Heavier Piglets Research Articles

Implications of commercial cross-fostering in large litters when low body weight of piglets is the main criterion

Litter management aimed at reducing losses is crucial in intensive pig production, with cross-fostering (CF) being a commonly used approach. CF is a major challenge, especially in the breeding of highly prolific sows. We therefore investigated the efficiency of non-experimental CF under farm conditions. A total of 360 piglets (Choice Genetics − Naima sows × P76 boars) from 25 sequential litters were included in the observational study. Four litters with 48 piglets represented the control group and in the remaining 21 litters, 51 piglets (CF piglets) were cross-fostered according to the farm's standard procedure of mixing litters by body weight. The piglets were transferred to a specific foster sow in a way that piglets from 2 to 10 different litters were mixed. The CF piglets were lighter than the residents and the control piglets. The piglets that died had lower body weight than the survivors, especially in the CF group (≈35 %). Half of the CF piglets died a few days after birth, while mortality was 13 % in the residents and 8 % in the control group, resulting in a tendency of higher mortality in CF litters (19 %) compared to the control group. The unusually high mortality was mainly related to CF litters with more than two litters combined. Therefore, combining multiple litters and the use of low piglet birth weight as the main CF criterion does not seem to be justified from both a production and welfare point of view and could even have the opposite effect and increase mortality. To reduce mortality, other strategies could be tested (e.g. moving heavy piglets) and/or other CF criteria considered (e.g. teat order, litter size, parity).

Social networks of pregnant gilts during outdoor feeding and the effects on their offspring

Social relationships are important aspects of the behavioural biology of pigs and can be affected by the type of housing pigs are kept in. Exploring agonistic interactions and affiliative behaviours can reveal effects on adult pigs and their descendants. This research investigated the social dynamics among gilts throughout pregnancy during collective feeding in an outdoor housing system and the effects of these dynamics on the stability of the group and the offspring of the group members. For this study, 15 gilts were oestrus synchronised and artificially inseminated with three different semen pools. The paddocks where the gilts were housed contained a mud pool, natural tree shade, and two nipple drinkers. Two daily meals (∼2.5 kg/day/gilt) were provided to the group on the floor. Feeding behaviour was recorded for three continuous days (20 min in the morning and again in the afternoon) every gestational (a total of 42 h of video recording). Saliva samples were collected at 6:00 a.m. and 6:00 p.m. on these same days. A trained observer evaluated all the videos using Boris software to determine agonistic and affiliative behaviours. After farrowing, the piglet data collected included sex, mortality, and body weight (BW) at 10, 25, 29, and 36 d of age. Elo scores were calculated to quantify the relative hierarchy among the gilts based on the behaviour assessment. Generalised linear mixed models (GLMMs) were used for data analyses, and the significance of fixed effects was determined at p < 0.05. The tendency of the gilts to feed together decreased as gestation progressed. Heavier gilts had lower salivary cortisol concentrations, and higher gilt rank was correlated with higher morning salivary cortisol concentrations and heavier piglets. Maternal modulation of offspring performance in pigs warrant further investigation. Assessment of gilts' social feeding behaviours is relevant for considering pigs' behaviour in genetic selection and improving commercial facilities and management practices to improve animal welfare.

Sow and litter performance after cross-fostering one surplus piglet and co-mingling the litters at early lactation

The number of piglets born alive is frequently greater than the functional teats, and some farms are equalizing litters with surplus piglets, limiting piglet udder access. Removing the barrier among farrowing crates may allow piglets to socialize and seek other sows. Thus, we evaluated the effects litter size at cross-fostering and socialization on the sow and piglet performance during lactation. Two factors were included in a 2 × 2 factorial design: socialization and litter size relative to sow functional teat number at cross-fostering. Litters (n = 189) were then assigned to one of four groups: CONT+0 (litters not co-mingled with no additional piglet), CONT+1 (not co-mingled with one additional piglet), Co-M+0 (co-mingled with no additional piglet), Co-M+1 (co-mingled with one additional piglet). Piglets were cross-fostered from 12–16 h after birth, and 24 h later, Co-M groups were socialized by removing the barrier between two adjacent pens. During lactation, sows lost more caliper units in the + 1 group than in the + 0 group (P = 0.04). The number of functional teats did not differ among groups, but Co-M sows had a higher udder lesion score at weaning than CONT (6.55 vs 4.83; P < 0.01). Furthermore, +1 sows had fewer vacant teats throughout lactation (P < 0.01). Milk yield did not differ among the groups (P ≥ 0.13). Regarding the number of weaned piglets, no difference was observed for socialization (P = 0.84), but + 1 sows weaned 0.67 more piglets than + 0 (P < 0.01). Although CONT+0 had the heaviest piglets at weaning (P < 0.01), litter weight did not differ among the groups (P ≥ 0.08). Facial and joint lesions were frequently observed in Co-M (P < 0.01) than CONT. Piglet loss rate did not differ among treatments (overall rate = 12.6%; P ≥ 0.26). The removal rate, however, was more frequent in + 1 litters than in + 0 (P < 0.01). Death due to starvation was higher in CONT+1 than CONT+0 (P < 0.01) but did not differ between the Co-M groups (P = 0.99). Litters formed with one additional piglet relative to functional teat number weaned more piglets, albeit with lower individual weight. Litter socialization may alleviate the impact of high litter size but shows greater percentages of udder injuries and facial and joint lesions in weaned piglets.

