Induction of parturition by double administration of prostaglandin F2α in sows reduces the variation of gestation length without affecting the colostrum yield and piglet performance

Colostrum intake and neonatal characteristics in piglets experiencing varying lengths of expulsion phase

The objective of this study was to investigate how the cumulative expulsion interval, litter size, and birth order influence the characteristics of newborn piglets from hyperprolific sows, as well as their intake of colostrum. Analysis was conducted on the temporal aspects of parturition in 254 sows, including 3920 piglets. Newborn piglet characteristics examined encompassed delivery time, birth order, birth status, umbilical cord rupture, meconium staining, delivery ease, birth weight, blood oxygen saturation, and heart rate. From the raw data, colostrum intake, birth interval, and cumulative birth interval of each piglet were computed. Piglets were sorted based on the cumulative expulsion interval into nine categories: 0-30, 31-60, 61-90, 91-120, 121-150, 151-180, 181-210, 211-240, and >240 min. Litter sizes were categorized into three groups: 10-13, 14-17, and ≥18 piglets per litter. The birth-order ranking referred to the piglet's position within a litter and was categorized into four quartiles: 1, 2, 3, and 4. On average, the expulsion interval, cumulative expulsion interval, and colostrum consumption were 14.8 ± 21.8 min, 138.6 ± 155.7 min, and 407.6 ± 162.1 g, respectively. In litters with ≥18 piglets, the percentage of piglets with inadequate colostrum intake (<300 g) was higher compared to litters with 10-13 piglets (33.1 % vs. 12.9 %, P < 0.001) and 14-17 piglets (23.9 %, P < 0.001). The occurrence of stillbirths in the fourth quartile of the litter was higher than in the first (16.0 % vs. 2.2 %, P < 0.001), second (4.0 %, P < 0.001), and third (7.8 %, P < 0.001) quartiles. Among litters with ≥18 piglets, those born in the third quartile exhibited lower colostrum consumption compared to those born in the first quartile (346.0 ± 9.9 vs. 391.4 ± 8.6 g, P = 0.028). Colostrum intake decreased with longer cumulative expulsion intervals, evident from a notable decline starting at 90 min post-farrowing compared to piglets born within the first 30 min (P = 0.004). Interestingly, colostrum consumption exhibited a negative correlation with the cumulative expulsion interval (P < 0.001), but not with individual piglet expulsion intervals (P = 0.460). Piglets born with meconium staining were most prevalent among those with a cumulative expulsion interval of >240 min. In summary, both the cumulative expulsion interval and birth-order ranking significantly impact the physiological characteristics of newborn piglets and their colostrum intake. Colostrum consumption decreases and newborn piglet characteristics change with higher cumulative expulsion intervals. Identifying piglets at high risk of hypoxia and implementing appropriate treatments and management strategies within an optimal timeframe could aid pig producers in reducing pre-weaning mortality among piglets born to hyperprolific sows.

INDUCTION OF PARTURITION IN A PYGMY HIPPOPOTAMUS (CHOEROPSIS LIBERIENSIS)

A 27-yr-old female pygmy hippopotamus (Choeropsis liberiensis) had two consecutive stillbirths with no overt signs of labor, suggestive of uterine inertia. After a third pregnancy was confirmed, an induction protocol was developed. Cloprostenol and betamethasone were administered on d 200 of gestation (time 0 h). Additional doses of cloprostenol were administered at 24 and 48 h and oxytocin at 30, 31, and 48 h. Each injection resulted in preparturient behavior without overt evidence of contractions. Fetal membranes presented at the vulva at 54.5 h after initial cloprostenol and betamethasone administration with no progression of labor. Transvaginal palpation and manual delivery of a live calf followed. Despite confirmed nursing, the serum glutaraldehyde coagulation test was negative. Failure of passive transfer may have been secondary to the induction protocol. The calf was treated with broad-spectrum antimicrobial agents due to diarrhea, and clinical signs resolved. This clinical brief details the first known induction of parturition in a pygmy hippopotamus, which can serve as the basis for further development of the technique.

