The concern for restricted movement for sows housed in stalls during gestation has prompted the swine industry to move towards group housing. Additionally, the emphasis on increasing sow productivity has led to a continuous need for re-evaluation of nutrient requirements for sows, including minerals. Unfortunately, the majority of studies that examined the role of dietary Ca and P for sows were older (early 1970s to 1990s), and may not be applicable to the modern, prolific sow, particularly those housed in group housing systems. Two studies were conducted to determine the effects of dietary Ca and P for gestating sows on reproductive performance, bone metabolism and fetal skeletal development. The objective of the first study was to determine if the recommended levels of dietary Ca and P are adequate for sows housed in groups, and thus have potential for increased mobility. A total of 180 multiparous sows and gilts were assigned to 1 of 6 treatments. Treatments, arranged as a 3 × 2 factorial, included main effects of dietary Ca:P; 0.70:0.55 (% as fed, Control); 0.60:0.47 (-15 % 1998 NRC); 0.81:0.63 (+ 15 % 1998 NRC) and housing; stalls or groups. Sows were fed 2.3 kg/d from wk 4 to 5 of gestation until 2 wk prior to farrowing when the allotment was increased to 3.0 kg/d. Serum samples were collected at the start of the trial and on d 100 of gestation, and both serum and milk samples were collected at mid-lactation and prior to weaning. Neither diet nor housing had an effect on total number of piglets born, ADG from birth to weaning, or weaning weight (P > 0.10). The number of piglets born live and birth weight were unaffected by diet (P > 0.10) but improved in group housing relative to stalls (P < 0.05). In late gestation, group-housed sows fed the low Ca diet had reduced serum Ca (diet × housing interaction; P = 0.02) and the greatest reduction in serum P level was also observed in group-housed sows fed the low Ca diet (diet × housing interaction; P = 0.04). Osteocalcin (OC), and pyridinoline (PYD) markers of bone formation and resorption respectively, were unaffected by diet or housing (P > 0.10). The second study was conducted to determine the influence of Ca and P intake by young, gestating sows on the growth and skeletal development of their developing piglets and if smaller birth-weight piglets are at greater risk from mineral insufficiency during gestation. A total of 30 sows were randomly assigned to 1 of the 3 dietary Ca:P treatments used in the first study. Sows were fed their daily rations in 1 allotment as described in Exp. 1. Only sows farrowing litters with 12 piglets or more remained on trial. At birth, the smallest and a normal-sized piglet from each litter were euthanized, and the left femur extracted for peripheral quantitative computed tomography (pQCT) scanning. Serum samples were collected at birth and prior to weaning. Number of piglets born, body weight (BW) at 3 d of age, and piglet ADG were unaffected by treatment (P > 0.10). At birth, the highest serum Ca level was seen in the small piglets from sows fed a high Ca diet (diet × size interaction; P = 0.04) however, at weaning, this value had the smallest deviation from the initial value (diet × size interaction; P = 0.02). Femurs of piglets from sows fed the low Ca diet had the highest cortical density (P = 0.03) and piglet size had no effect on cortical density (P > 0.10). Bone ash %, ash Ca %, ash P %, and serum bone markers were unaffected by diet or piglet size (P > 0.10). Results from these studies suggest that the recommended level of dietary Ca and P as prescribed by NRC 1998, and thus for NRC 2012, is adequate for high-producing sows of modern genetics, whether housed in stalls or groups. Moderate changes in Ca and P intake by young, gestating sows, does not negatively affect the growth or skeletal development of their piglets.