Prevention of umbilical outpouchings and mortality in pigs: Meloxicam, tying, cutting, and chlorhexidine versus amoxicillin or no treatment? A clinical field trial

BackgroundUmbilical outpouchings (UOs) are common in Danish pigs. Neonatal antibiotics are therefore used with the hope of reducing umbilical infections and subsequently UOs. However, the effect of neonatal antibiotics on preventing UO has been the subject of mixed conclusions, and secondly, treating all animals with antibiotics might exacerbate the development of antimicrobial resistance.This study analysed the effects of different treatments on the prevalence of umbilical outpouchings and mortality from birth to nursery unit. All treatment was on the day of birth. The groups were: a negative control group, an antibiotic group receiving amoxicillin, and an experimental group where the piglets had their umbilical cord disinfected with chlorhexidine, followed by tying and clipping, and lastly, injection with meloxicam. The pigs were examined six weeks after weaning, and all pigs that died during the study were autopsied.ResultsThere were 5494 pigs divided across the three groups. There were no statistically significant differences in UO prevalence between the groups: control 3.9%, antibiotic 4.2%, and experimental 4.0% (p = 0.87). The only variable affecting the prevalence of UOs in this study was sex with females being at higher risk. There were no statistically significant differences in mortality between the groups from birth until departure from the nursery unit: control 22.9%, antibiotic 21%, and experimental 21.4% (p = 0.33). The variables affecting mortality were sex, intrauterine growth restriction (IUGR), birth weight, and cross fostering. Males had higher odds of dying, as had piglets recorded with some degree of IUGR. Also, low birth weight increased the odds of dying for all weight quartiles compared to the fourth (the heaviest piglets > 1.6 kg), as well as cross fostering increased the odds ratio of dying.ConclusionsThis study found no significant differences in the prevalence of UOs and mortality following different treatments at birth. The study showed that the prevalence of UO and mortality was not reduced following the administration of amoxicillin or meloxicam in combination with disinfection and tying of the umbilical cord.

Blending gestation and lactation diets during the transition period reduces energy mobilization by sows in late gestation, with no impact on subsequent lactation performance.

Fifty-three gilts and fifty-three multiparous (MP) sows were used to evaluate a blended feeding program using gestation and lactation diets during the transition period on changes in sow back fat (BF) depth and BW, blood metabolites, and litter growth performance in the subsequent lactation period. A 2 × 2 factorial experimental design was generated including the factors of parity and feeding program. The MP sows and gilts were assigned to one of two feeding programs on day 104 ± 1 of gestation: 1) 2kg/d of a standard lactation diet until farrowing when sows received step-up access to the lactation diet until ad libitum access was given on day 4 of lactation (CON) and 2) a dynamic blend of standard gestation and lactation diets that met estimated daily requirements for standardized ileal digestible Lys and net energy according to the NRC (2012) until day 4 of lactation where sows were provided ad libitum access to the lactation diet (TRAN). Litters were standardized to 13 ± 1 piglets within 24-h of birth. In gestation, ADFI was greatest for TRAN-MP sows (interaction; P < 0.05), with greater ADFI for TRAN versus CON sows (main effect; 2.95 vs. 2.13 ± 0.08kg; P < 0.05). Feeding program did not influence ADFI in lactation, but MP sows had greater ADFI versus gilts (main effect; 5.96 vs. 4.47 ± 0.28kg; P < 0.001). Immediately after farrowing, TRAN sows had greater BW and BF vs. CON sows, regardless of parity (main effect; 224.1 vs. 215.4 ± 4.1kg and 17.3 vs. 16.2 ± 0.4mm, respectively; P < 0.05). At weaning, no feeding program-related differences were observed for BW or BF, but MP sows had thicker BF compared to gilts (main effect; 14.4 vs. 13.4 ± 0.5mm; P < 0.05). The TRAN-MP sows had heavier piglets at birth compared to all other groups (interaction; P < 0.05) and MP sows had greater litter birth weight and average piglet BW at birth versus gilts (main effect; P < 0.05). No effect of feeding program was observed for piglet BW at weaning. On lactation day 1, serum beta-hydroxybutyric acid and non-esterified fatty acid concentrations were lower for TRAN compared to CON sows (main effect; 12.0 vs. 19.4 ± 7.8 mmol/L and 0.35 vs. 0.57 ± 0.10 mmol/L, respectively; P < 0.05) and serum glucose concentration was greater for TRAN compared to CON sows (main effect; 4.41 vs. 3.88 ± 0.22 mmol/L; P < 0.05), but these differences were no longer detectable at weaning. Therefore, a simple transition feeding program using a blend of a standard gestation and lactation diets reduced energy mobilization by sows in late gestation, with no impact on subsequent lactation performance.