Impacts of supplementing Cannabis sativa byproducts during the transition period on behaviour, feed consumption, constipation levels, colostrum production and piglet performance in hyperprolific sows

In the modern swine industry, inflammation and pain in sows after farrowing represent a crucial animal welfare concern. Cannabis sativa, a medicinal plant, has analgesic, anti-inflammatory and antipyretic properties and is rich in fibre. The objective of this study is to examine the impacts of supplementing sows with Cannabis sativa byproducts during transition periods (7 days before and after farrowing) on various aspects including postpartum behaviour, feed intake, constipation, farrowing duration, colostrum yield and piglet performance. The experiment involved a total of 100 Landrace × Yorkshire sows. The sows were distributed according to parity numbers into two groups, i.e., control (n = 54) and treatment (n = 46). The control group was provided with a lactation diet at 3.0-3.5 kg per day for a period of 7 days before and after farrowing. The treatment groups received the same quantity of the diet but with an additional supplementation of 150 g/d of Cannabis sativa byproduct. The byproduct was analysed and contained 0.24 % (w/w) cannabidiol (CBD), resulting in a daily intake of 360 mg of CBD per sow. The conventional lactational diet had a dietary fibre content of 4.3 %, whereas the diet supplemented with Cannabis sativa byproduct had a higher dietary fibre content of 16.9 %. Video cameras were used to observe and document the behaviour of sows within the initial 24 h after farrowing. The duration in which sows engaged in activities such as sleeping, sitting, standing, feeding and nursing their piglets was quantified. Additionally, the rectal temperature of the sows was measured, and a temperature equal to or exceeding 39.5 °C was considered indicative of fever. The faecal score of the sows was assessed, and a faecal score of ≤2 was classified as constipation. On the third day postpartum, the proportion of sows with fever in the treatment group was lower than that in the control group (20.0 % and 38.9 % respectively, P = 0.051). Sows receiving supplementation with Cannabis sativa byproducts exhibited increased durations of standing and feeding compared to those in the control group (P < 0.05). Notably, overall, sows without constipation issues spent more time consuming feed than those experiencing constipation (P = 0.006). The prevalence of constipation was significantly lower in the treatment group compared to the control group (17.4 % and 81.5 %, respectively, P < 0.001). Furthermore, the postpartum sows demonstrated increased feed intake following supplementation with Cannabis sativa byproducts (P < 0.05). Sow colostrum yield, piglet colostrum intake, piglet mortality and other piglet traits did not differ between the control and treatment groups (P > 0.05). In conclusion, supplementing Cannabis sativa byproducts during the transition periods in peri-parturient sows under tropical conditions resulted in a reduction in constipation issues and improved sow activities, such as increased time spent standing and consuming feed within the first 24 h postpartum.

Cloprostenol sodium improves reproductive performance of multiparous sows during lactation

This study aimed to determine the effect of prostaglandin F2α (PGF2α) analog (D-cloprostenol sodium and DL-cloprostenol sodium) administration on the milk yield of multiparous sows (MS) and piglet growth performance. In total, 320 Landrace×Yorkshire parturient MS were randomly divided into three groups on day 115 of pregnancy: without treatment (N = 50), with 75 μg D-cloprostenol sodium (N = 137), and with 200 μg DL-cloprostenol sodium (N = 133). After delivery, the sows treated with D-cloprostenol sodium and DL-cloprostenol sodium were randomly allocated into three subgroups, respectively: (i) no additional treatment after farrowing; (ii) administration of cloprostenol sodium at 3 h and 5 days after farrowing; and (iii) administration of cloprostenol sodium at 3 h, 5 days, and 10 days after farrowing. Cloprostenol sodium effectively induced sows to synchronize parturition approximately 23 h after administration and increased the daytime delivery rates (p < 0.05). Compared with DL-cloprostenol sodium, D-cloprostenol sodium shortened the farrowing duration and birth interval of sows for inducing farrowing (p < 0.05). Moreover, we observed that a single administration of both D-cloprostenol sodium and DL-cloprostenol sodium a day before delivery significantly reduced the rates of stillborn piglets type II in MS (p < 0.05). Compared to no treatment and single treatment with cloprostenol sodium, quartic treatments with cloprostenol sodium significantly increased the daily feed intake of MS, litter weight after weaning, and average daily gain of piglets (p < 0.05). Cloprostenol sodium improved the 21-day milk yield, with D-cloprostenol sodium showing the best effect, which increased lactation ability by 30.30% (176.72 kg vs. 135.63 kg) (p < 0.05). DL-cloprostenol sodium followed closely, increasing lactation ability by approximately 25.00% (169.71 kg vs. 135.63 kg) (p < 0.05). During lactation, sows administered with D-cloprostenol sodium observed increased serum prolactin levels. Compared to untreated sows, the sows administered with D-cloprostenol sodium and multiple DL-cloprostenol sodium visibly shortened the weaning-to-estrus interval (WEI) and weaning-to-service interval (WSI) (p < 0.05). Furthermore, quartic injections of D-cloprostenol sodium resulted in an 18 percentage point increase in the pregnancy rate of breeding sows compared to controls (82.61% vs. 64.58%) (p > 0.05). In summary, cloprostenol sodium could enhance the reproductive performance of MS, particularly in terms of lactation performance. Additionally, the effect of quartic injections of D-cloprostenol sodium was the most pronounced.