Para ser competitivo atualmente, o sistema intensivo de produção de suínos deve estar pautado na eficiência. A fim de obter esta eficiência produtiva, o avanço genético das ultimas décadas buscou por fêmeas suínas cada vez mais prolíficas. A prolificidade contudo, veio acompanhada por uma queda no consumo voluntário de alimento por parte das fêmeas, bem como um aumento na produção de leite, e no número de leitões nascidos; o aumento da leitegada, levou a uma redução do peso ao nascimento e um aumento da heterogeneidade entre os leitões. Como forma de contornar o problema, são oferecidas aos leitões dietas formuladas com ingredientes de alto valor biológico a partir dos sete dias de vida, procurando suprir a demanda nutricional do animal durante o período de amamentação e preparar seu sistema digestório para o desmame. Contudo, grande parte das dietas formuladas para os leitões neonatos são oferecidas aos animais em sua forma sólida. Neste projeto, avaliamos os efeitos sobre a performance de leitões neonatos e da performance reprodutiva da fêmea suína do oferecimento de uma dieta líquida para os leitões neonatos, dieta esta que foi disponibilizada aos animais através de um sistema automatizado que realizou a mistura do alimento em sua forma sólida com a água. Para tais avaliações, os leitões ao nascer foram alocados em três grupos distintos, recebendo a dieta em sua forma líquida, em sua forma sólida ou então apenas o leite materno. Foram avaliadas variáveis zootécnicas relacionadas aos leitões, como peso, ganho diário de peso, consumo de ração, conversão alimentar, mortalidade pré-desmame; frequência de dias com diarreia nos leitões em fase de maternidade e creche. Foram eutanasiados leitões aos 14 e aos 28 dias de idade, para a realização do exame morfométrico da altura de vilosidade, profundidade de cripta e a relação entre a altura de vilosidade e profundidade de cripta nas porções do duodeno, jejuno e íleo. Avaliamos também o impacto do uso da dieta líquida sobre o catabolismo sofrido pela fêmea durante a lactação, através da aferição do peso e da espessura de toucinho desta fêmeas durante o período lactacional e também a duração do intervalo desmame estro e a duração do estro subsequente ao desmame. Não verificamos contudo um melhor desempenho zootécnico dos leitões nos períodos de maternidade e creche, tão pouco uma alteração favorável quanto a frequência de dias com diarreia nas duas fases em relação aos leitões que não consumiram nenhum tipo de suplementação. Quanto aos parâmetros morfométricos do intestino delgado, apenas aos 28 dias de idade os leitões que receberam a dieta líquida apresentaram maiores alturas de vilosidades no íleo em relação aos leitões que consumiram a dieta sólida e os animais do grupo controle apresentaram menores profundidades de cripta no mesmo seguimento e idade quando comparados aos demais animais. Contudo, estas alterações não foram o suficiente para garantir diferenças na relação altura de vilosidade:profundidade de cripta. E ainda, a suplementação independente de sua forma não reduziu o catabolismo sofrido pela fêmea suína durante a lactação / To be competitive today, intensive pig production system must be founded on efficiency. In order to obtain this production efficiency, genetic progress of recent decades sought for sows increasingly prolificity. Prolificity however, was accompanied by a decrease in voluntary feed intake by the sow, an increase in milk yield, and the number of piglets born; increased litter led to a reduction in birth weight and increased heterogeneity among piglets. In order to solve this problem, are offered to piglets diets formulated with high biological value ingredients starting at seven days of life, trying to meet the nutritional demand of the animal during the breastfeeding period and prepare digestive system for weaning. However, most diets formulated for newborns piglets are offered in its solid form. In this project, we evaluated the effects on performance of newborn piglets and reproductive performance of swine female offering a liquid diet for the newborn piglets, which was made available to the animals through an automated system that held the mixture of solid feed with water. For such evaluations, the piglets were divided into three groups, receiving the diet in liquid form ,in its solid form or only breast milk. Husbandry variables related to the piglets were evaluated, such as weight, daily gain, feed intake, feed conversion, pre-weaning mortality; frequency of days with diarrhea in piglets in maternity and nursery. Piglets were euthanized at 14 and 28 days for morphometric examination of villus height, crypt depth and the ratio of villus height and crypt depth in the portions of the duodenum, jejunum and ileum. We also evaluated the impact of the use of liquid diet on the catabolism suffered by the sow during lactation, by measuring the weight and backfat thickness during the lactation period and also the duration of weaning to estrus interval and duration of the subsequent estrus. We not checked a better growth performance of piglets during periods of maternity and nursery, nor a favorable change for the frequency of days with diarrhea in this two phases. As for the morphometric parameters of the small intestine, only 28 days old piglets that received liquid diet showed greater heights of villi in the ileum for piglets that consumed the solid diet and the control group showed lower crypt depth in the same tracking and age when compared to other animals. However, these changes were not enough to warrant differences in villus height:crypt depth. And yet, the independent supplementation of its form not reduced catabolism suffered by female swine during lactation