Effect of Rye for Transition Sows on the Level of Piglet Serum Immunoglobulin Immunocrit

A sustainable increase in livestock productivity cannot be achieved without the use of sustainable animal feed. Due to the growing awareness of the long-term benefits of sustainability, there is an increasing interest in replacing traditional feed resources with the most sustainable feedstuffs in pig production. Rye production is relatively sustainable compared to wheat. This farm study investigated whether the newborn body weight as well as antibody transfer in piglets (serum immunoglobulin immunocrit) are affected by feeding rye instead of wheat grain to transition sows. A total of 237 sows and their piglets (n = 711) from three farms located in northern Germany participated in this study. During the transition period, the sows were fed either a wheat-based diet used as the control diet (CON) or a 30% rye diet (RYE) for 7 days before the calculated farrowing date. On the day of farrowing, piglet body weights within 24 h post-natal (PN) were recorded, and blood samples were taken from the lightest, medium, and heaviest piglets in each litter to determine the quantification of immunoglobulins in the piglets. Feeding rye-based diets to the sows showed no differences in the body weight of the newborns (within 24 h) compared to the CON group in all body weight categories, except on Farm C in light and medium piglets, where high BW were observed in the CON group. The immunocrit ratio did not show any differences between both feeding groups. A relationship between newborn body weight and immunocrit ratios in the CON and the RYE groups was observed only on farm A. Overall, this study showed that including amounts of rye up to 30% in sows’ diets during the transition period had no negative effects on newborn piglet body weight or on antibody transfer and therefore can be considered an adequate replacement for wheat (up to 30%) in diets for transition sows. However, future research is needed to determine whether a higher proportion of rye may be used.

Suckling Behaviour of Piglets Affected by Body Weight and Sex

Piglet suckling behaviour has been extensively studied, but surprisingly, there are not many studies that specifically consider body weight and sex in this context. These two basic individual characteristics have been considered more as supporting data but not as main factors. Therefore, the objective of the present research was to examine the effect body weight on suckling behaviour of piglets during lactation separately by sex. The study comprised 14 litters with a total of 158 piglets (85 male, 73 female, litter size 6−15 piglets). Suckling behaviour was described in terms of suckling position (the teat at which the piglet suckled during suckling), suckling territory (the range two outermost suckling positions of the piglet encompasses) and sucklingstability (the tendency to suckle successively at the same position), and was observed in six periods: 0−3, 4−7, 8−10, 11−14, 15−21 and 22−32 days of age. In each period, piglets were also weighed. The udder was divided into three areas: anterior (1st-2nd teat pair), middle (3rd-5th teat pair) and posterior (6th-8th teat pair). Body weight affected suckling behaviour differently in male and female piglets (i.e., all traits in females, suckling stability only in males). The relative body weight of females decreased significantly from the anterior towards the posterior part. Heavy females (but not males) suckled considerably more frequently on the anterior area. Heavier piglets (male and female) established more stable suckling order. Suckling territory of males was quite large, but did not differ among body weight classes. Interestingly, light females visited significantly larger suckling territory than heavy females. The present results fill a gap in the otherwise broad knowledge of pig suckling behaviour, which is of great importance for litter management during lactation, especially when cross-fostering is implemented. In this context, knowledge of the detailed role of sex and body weight is of particular importance because breeders rely mainly on basic body traits when managing litters.

Genetic parameters for early piglet weight, litter traits and number of functional teats in organic pigs.

Knowledge remains limited on genetic variation and genetic correlations for traits in sows and piglets that are reared in an organic or outdoor setting. Here, we estimated genetic variance components for individual piglet weight, litter weight, litter size traits, and number of functional teats in a pig population raised under outdoor organic conditions. Data were collected from the largest organic multiplier farm in Denmark. Individual piglet weight was recorded at birth and on day 10. Number of live and dead piglets were recorded at birth, day 4, and day 11. Mean and total litter weight were calculated based on the individual weight of living piglets at birth and on day 10. The estimated heritability was highest for the number of functional teats (0.49), mean weight of a litter at birth (0.33) and on day 10 (0.25). In contrast, heritability was lowest for litter size traits (0.04-0.08) and piglet weight (0.06-0.07). Maternal heritability was much higher for individual piglet weight than direct heritability. The results showed that selection for higher mean weight results in smaller litters. Also, selection for individual birth weight of piglets results in heavier piglets at 10days. In conclusion, this study confirmed that there is genetic variation in individual piglet weight, litter traits, and number of functional teats in organically and outdoor-reared pigs.

