data in future studies.

Animal and management factors influencing grower and finisher pig performance and efficiency in European systems: a meta-analysis

A meta-analysis on the effects of management and animal-based factors on the performance and feed efficiency of growing pigs can provide information on single factor and interaction effects absent in individual studies. This study analysed the effects of such factors on average daily gain (ADG), feed intake (FI) and feed conversion ratio (FCR) of grower and finisher pigs. The multivariate models identified significant effects of: (1) bedding (P<0.01), stage of growth (P<0.001) and the interaction bedding×lysine (P<0.001) on ADG. ADG was higher on straw compared with no bedding (710 v. 605 g/day). (2) FI was significantly affected by stage of growth (P<0.01), bedding (P<0.01), group composition (P<0.05), group size (P<0.01), feed CP content (P<0.01), ambient temperature (P<0.01) and the interaction between floor space and feed energy content (P<0.001). Pigs housed on straw had a lower FI in comparison with those without (1.44 v. 2.04 kg/day); a higher FI was seen for pigs separated by gender in comparison with mixed groups (2.05 v. 1.65 kg/day); FI had a negative linear relationship with group size, the CP content of the feed and ambient temperature. (3) Stage of growth (P<0.001), feed CP (P<0.001) and lysine content (P<0.001), ambient temperature (P<0.001) and feed crude fibre (CF) content (P<0.01) significantly affected FCR; there were no significant interactions between any factors on this trait. There was an improvement in FCR at higher ambient temperatures, increased feed CP and lysine content, but a deterioration of FCR at higher CF contents. For ADG, the interaction of bedding×lysine was caused by pigs housed without bedding (straw) having higher ADG when on a feed lower in lysine, whereas those with bedding had a higher ADG when on a feed higher in lysine. Interaction effects on FI were caused by animals with the least amount of floor space having a higher FI when given a feed with a low metabolisable energy (ME) content, in contrast to all other pigs, which showed a higher FI with increased ME content. The meta-analysis confirmed the significant effect of several well-known factors on the performance and efficiency of grower and finisher pigs, the effects of some less established ones and, importantly, the interactions between such factors.

Effects of genotype and dietary oil supplementation on performance, carcass traits, pork quality and fatty acid composition of backfat and intramuscular fat

A 42-day study was conducted to evaluate the effect of genotype: terminal sire line Duroc×F1 (DC×F1); terminal sire line Embrapa MS-115×F1 (MS-115×F1); and MS-115×Moura (MS-115×MO) and three dietary oil sources: soybean; canola; and canola+flax, on performance, carcass traits, pork quality, and fatty acid composition. Genotype affected the technological quality of pork and fatty acid profile. MS-115-sired pigs had better meat color and Duroc-sired pigs had higher intramuscular fat content, more saturated fat and better omega-6/omega-3 ratio. Moura breed influenced positively meat tenderness and intramuscular fat. Diet did not affect the technological quality of the meat. Canola or canola+flax oil diet supplementations increased monounsaturated and C18:3 and decreased C18:2 fatty acids, reducing the omega-6/omega-3 ratio. The best omega-6/omega-3 ratio was obtained through supplementation with canola+flax.