Factors associated with farrowing assistance in hyperprolific sows

OBJECTIVE

The present study was performed to determine risk factors associated with the frequency of farrowing assistance in hyperprolific sows in a tropical environment and to investigate the impacts of farrowing assistance on piglet colostrum consumption and sow colostrum yield.

METHODS

Farrowing data from 352 Landrace×Yorkshire crossbred sows and 5,554 piglets in five commercial swine herds in Thailand were investigated. The sows were classified according to parity numbers: 1 (n = 72), 2 to 4 (n = 128), 5 to 6 (n = 84), and ≥7 (n = 68) and the total number of piglets born per litter (TB): 10 to 13 (n = 90), 14 to 16 (n = 117), and ≥17 (n = 145). The incidence of farrowing assistance and associated parameters were investigated.

RESULTS

The TB and farrowing duration averaged 15.8±0.2 and 279.9±11.2 min, respectively. The percentage of sows that required farrowing assistance was 29.8% and varied among herds from 5.7% to 53.3% (p<0.001). The percentage of piglets born after birth assistance using manual intervention was 8.4%. Sows with parity numbers 1 and 2 to 4 had a lower frequency of farrowing assistance than sows with parity numbers ≥7 (p<0.01). The colostrum yield of sows that required farrowing assistance did not differ from sows that farrowed without assistance (5.3±0.2 and 5.1±0.1 kg; p = 0.288); however, the colostrum consumption of piglets born from sows that required farrowing assistance was lower than those born from sows that farrowed without assistance (302.2±15.7 and 354.2±5.6 g; p<0.001). Blood oxygen saturation of the piglets born after birth assistance tended to be lower than the piglets that farrowed without birth assistance (87.8%±1.3% vs 90.4%±0.4%; p = 0.054).

CONCLUSION

The frequency of farrowing assistance in sows varied among herds and was influenced by parity number. The piglets born after receiving birth assistance should receive special care to improve their blood oxygen saturation and enhance colostrum intake.

Effect of a combination of altrenogest and double PGF2α administrations on farrowing variation, piglet performance and colostrum IgG

The variation of gestation length in sows leads to difficulties performing farrowing supervision. The present study was performed to investigate whether oral administration of altrenogest until 112 days of gestation and double administration of PGF2α at 113 days of gestation can synchronise the onset of parturition in sows and minimise deleterious effects on the incidence of stillbirths and colostrum quality. Additionally, the effects of synchronised farrowing on colostrum yield and piglet birth weight, colostrum intake and survival rate of piglets until seven days of postnatal life were also investigated. In total, 193 Landrace x Yorkshire crossbred sows were randomly allocated according to parity number into two groups, i.e. control (n = 95) and treatment (n = 98). The control sows were allowed to farrow naturally. The treatment sows were orally administered 20 mg per day of altrenogest for four days from 109 to 112 days of gestation and were administered PGF2α twice on day 113 of gestation. Individual body weight at birth and 24 h after birth of piglets in all litters were determined in both control (n = 1609) and treatment (n = 1707) groups. Colostrum consumption of all piglets, colostrum yield, colostrum IgG and serum progesterone of sows were determined. On average, the total number of piglets born per litter were 17.0 ± 3.1. The proportion of sows farrowed before 114 days of gestation was higher in the control than the treatment group (8.4% and 2.0%, respectively, P = 0.05) and 92.8% of sows in the treatment group farrowed on day 114 of gestation. The percentage of stillborn piglets per litter did not differ significantly between control and treatment groups (4.5% and 4.6%, respectively). Colostrum yield of sows did not differ between control and treatment groups (5.52 ± 0.13 and 5.28 ± 0.12 kg, respectively, P = 0.174). However, colostrum intake of piglets was lower in the treatment than the control group (354.7 ± 6.6 and 381.2 ± 7.0 g, respectively, P = 0.012). Colostrum IgG was higher in the control than the treatment group (41.2 ± 1.1 and 37.3 mg per ml, P = 0.013). In conclusion, altrenogest treatment from 109 to 112 days and double administrations of PGF2α on day 113 of gestation can control gestation length in sows. No deleterious effects of this protocol on the incidence of stillbirths and sow colostrum yield were detected. However, piglet colostrum intake and colostrum IgG were compromised. Thus, care of newborn piglets in the treatment group should be considered.