Effects of timing of grouping and split-weaning on growth performance and behaviour of piglets in a multi-suckling system

Variation in body weight (BW) of piglets at weaning is a drawback for successful implementation of multi-suckling (MS) systems. The current study investigated the combination of two intervention strategies, i.e. the timing of grouping and split-weaning, aiming to improve the BW gain of low birthweight piglets in an MS system and thereby reduce the BW variation at weaning on day 48 postpartum (p.p.). Eight batches of 5 sows with their litters were divided into 4 control (CTRL) and 4 treatment (TREAT) batches. In each litter, the second lowest (LBW) and highest (HBW) birthweight piglets from both sexes were selected as focal piglets. CTRL piglets were grouped on day 8 p.p. and no split-weaning was applied; TREAT piglets were grouped on day 13 p.p. and the three heaviest non-focal piglets per litter were split-weaned on day 35 p.p. Behaviour and feed intake were measured in focal piglets, and BW and mortality were measured in all piglets. Results showed that: (1) Throughout lactation there were no differences in BW or BW gain between CTRL and TREAT, nor were birthweight × treatment interactions found. (2) After grouping, there were no obvious differences between CTRL and TREAT in feeding and suckling behaviours on day 18, damage scores on snout, ear or tail and skin lesions on day 27, nor were birthweight × treatment interactions found. (3) After split-weaning, in week 6, piglets in TREAT tended to consume less feed than CTRL (P = 0.072). Low birthweight piglets in TREAT consumed numerically less feed and spent numerically less time contacting feed during the day than CTRL piglets. In week 6, there was a significant birthweight × treatment interaction in dry matter milk intake (P = 0.030), caused by a higher milk intake of TREAT-LBW piglets compared with CTRL-LBW piglets. In week 6, TREAT piglets tended to be present more at front and middle teats (P = 0.052) and tended to have lower snout damage scores (P = 0.084) than CTRL piglets. (4) Piglet crushing of all piglets in TREAT tended to be higher during the period when TREAT piglets were not yet grouped i.e. during days 9–14 than CTRL (P = 0.087). To conclude, split-weaning of the heavy piglets increased milk intake particularly of low birthweight piglets but this did not lead to a reduction in BW variation at weaning, as the increased milk intake was largely compensated for by a simultaneous decrease in feed intake.

Short- and Long-Term Effects of Birth Weight and Neonatal Care in Pigs.

Swine industries worldwide face a loss in profit due to high piglet mortality, particularly as a consequence of the marked increase in prolificity and low birth weight (BW) of piglets. This research studied the effect of BW and individual neonatal care provided to piglets on preweaning mortality, and the long-term effects on growth and carcass and meat characteristics. Litters from seventy-one crossbred sows (PIC 34) were included in the trial. Half of each litter did not receive any further management, and the remaining half received the pre-established management protocol of early assistance of neonatal care (NC). Along lactation, the low-BW piglets (weight equal to or less than 1.1 kg) showed a threefold higher mortality rate than piglets of higher weights (32 vs. 10%; p = 0.001), with mortality particularly concentrated within the first week after birth. No effect of NC treatment was observed on mortality ratio caused by crushing, but a significant effect was observed in low-BW piglets who died of starvation (p &lt; 0.01). The effect of NC on growth is dependent on BW, and heavier piglets at birth benefit from NC treatment to a higher extent than low-BW piglets. Low-BW piglets showed a higher fatness (p = 0.003), lower lean cut yield (p = 0.002) in carcasses, and higher intramuscular fat (IMF) content (2.29% vs. 1.91%; p = 0.01) in meat. NC treatment increased the lean content in carcasses from low-BW piglets (p &lt; 0.01). The monounsaturated fatty acids concentration was higher in lower-than-normal-BW piglets (48.1% vs. 47.1%; p = 0.002) and the opposite effect was observed for polyunsaturated fatty acids (13.6% vs. 15.7%; p = 0.002). NC treatment induced a higher concentration of n-7 fatty acids. In conclusion, NC treatment may be a useful practice to reduce mortality in low-BW piglets. Moreover, NC could affect carcass fatness and meat quality, thus suggesting a long-term effect on metabolism.

The influence of large-scale loss of piglets on their some meat and felting qualities