Porcine Reproductive and Respiratory Syndrome (PRRS) is, globally, one of the costliest of diseases to the pig industry. Despite enormous efforts, methods such as vaccination strategies and herd management have failed to fully control the disease. Exploiting the genetic variation in host response could be included as part of a multifaceted approach to mitigate the devastating impact of this disease. Establishing the presence of genetic variation and its underlying genetic architecture are key to implementing genomic selection, which is considered a viable and safe long-term disease control strategy. This thesis explores the effect of natural PRRSV outbreaks on the reproductive performance of sows, and the underlying genetic influences on it. Litter records were available from two farms, where Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) outbreaks had been confirmed using ELISA. One farm had full pedigree information, but for both farms 60K SNP genotypes were available. In both farms, performance records could be partitioned into an epidemic and non-epidemic phase using a previously established threshold method. The partitioning also identified a period of high reproductive failure not coinciding with a diagnosed PRRSV outbreak on one farm. This period was isolated and analysed separately. Linear mixed models were used to explore both genetic and non-genetic factors contributing to differences in reproductive performance associated with the two phases. This analysis identified five disease indicator traits identified showing significant differences (>95% CI) in least squares means between the epidemic and non-epidemic phase. These were the number of mummified, stillborn, dead and alive piglets per litter and the fraction of the total born dead. Alternative statistical models that accounted for differences in the severity of the individual PRRSV outbreaks were also considered throughout. Despite differences in the estimates associated with different models and farms, in general very low heritability estimates were obtained for these disease indicator traits during the non-epidemic phase, whereas the traits were found moderately heritable during the epidemic phase. Two genome wide association analyses methods were used to explore the distribution of the genetic effects throughout the genome: Family-based Score Test for Association (FASTA) and Genome-wide Rapid Analysis using Mixed Model and Regression (GRAMMAR). In addition, regional associations were studied using Regional Heritability Mapping (RHM). Associations were then further characterised using Measured Genotype (MG) analyses. Genome-wide significant associations were identified for five SNPs and one region. The regional association spans the region previously identified in an experimental challenge experiment of growing pigs, in association with viral load and weight gain. Different patterns of linkage disequilibrium (LD) are observed which may explain why this study and others failed to find single SNP effects at this location. One genome wide significant SNP on SSC15 was found between two previously identified SNPs associated with PRRSV mortality. Five further putative SNP associations are indicated by RHM and subsequent measured genotype analysis, two of which flank previously reported associations and indicate an epistatic effect, observed in several traits. In summary, this study showed that reproductive performance of sow is considerably reduced during PRRSV outbreaks and the genetics of the sow significantly affects variance in survival and mortality. Several novel genomic regions associated with the reproductive performance of sows in the absence and during PRRSV outbreaks have been identified in this study. In addition to these, the results suggest the region on SSC4 previously associated with PRRSV viral load and weight gain may also affect foetal mortality. These results demonstrate the potential for genomic selection to be used to mitigate PRRSV related reproductive losses, the greatest financial exposure faced by the pig industry. In addition, RHM is directly shown to capture genetic variance, where single SNP methods fail to identify an effect, highlighting the usefulness of this tool as a method to identify genomic regions with significant effect on production traits.