Effects of farrowing induction using cloprostenol on sow farrowing characteristics

Background and Aim: Previous findings regarding the effects of farrowing induction on the farrowing characteristics of sows are controversial. This study aimed to investigate the effects of farrowing induction on the following characteristics: (1) Proportion of sows that farrowed during working hours, (2) stillbirth rate, (3) number of stillbirths per farrow, (4) dystocia rate per farrow, (5) dystocia rate (the proportion of farrowings that had at least one dystocia event), (6) number of dystocia events per farrow, (6) farrowing duration, (7) birth interval, and (8) birth weight. Materials and Methods: Thirty-eight Landrace x Yorkshire sows were randomly allocated into two groups; the control group and the treatment group. In the control group (n = 18), sows farrowed spontaneously. In the treatment group (n = 20), farrowing was induced approximately 2 days earlier than the herd's average length of gestation (7:00 am on day 114) by injecting cloprostenol into the perivulval region. All sows were supervised throughout their farrowing. We recorded the interval between induction and farrowing; total number of births; number of live, stillborn, and mummified piglet births; number of dystocia events; birth interval; farrowing duration; and birth weight. A generalized linear mixed model, a linear mixed-effects model, the Chi-squared test, and Student's t-test were used to compare outcomes between the two groups. Results: Farrowing induction did not influence the percentage of sows that farrowed during working hours (7 am–5 pm), stillbirth rate, birth weight, and number of dystocia events per farrow. Farrowing induction led to an increase in birth interval, dystocia rate, dystocia per farrow (p < 0.05) and in addition to the percentage of sows that farrowed on the day following induction (60% vs. 27.8%; p < 0.05). Conclusion: Farrowing induction using a single dose of cloprostenol 2 days before the expected farrowing date can be performed with care to concentrate farrowing into a short interval. This can enhance the optimization of cross-fostering and the practice of an all-in-all-out strategy in the swine breeding industry.

Incidence of dystocia at piglet level in cloprostenol-induced farrowings and associated risk factors

Few studies have investigated risk factors for dystocia in swine, although this birthing abnormality can compromise welfare of both sows and piglets by increasing stillbirth rate and decreasing sow productivity. This study aimed to determine risk factors associated with dystocia at piglet level in cloprostenol-induced farrowings. A dystocia event was recorded when a birth interval exceeded 45 min or when manual extraction was applied. Data were collected from 898 piglets born from 77 Landrace × Yorkshire crossbred sows, which were induced for farrowing on day 114 of gestation. Generalized linear mixed models (GLMMs) were used to evaluate the association between dystocia and parity, gestation length, litter size, relative birth order (RBO (%) = 100 ⋅ birth order/litter size), birth weight, crown rump length, body mass index, ponderal index, piglet's sex, use of oxytocin, and stillbirth. Sows nested in farrowing batches were fitted as random factors in GLMMs. Incidence of dystocia at piglet and farrowing levels was 11.0 % and 75.3 %, respectively. The final multivariate model explained 20.1 % variation of dystocia. RBO had a quadratic effect on dystocia in which incidence of dystocia decreased from RBO ≤ 40 % to RBO = 60 %–70 %, and then increased to the end of parturition. Piglets with birth weight > 1700 g and stillborn piglets had higher odds of dystocia in comparison with piglets with a birth weight of 900–1700 g (OR = 2.63; 95 % CI = 1.66–4.18) and live-born piglets (OR = 2.62; 95 % CI = 1.12–6.15), respectively. This study indicates that dystocia is very common in cloprostenol-induced farrowings and suggests that the last one-third of parturitions is the most important stage to be supervised, and selection for homogenous litters and moderate high birth weight may reduce the rate of dystocia.