Purpose: the goal is to study in the piglets of a large white breed of influence of body weight at birth (large-way) on the thickness of the scraping and the age of achieving the live weight of 100 kg.Materials and methods. The object of the study - piglets (hrying and pigs) of a large white breed from birth until they achieve a live mass of 100 kg. The growth and development of piglets-sausage was studied by weighing them at birth. Primary data included 4215 weight records at the birth of tribal purebred piglets of a large white breed (hrying and pigs). Posyat, both live births and stillborn, weighed individually within 24 hours from the moment of birth. Weighing was carried out on scales with an accuracy of 100 g. The conditions of detention and feeding were the same. Three groups of experimental animals were formed, taking into account the live masses at birth. The first group was made up piglets with low live weight (1.0 kg and lower), the second - piglets with a normal body weight at birth (from 1.1 to 1.9 kg) and were divided into nine subgroups of 0.1 kg, the third - individuals with high live weight (2.0 kg and above). The thickness of the strika was measured in a lifestyle-meater ultrasonic device in the region over 6-7 breast vertebrae when a live mass of 100 kg is achieved (in the range of 60 kg to 150 kg).Results. It has been established that the floor of the animal, multipleness, month-year of birth, herd, liveborn or stillborn piglets in litter affect the average weight of the birth of piglets, as well as the thickness of the scraping and the number of days to achieve a live weight of 100 kg. The difference in weight at birth between the floors was insignificant, and the males were somewhat heavier piglets. Piglets 3 groups have had a higher average weight at birth compared to piglets 1 and 2 groups. Bible weight decreased when the size of the litter increased with 4 piglets (n = 54) to 17 piglets (n = 22). Piglets with a low live weight at birth had the most thick thickness of the striking at a weight of 100 kg and the longest was taken to 100 kg. In animals with high body weight at birth was the thinnest thickness of the strik, and it took the least day to reach the live weight of 100 kg. The thickness of the strip that pigs with a living weight of 100 kg decreased with an increase in body weight at birth. In pigs with a low live weight at birth, the strik thickness was 0,5 mm thicker (p≥0,999) compared with pigs weighing 1.4 kg and 1.5 mm thick stuck (p≥0,999) compared with the 3rd group. A significant correlation -0,20 was found between the live body weight at birth and the thickness of the scraping when the animals reach 100 kg.Conclusion. Thus, the sex of the animal, multipleness, liveborn or stillborn piglets in the litter - all this affected the middle weight at the birth of piglets, as well as the thickness of the scraping and the number of days to achieve live weight 100 kg. Analyzing the above data, we can assume that the ratio rate (weight of the birth of piglets) must be considered to further predict the productivity of the animal.

Effects of drying and providing supplemental oxygen to piglets at birth on rectal temperature over the first 24 h after birth.

Neonatal piglets can experience both a decrease in body temperature and hypoxia, increasing risks for pre-weaning mortality. This research evaluated the effects of drying and providing supplemental oxygen to newborn piglets on rectal temperature (RT) over the first 24 h after birth. The study used a CRD with three Intervention Treatments (IT; applied at birth): Control (no intervention), Drying (dried using a desiccant), Oxygen [dried using a desiccant and placed in a chamber (at 40% oxygen concentration) for 20 min]. A total of 42 litters (485 piglets) were randomly allotted to treatments at the start of farrowing. At birth, each piglet was given a numbered ear tag, weighed, and the treatment was applied; RT was measured at 0, 20, 30, 45, 60, 120, and 1440 min after birth. Blood was collected from one piglet from each birth weight quartile within each litter at 24 h after birth to measure plasma immunocrit concentration. There was no effect (P > 0.05) of IT on piglet RT at 0 or 1440 min after birth. Between 20 and 60 min after birth, piglet RT was lower (P ≤ 0.05) for the Control than the Drying treatment, with the Oxygen treatment being intermediate and different (P ≤ 0.05) from the other two IT. The effect of piglet birth weight on responses to IT were evaluated by classifying piglets into Birth Weight Categories (BWC): Light (<1.0 kg), Medium (1.0 to 1.5 kg), or Heavy (>1.5 kg). There were IT by BWC interactions (P ≤ 0.05) for piglet RT at all measurement times between 20 and 120 min after birth. Relative to the Control, the effects of the Drying and Oxygen treatments on RT were greater (P ≤ 0.05) for Light than heavier piglets. Plasma immunocrit concentrations tended (P = 0.07) to be greater for piglets on the Control treatment compared to the other two IT and were lower (P ≤ 0.05) for Light than Heavy piglets, with Medium piglets being intermediate and different (P ≤ 0.05) to the other BWC. In conclusion, drying piglets at birth reduced the extent and duration of RT decline in piglets in the early postnatal period compared to undried piglets, especially for those of low birth weight. However, the combination of drying and placing piglets in an oxygen-rich environment provided no additional benefit over drying alone.

Exploratory field study on the effects of porcine circovirus 2 (PCV-2) sow vaccination at different physiological stages mimicking blanket vaccination