The objective of these studies was to evaluate the effect of piglet nursing location on weaning weight, and its dependence on essential oil supplementation on sow and piglet performances. Piglets that nursed anterior teat pairs had heavier weaning weights and higher gain for the lactation period. Additionally, piglet birthweight did not impact their overall teat selection and nursing location. These results provide some insight into the biological aspects of sow milk production, and implied that milk yield may vary between teat pairs along the udder line. Supplementation of essential oils (EO) during late gestation and lactation had no effect on sow fecal dry matter (DM), immunoglobulin content of colostrum and milk, but it did increase the lactose content in milk from sows supplemented with EO, with an increase from 5.84% to 5. 97% (P = 0.04). There was an increase in sow weight loss during lactation (P = 0.002), and there was a significant effect on piglet birthweight, with sows supplemented with EO producing heavier piglets at birth, 1.56 kg in EO sows, compared to 1.49 kg in the control (CON) sows (P = 0.03). Overall, piglet weaning weight is impacted by their selected nursing location along the udder line. Supplementation of EO may have limited effects on sow performance, such as fecal dry matter (DM) but may positively impact piglet birthweight. Furthermore, including EO into sow diets during late gestation and lactation can potentially impact the nutrient levels of sow milk.

A series of experiments was conducted to test the overall hypothesis that reducing the omega-6 (n-6) to omega-3 (n-3) fatty acid (FA) ratio in sow diets would improve sow reproductive performance (characterized by increases in numbers and body weight of piglets born alive and weaned) and would lessen the inflammatory responses of their offspring post weaning. Diets were wheat/barley based and consisted of a control (tallow based, similar to a standard production diet), 3 diets with plant oil based n-6:n-3 ratios (9:1P, 5:1P, and 1:1P) and a 5:1 fish oil diet (5:1F). The control diet had a ratio of 8:1, but contained approximately half the polyunsaturated FA content of the other diets. Sows were randomly assigned to a treatment diet on d 80 of gestation, and remained on that treatment for three consecutive reproductive cycles (gestation/lactation 1 = P1, gestation/lactation 2 = P2, gestation/lactation 3 = P3). Experiment 1 was designed to test the hypothesis that reducing the n-6:n-3 FA ratio in sow diets would increase circulating concentrations of n-3 FA’s in sows and in their offspring, and the passive immune status of piglets would be improved. Performance data was collected throughout P1 and P2 on 150 sows (n = 30/diet). Sow and piglet serum, colostrum and milk were analyzed for FA profiles, and colostrum and piglet serum were analyzed for immunoglobulin (Ig) A and IgG. In P1, birth weights were unaffected by diet (P > 0.05). Average piglet weaning weights (P = 0.02) and ADG (P = 0.01) however, were highest for piglets born to sows consuming the 9:1P and 5:1P diets. During P2, 5:1F sows consumed 10% less feed (P = 0.04), their piglets had reduced birth weights (P = 0.05), and average weaning weight was reduced by 0.8 kg (P = 0.04) relative to control or 5:1P sows. Colostral and piglet plasma IgA and IgG were unaffected by diet (P > 0.05). Colostrum FA profile patterns were similar to that of the sow diets. Serum n-3 FA’s were greatest in sows (P < 0.01) and piglets (P < 0.01) consuming 1:1P or 5:1F diets. Serum α-linolenic acid (ALA) was highest in the 1:1P sows and eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were highest in the 5:1F sows. In piglet serum obtained prior to suckling, ALA and DHA did not differ among treatments (P > 0.05) but EPA was 2.5 times greater in the 1:1P group and 4 times greater in the fish group (P < 0.01) compared to those from the control diet. In post-suckle samples, ALA was highest in serum from 1:1P diet piglets (P < 0.01), and EPA and DHA were highest in piglet serum from the 5:1F sows (P < 0.01). Omega-3 FA’s can perturb lipid metabolism, specifically increasing the lipolytic activity of adipose tissue