Development of a Novel Vaginal Drug Delivery System to Control Time of Farrowing and Allow Supervision of Piglet Delivery

The swine industry has evolved significantly in the recent decades, but this has come at considerable expense to piglet survival. Breeding sows for greater prolificacy has been accompanied by a greater proportion of piglets being born underweight, of lower vigor, and higher susceptibility to early mortality. Inducing sows to farrow during working hours has the potential to increase piglet survivability, but non-therapeutic injectable products are often discouraged on farms. We aimed to design and develop a novel vaginal drug delivery system (NVDDS) that could reliably trigger luteolysis and induce parturition. To achieve this, two vaginal tablets containing the luteolytic agent cloprostenol were formulated to be inserted together: one would release constituents immediately on insertion (immediate release; IR) and the other would release cloprostenol in a controlled manner (controlled release; CR). The two formulations (IR and CR) were evaluated for drug release, swelling and bio-adhesion in conditions simulating the sow vaginal environment. The IR tablet released the drug completely for 5 min whereas the CR tablet took 5 h to release 50% of the drug. Furthermore, the release kinetics were evaluated by fitting the dissolution profiles into different mathematical models. Both IR and CR tablets were best fitted by the Makoid–Banakar model which assumes release by summation of different mechanisms. The performance of the optimized formulations was studied in vivo with 161 Large White x Landrace sows of varying parity (0–5). The sows were assigned to five groups. Group 1 (SI) received a single vulval injection of cloprostenol at 0700 h (n = 32), group 2 (SDI) received the same dose split in two parts, at 0700h and 1300h (n = 33). Group 3 (IRT) animals were administered an IR tablet at 0700h (n = 32), while group 4 (IRCRT) received both IR and CR tablets at 0700 h (n = 33). Group 5 was untreated and served as a control (n = 32). The interval to farrowing was longer (p < 0.001) for controls than for treated sows, but there were no differences among cloprostenol treatments for timing of farrowing. The finding confirms the efficacy of the NVDDS for induction of farrowing in sows.

Effects of farrowing induction with prostaglandins on farrowing traits and piglet performance: A systematic review and meta-analysis

Induction of farrowing with prostaglandins is a way of increasing farrowing supervision and to provide adequate care for piglets in the first hours of life. However, some studies observed negative effects associated with induction, including decreased piglet viability, reduced birth weight and decreased colostrum yield. Furthermore, the farrowing response of sows to prostaglandins treatment varies among studies, largely influenced by the induction protocol applied. Thus, a systematic review and meta-analysis was carried out to evaluate the effects of farrowing induction with prostaglandins on stillbirth rate, birth weight, pre-weaning mortality, weaning weight, farrowing duration and colostrum and milk characteristics as well as the farrowing response to prostaglandin treatment. The interval from farrowing induction to onset of farrowing (IFIOF) was 31 h, and a twice application of prostaglandin increased by 37% the proportion of sows farrowing during the next working day. Prostaglandins had no effect on farrowing duration (P > 0.05). Piglet birth weight and weaning weight were only decreased (P < 0.05) when farrowing was induced ≥3 days before the expected farrowing date (based on herd average or in gestational length of the control group). Induction three or two days before the expected farrowing date had no effect on stillbirth rate; conversely, stillbirth rate was reduced by 28% (P < 0.05) when induction was performed one day before the expected farrowing date. Farrowing induction had no influence on pre-weaning mortality. The present study strengthened the observations that farrowing induction with prostaglandins is a valuable tool to reduce gestational length variation and to synchronize farrowing during the working day, allowing better assistance to sows and piglets. To obtain the maximum benefit of farrowing induction, it is recommended that induction should be performed one or two days before the expected farrowing date.

Biochemistry and Immune Biomarkers Indicate Interacting Effects of Pre- and Postnatal Stressors in Pigs across Sexes

The effects of maternal immune activation (MIA) elicited by a prenatal stressor and postnatal metabolic or immune stressors on chemical and inflammatory biomarkers were studied in male and female pigs. Pigs exposed to MIA elicited by porcine reproductive and respiratory syndrome virus and matching controls were assigned at two months of age to fasting stress, immune stress, or a saline group. The serum levels of over 30 chemistry and immune analytes were studied. Significantly low levels of blood urea nitrogen were detected in females exposed to MIA, while the highest creatinine levels were identified in fasting females exposed to MIA. The levels of interferon gamma and interleukin 8 were highest in pigs exposed to postnatal immune challenge. The profiles suggest that MIA may sensitize pigs to postnatal stressors for some indicators while making them more tolerant of other stressors. Effectiveness of practices to ameliorate the impact of postnatal stressors on the physiology of the pig could be enhanced by considering the prenatal stress circumstances.