BackgroundThe objective of the present study was to explore the benefits of Porcine circovirus 2 (PCV-2) blanket vaccination in a sow herd on productive parameters, PCV-2 infection and immune status in sows and their progeny. For this purpose, 288 sows were distributed among four balanced experimental groups. One group remained as negative control group and the other three received 1 mL of PCV-2 Ingelvac Circoflex® intramuscularly at different productive cycle moments: before mating, mid gestation (42–49 days post-insemination) or late gestation (86–93 days post-insemination); phosphate buffered saline (PBS) was used as negative control item. Reproductive parameters from sows during gestation and body weight of their progeny from birth to weaning were recorded. Additionally, blood was collected from sows at each vaccination time and piglets at 3 weeks of age. Moreover, up to 4 placental umbilical cords (PUC) per sow were taken at peri-partum. Sera from sows and piglets were analysed for PCV-2 antibody detection using an enzyme-linked immunosorbent assay (ELISA). Sera from sows and PUC were tested to quantify viraemia using a real time quantitative polymerase chain reaction (qPCR) assay.ResultsGlobally, results indicated that vaccinated sows showed heavier piglets at birth and at weaning, less cross-fostered piglets, lower viral load at farrowing as well as in PUC, and higher antibody levels at farrowing, compared to non-vaccinated ones. When all groups were compared among them, sows vaccinated at mid or late gestation had heavier piglets at birth than non-vaccinated sows, and lower proportion of PCV-2 positive PUC. Also, cross-fostering was less frequently practiced in sows vaccinated at pre-mating or mid gestation compared to non-vaccinated ones.ConclusionsIn conclusion, the present study points out that PCV-2 sow vaccination at different time points of their physiological status (mimicking blanket vaccination) offers benefits at production and serological and virological levels.

Group dynamics in a spontaneously established group of newly weaned piglets

The weaning process poses considerable challenge in pig production. The standard procedure usually involves mixing multiple litters in a relatively dense group where the pigs do not have much space and opportunity to interact uninterruptedly and therefore cannot exhibit the full natural display of agonistic behaviour to establish a hierarchy. Understanding the newly-formed group dynamics in this way is hardly possible under standard weaning procedures. Therefore, we implemented a weaning approach that allowed piglets to mix spontaneously and willingly – each litter was weaned in its pen, separated with an empty pen, with all pens connected by narrow passages that were opened 24 h after weaning. Twelve litters (117 piglets) were included in the study. A total of 2792 fights and 1567 mounts were recorded during the 8-day study period. Fighting was the predominant interaction between litters, most frequent at the beginning of mixing. We found no territorial tendencies in the interactions, except for a lower probability of winning the fight in the piglet’s pen of origin. Heavier piglets were involved in fighting to a significantly greater extent immediately (first day) after mixing, while there were no differences in the frequency of fights regarding body weight later on. However, the probability of initiating a fight increased with body weight, and usually, the initiator was also the winner. On the other hand, mounting was the activity initiated and performed mainly by the piglets of medium body weight. In general, females were more involved in both fighting and mounting. These two interactions showed clear opposing temporal dynamics, with the frequency of fighting steadily decreasing over time, while mounting increased and surpassed fighting in relative occurrence. Thus, the formation of the new dominance hierarchy appears to be a two-phase process: an early phase of high aggression, followed by a phase of low aggression in which mounting replaces fighting. Mounting appeared to serve as a means of mutually determining strength in order to avoid fighting; thus, it plays an important role when the relative strengths of group members are known from previous confrontations. Therefore, in assessing the establishment of social structure, we should not neglect subtle agonistic behaviours (e.g., mounting) that serve as a means of establishing or reinforcing social positions within a group.

Effect of within-litter birth weight variation after cross-fostering on piglet preweaning growth and mortality.

Cross-fostering is commonly used in commercial swine production to equalize litter sizes and/or adjust piglet birth weights within litters. However, there is limited published information on optimum cross-fostering procedures. This study evaluated the effects of within-litter birth weight variation after cross-fostering (using litters of 14 piglets) on piglet preweaning mortality (PWM) and weaning weight (WW). An RCBD was used (blocking factors were day of farrowing and sow parity, body condition score, and functional teat number) with an incomplete factorial arrangement of the following two treatments: 1) birth weight category (BWC): light (<1.0 kg), medium (1.0 to 1.5 kg), or heavy (1.5 to 2.0 kg); 2) litter composition: uniform, all piglets in the litter of the same BWC [uniform light (14 light piglets); uniform medium (14 medium piglets); uniform heavy (14 heavy piglets)]; mixed, piglets in the litter of two or more BWC [L+M (seven light and seven medium piglets); M+H (seven medium and seven heavy piglets); L+M+H (three light, six medium, and five heavy piglets)]. Piglets were weighed at 24 h after birth and randomly allotted to litter composition treatment from within BWC; all piglets were cross-fostered. There were 47 blocks of six litters (total 282 litters and 3,948 piglets). Weaning weights were collected at 18.7 ± 0.64 d of age; all PWM was recorded. Individual piglet WW and PWM data were analyzed using PROC MIXED and PROC GLIMMIX of SAS, respectively; models included fixed effects of BWC, litter composition, and the interaction, and random effects of sow within the block. There was litter composition by BWC interactions (P ≤ 0.05) for WW and PWM. Within each BWC, WW generally increased and PWM generally decreased as littermate weight decreased. For example, WW was greatest (P ≤ 0.05) for light piglets in uniform light litters, for medium piglets in L+M litters, and for heavy piglets in L+M+H litters. Preweaning mortality was lowest (P ≤ 0.05) for medium piglets in L+M litters, and for heavy piglets in L+M+H litters; however, litter composition had no effect (P > 0.05) on PWM of light piglets. In conclusion, increasing the average birth weight of littermates after cross-fostering generally decreased WW and increased PWM for piglets of all birth weight categories. This implies that the optimum approach to cross-fostering that maximizes piglet preweaning growth and survival is likely to vary depending on the birth weight distribution of the population.