and thus the second experiment tested the hypothesis that high producing sows, consuming reduced n-6:n-3 ratios would have increased body fat mobilization. Twenty sows per diet, farrowing ≥ 11 piglets and nursing ≥ 10 piglets during P3, were used. Performance data on sows and piglets (such as weights, numbers, backfat changes) was collected throughout lactation and milk samples obtained on d 4 and d 16 of lactation. Jugular catheters were inserted into 8 sows from each of the 9:1P and 1:1P groups on d 5 of lactation and sows were challenged with a single injection of epinephrine followed by serial blood collections. Feed intake was highest for sows consuming the control (8.4 kg/d) and 5:1P (8.2 kg/d) diets and lowest for the sows fed the 1:1P (7.4 kg/d) and 5:1F (7.7 kg/d) diets (P = 0.05). Altering the n-6:n-3 FA ratio did not affect sow BW, piglet ADG, milk DM and N content or the total output of milk (P > 0.2). Sows consuming the 1:1P diet had greater backfat thickness (P < 0.05) and numerically higher plasma NEFA at baseline compared with the 9:1P sows (240 vs 93 uM; P = 0.16). When given epinephrine, 9:1P fed sows tended to have lower net incremental area under the curve (niAUC) glucose (P = 0.08) and numerically higher niAUC NEFA (P = 0.17) and glycerol (P = 0.15). A third experiment was conducted to test the hypothesis that piglets raised by sows consuming reduced n-6:n-3 ratios would have reduced inflammatory responses post-weaning. Piglets (n = 20/diet) raised by sows consuming the treatment diets described above for 2 gestation/lactation cycles (P2) were selected at weaning. Within diet group, pigs were randomized to either a challenge control group (saline injected) or to a lipopolysaccharide (LPS) injected group (n=10/challenge•diet-1). Piglets were fed a common starter diet for 6 days followed by saline or LPS injections on d 7. Rectal temperatures were recorded for 24 hrs and blood samples were collected at 0, 2, 6 and 12 hrs post injection for pro-inflammatory cytokine and blood urea nitrogen (BUN) analysis. Injecting LPS caused decreased feed intake and reduced ADG (P < 0.01), and increased temperature and cytokine production (P < 0.05). Piglets raised by sows consuming the 1:1P diet had elevated temperatures (P = 0.01; diet x challenge P > 0.05). Overall, circulating plasma ALA and EPA were increased in sows and piglets when sows were fed a 1:1 plant based ratio compared to the control or high n-6:n-3 ratio groups. Sows fed a ratio of 1:1 mobilized more body fat relative to those consuming the 9:1 ratio; there were no treatment effects on piglet growth. Reducing maternal n-6:n-3 FA ratios below 5:1 increased piglet body temperature prior to and during an LPS induced inflammatory challenge,. Reducing the sow dietary n-6:n-3 FA ratio below 5:1 may have detrimental effects on piglets due to over-stimulation of inflammatory responses.

In order to investigate if difference in personality is depended on the teat positions in piglets, Sus scrofa, 63 piglets, from 21 litters, were studied. The piglets were at an age between 9 and 31 days. 3 piglets in each of the 21 litters, one that suckled at an anterior teat, one at a middle teat, and one at a posterior teat, were studied during lactation, undisturbed activity, and introduction to a novel object respectively to new straw. In total thirteen behaviors were recorded. The only significant difference between the teat position were disputes during suckling (P=0.018). There was a tendency of playing during undisturbed activity (P=0.062) between the teat positions. There were significant differences between the litters for every behavior except for inactive piglet lying alone (P=0.108) and when exploring new straw (P=0.584). There is only evidence for behavioral differences for the frequency of disputes during suckling between piglets at different teat positions. A principal component analysis, which accounted for 64.2 % of the variance, suggested four personality traits: exploration (19.2 %), playfulness (17.5 %), interest in food (14.8 %), and interest in straw (10.9 %). However, no significant differences were found for these components for the different teat positions.