Postpartum prostaglandin F2α administration affects colostrum yield, immunoglobulin G, and piglet performance

Objective

Current study was conducted to determine the effect of postpartum prostaglandin F2α (PGF2α) administration on colostrum and milk yield, colostrum immunoglobulin G (IgG) and piglet growth performance.

Methods

In total, 36 sows were included in the experiment. The sows were classified into two groups: i) control (n = 11) and ii) PGF2α (n = 25). Sows in the PGF2α group received 10 mg of PGF2α within an hour after farrowing. The body weight of piglets was measured at 0 and 24 h after birth to estimate colostrum consumption. Colostrum was collected at 1 and 24 h after farrowing to determine IgG concentrations. For milk yield study, the remaining sows in the PGF2α group (n = 23) were divided into two subgroups: i) single PGF2α (n = 12) and ii) multiple PGF2α (n = 11). In the multiple PGF2α, the sows received repeated doses of PGF2α at seven and 14 days postpartum. The piglets’ body weight was measured at 0, 1, 5, and 20 days of age. The milk yield of the sows was calculated.

Results

Colostrum yield of sows averaged 5.62±2.25 kg. Sows treated with PGF2α postpartum had a higher colostrum yield than control (7.01 and 5.12 kg, p<0.05). The concentration of IgG in colostrum at 24 h in the PGF2α group was higher than the control (31.6 and 17.4 g/L, p<0.05). For primiparous sows, milk yield was highest in the sows treated with multiple doses of PGF2α during lactation and lowest in control sows (10.25 and 7.61 kg, p<0.05). Colostrum intake was higher in the treatment than the control groups (+56.7 g, p<0.05). Primiparous sows treated with multiple doses of PGF2α had a higher litter weight than controls (p<0.01).

Conclusion

Postpartum treatment with PGF2α improved colostrum yield and IgG in multiparous sows and increased colostrum intake of piglets. Multiple administration of PGF2α improved the milk yield and increased litter weight of piglets in primiparous sows.

Impact of sow parity on yield and composition of colostrum and milk in Danish Landrace × Yorkshire crossbred sows

The present study aims to characterize the colostrum, milk yield and composition and to determine whether sow parity would influence yield and composition of colostrum and milk in Danish Landrace × Yorkshire crossbred sows. The data were collected from sow parity numbers 1 (n = 27), 2-4 (n = 48) and 5-6 (n = 30) from Danish Landrace × Yorkshire crossbred sows reared in a commercial swine herd in Thailand. The piglets were weighed on day 0 (<1 h), 1 (24 h), 3, 10 and 17 after birth to determine the colostrum and milk yields of the sows using a prediction equation. Milk samples were collected manually within 1 h of the onset of parturition and on days 3, 10 and 17 after farrowing to evaluate milk composition. A general linear model procedure was used to analyze the effects of sow parity numbers on colostrum yield and composition and a general linear mixed model procedure was used to analyze the effects of sow parity numbers on yield and composition of milk. The model included the fixed effects of sow parity number and time (day after parturition). The sow parity numbers 2-4 (7.0 kg) had a higher colostrum yield than 1st parity sows (5.4 kg, P =  0.002) and parity 5-6 sows (5.9 kg, P = 0.025). No evidence of parity differences was observed on milk yield (P = 0.306). No effect of sow parity numbers on fat, protein and lactose in milk was observed. The dry matter in sow parity numbers 2-4 (19.8 g/100 g) had a tendency to be higher than sow parity number 1 (18.6 g/100 g, P =  0.107) and 5-6 (18.4 g/ 100 g, P =  0.053). In conclusion, sow parity number had an impact on colostrum yield in Danish Landrace × Yorkshire crossbred sows in a tropical climate but did not influence colostrum, milk composition and milk yield. Colostrum yield in Danish Landrace × Yorkshire crossbred sows was the highest in sow parity numbers 2-4.