Influence of biological and management factors on piglets in the maternity phase

Abstract The goal of this study was to assess the effects of uniformization management, birth order (BO), birth weight (BiW) and their interactions on the performance of piglets in the maternity phase. Sows (n = 25) and their litters (n = 388 piglets) were distributed into two treatments, namely: UNIF - uniformization of piglets between different litters right after birth; and BIOM - piglets kept up to 12 hours after birth with their biological mothers. In both treatments, the effect of BO was assessed in three groups characterised by BO of 1-6, 7-12, and ≥13. The effect of BiW was assessed in four groups defined as ‘very light’, ‘light’, ‘medium’, and ‘heavy’. The design was completely randomised in a 2×3×4 factorial scheme, totalling 24 treatments with 16 piglets/treatment, on average. Weight gain from birth to 72 hours after birth (WG72h) was greater in the BIOM treatment. The colostrum intake (CI) was lower in piglets with BO ≥13. In general, piglet performance increased in response to the increase in BiW. There was interaction between uniformization management and BiW with respect to CI related to body weight (CIBW), which was greater in very light piglets in the UNIF treatment (27.48% BW), and lower in heavy piglets in the BIOM treatment (16.82% BW). It was possible to obtain satisfactory piglet performance by keeping the litters with their biological mothers until 12 hours after birth. The CI expressed on an absolute basis (g) was greater; however, CI expressed on relative basis with respect to body weight (% BW) was lower in heavy piglets.

Effect of rearing cross-fostered piglets in litters of either uniform or mixed birth weights on preweaning growth and mortality.

Cross-fostering is a practice commonly used in the swine industry to equalize litter sizes, however, there is limited understanding of the optimum cross-fostering methods that will maximize piglet preweaning growth and survival. This study evaluated the effects of within-litter variation in birth weight after cross-fostering on piglet preweaning mortality (PWM) and weaning weight (WW) using litters of 15 piglets. A hierarchical incomplete block design was used (blocking factors: day of farrowing and sow parity, body condition score, and number of functional teats) with a 3 × 2 factorial arrangement of treatments: 1) Birth Weight Category (BWC): Light (<1.0 kg), Medium (1.0 to 1.5 kg), or Heavy (1.5 to 2.0 kg); 2) Litter Composition: UNIFORM (all 15 piglets in each litter of the same BWC), or MIXED (five piglets in each litter from each BWC, i.e., five Light, five Medium, and five Heavy piglets). At 24 h after birth, piglets were weighed and randomly allotted to litter composition treatments from within BWC. The experimental unit was five piglets of the same BWC; there were three experimental units within each Litter Composition treatment litter. There were 17 blocks, each of six litters (one UNIFORM litter of each BWC; three MIXED litters) and 51 replicates (three replicates per block of six litters) for a total of 102 cross-fostered litters and 1,530 piglets. Piglets were weaned at 19.7 ± 0.46 d of age; WW and PWM were measured. PROC GLIMMIX and MIXED of SAS were used to analyze PWM and WW, respectively. Models included BWC, Litter Composition, the interaction, and replicate within the block. There were BWC by Litter Composition treatment interactions (P ≤ 0.05) for PWM and WW. Preweaning mortality was greater (P ≤ 0.05) for Light piglets in MIXED than UNIFORM litters. In contrast, for Heavy piglets, PWM was greater (P ≤ 0.05) and WW was lower (P ≤ 0.05) in UNIFORM than MIXED litters. Medium piglets had similar (P > 0.05) PWM and WW in UNIFORM and MIXED litters. The results of this study, which involved large litter sizes typical of current commercial production, suggested that for piglet survival to weaning, using cross-fostering to form litters of piglets of similar birth weight was beneficial for light piglets, detrimental for heavy piglets, and neutral for medium piglets.

84 Effect of rearing cross-fostered piglets in litters of either uniform or mixed birth weights on pre-weaning performance

Abstract There is limited understanding of optimum cross-fostering methods to use to maximize piglet performance. This study evaluated effects of within-litter birth weight variation after cross-fostering on pre-weaning piglet removals (PR; morbidity and mortality) and ADG. A hierarchical incomplete block design was used (blocking factors day of farrowing and sow parity and structure) with a 3x2 factorial arrangement of treatments: 1) Birth Weight Category (BWC): Light (&amp;lt; 1.0 kg), Medium (1.0-1.5 kg), or Heavy (1.5-2.0 kg); 2) Litter Composition (LC): Uniform (piglets of the same BWC), and Mixed (equal numbers of piglets from each BWC). Piglets were weighed 24 h after birth and allotted to form litters of 15 cross-fostered piglets. The experimental unit was 5 piglets of the same BWC (3 experimental units per litter). A total of 102 litters were allotted to 17 blocks of 6 litters (1 Uniform litter of each BWC; 3 Mixed litters) with 51 replicates (3 replicates/block of 6 litters). Weaning weights and PR were measured. PROC GLIMMIX and MIXED of SAS were used to analyze PR and other data, respectively. Models included BWC, LC, the interaction, and replicate within block. There were treatment interactions (P &amp;lt; 0.05) for all measures except birth weight. There was no effect (P &amp;gt; 0.05) of LC on weaning weight or ADG for Light or Medium piglets; Heavy piglets had greater (P &amp;lt; 0.05) weaning weight and ADG in Mixed than in Uniform litters. PR were greater (P &amp;lt; 0.05) for Light piglets in Mixed than in Uniform litters, and for Heavy piglets in Uniform than in Mixed litters. PR for Medium piglets were similar (P &amp;gt; 0.05) across LC treatments. In conclusion, rearing cross-fostered piglets in Uniform litters reduced PR for Light piglets, but increased PR and reduced ADG of Heavy piglets, with no effect for Medium piglets.

PSIX-19 The impact of piglet nursing location along the sow udder line on piglet gain and subsequent weaning weight

Abstract Piglet weaning weight is a critical factor that influences post-weaning growth and performance. Weaning weight is a function of birth weight and the amount and nutrient density of the milk consumed during lactation. Milk production is influenced by sow mammary gland development and diet consumption but may also be a biological function of teat location along the udder line. The objective of this study was then to determine the effects of piglet nursing location along the udder on overall piglet gain and weaning weight. A total of 1,078 individual piglets were observed during the nursing period at three time points during lactation. The teat pairs along the udder line were labeled from anterior to posterior (1-7, respectively) to define nursing location. At the end of the lactation period, the observed piglet nursing location was evaluated for both actual weaning weight and overall piglet weight gain during lactation. Data were evaluated by analysis of variance with the statistical model utilizing litter size as a covariate. As expected, when litter size was utilized as a covariate, there was a significant effect on piglet weaning weight (P &amp;lt; 0.0001), and there was both a linear and quadratic effect of location (L, P &amp;lt; 0.0001; Q, P = 0.0009) on both weaning weight and lactation piglet gain. Heavier piglets were weaned from more anterior teats (teat pairs 1-4), with the numerically heaviest piglets weaned from teat pair 4 (6.12 kg), with the lowest weight piglets being weaned from teat pair 7 (5.17 kg). Piglet weight gain during lactation was impacted by litter size (P &amp;lt; 0.0001), but nursing location did not affect lactation weight gain (P = 0.57). Due to the differences in piglet weights at weaning, it can be concluded that piglet nursing location influences overall piglet weaning weight.

270 Efficacy of Bacillus subtilis and Bacillus licheniformis (BioPlus2B®) on sow lactation performance, litter growth, nursery performance and health of pigs challenged with PRRS virus post-wean

Abstract Probiotics have been shown to support normal growth and immune function in pigs in challenging environments. A commercial probiotic (BioPlus2B®) containing two microbial species (Bacillus subtilis and Bacillus licheniformis) was tested to determine its effect on lactation of sows, pre-weaning performance of litters, and post-weaning performance of pigs challenged with PRRS virus. Sows (n = 120) were fed to meet or exceed NRC 2018 requirements and divided into two treatment groups: control and BioPlus2B®. BioPlus2B® was fed daily at an equivalent of 1.6 x 109CFU/kg and daily feed intake was recorded. Production practices were closely monitored in order to reduce the risk of bacteria cross-contamination between treatment groups and to maintain responsible animal welfare practices. By 24 hours post-farrow, piglets were cross-fostered within treatment group and subsequently weighed. They were weighed again on day 17. Upon weaning at approximately 21 days, piglets from each treatment group were separated into one of three BSL2 rooms and allocated to one of 36 pens per treatment for a 28-day growth study. The treatment group was fed BioPlus2B® daily at 1.1 x 109CFU/kg. At seven days post-wean, pigs were infected IM with 2 x 103.5 TCID 50 of the PRRS virus. Sow, litter, or pen was considered the experimental unit except for birth and wean weights. Sows that consumed BioPlus2B® daily birthed heavier piglets, consumed more feed throughout lactation, and tended to wean heavier pigs than Control sows. Pigs that consumed BioPlus2B® post-wean resulted in greater ADG, ADG:ADFI, and reduced mortality after PRRS infection. Data is expressed as least square means ±SEM. Values at P&amp;lt; 0.05 are considered significantly different while values between 0.05&amp;lt; P≤0.10 are considered a trend. In summary, feeding a defined probiotic supports optimal performance of sows and litters and effective immune responses of pigs challenged with respiratory disease.