Tyrimo objektas – Mikotoksinų surišėjo Mycosorb efektyvumas ir poveikis 27-70 dienos amžiaus paršeliams Tyrimo tikslas- išsiaiškinti mikotoksinų surišėjo Mycosorb efektyvumą ir poveikį paršelių mityboje Tyrimo uždaviniai: 1. Paruošti paršelių šertų su mikotoksinų surišėju Mycosorb priesvorio kitimo analizę; 2. Paruošti pašarų konversijos kitimo analizę; 3. Išanalizuoti paršelių šertu mikotoksinų surišėju Mycosorb mirtingumo kitimo dinamikos analizę; 4. Aprašyti priesvorio, pašarų konversijos ir mirtingumo skirtumus kontrolinėje ir eksperimentinėje grupėje; 5. Pateikti išvadas ir rekomendacijas naudojant mikotoksinų surišėją Mycosorb. Mikotoksinų surišėjas Mycosorb pagerino paršelių svorio augimą. Baigiantis bandymui bandomosios grupės paršeliai svėrė 1 kilogramu daugiau nei kontrolinės grupės paršeliai. Rezultatus kurie buvo gauti, galima paaiškinti tuo, kad pašarai, kurie buvo naudojami paršelių mityboje buvo užteršti mikotoksinais ir preparatas Mycosorb efektyviai absorbavo mikotoksinus ir sumažino jų neigiamą poveikį. Pašarų sunaudojimas kontrolinėje grupėje buvo didesnis nei bandomojoje, o svorio priaugimas mažesnis. Mikotoksinų surišėjas Mycosorb turėjo teigiamą poveikį ir bandomosios grupės pašarų konversija buvo mažesnė nei kontrolinės. Bandomosios grupės pašarų konversija buvo 2, o tuo tarpu kontrolinės 2,2. Paršelių grupėje gavusioje pašarus su preparatu Mycosorb viduriavimo atvejų buvo mažiau nei kontrolinėje grupėje. / The object of experiment – The effectiveness and effect of toxin binder Mycosorb to the 27-70 days old piglets. Aims of experiment – to investigate the effectiveness and effect of toxin binder Mycosorb to the digestion of piglets. Tasks of experiment: 1 . To prepare the analysis of weight change of the piglets feed with toxin binder Mycosorb; 2. To prepare graphic presentation of feed conversion change analysis; 3. To examine the analysis of death dynamics in piglets feed with toxin binder Mycosorb; 4. To examine the diarhea change analysis in piglets feed with toxin binder Mycosorb; 5. To record differences of weight gain, feed conversion and death case differences in control and experimental groups; 6. To present the conclusions and recomendations for the use of toxin binder Mycosorb; Toxin binder Mycosorb increased the weight gain. At the end of experiment the tested piglets were weighing 1kilogram more than in control group. These results are explained by the feed which was given to piglets intoxicated with mycotoxins and Mycosorb effectively absorbed with mycotoxins and decreased its negative impact. The consumption of feed in control group was monitored higher and weight gain was lower than in experimental group. The impact of Mycosorb was positive on the feed conversion as the conversion in a experimental group was lower than in control group. The convertion of experimental group equaled 2.0, meanwhile control groups 2.2. The group in which the toxin binder... [to full text]

A number of routine painful procedures such as castration and tail-docking are currently performed in swine production without the benefit of anaesthesia or analgesia. In addition, parturition is generally considered painful. Providing analgesics at the time of castration and tail-docking lowered plasma cortisol levels of the piglets suggesting a reduction in pain associated with the procedures. The use of the non-steroidal antiinflammatory drug meloxicam also resulted in less isolated behaviour of male piglets following castration. Providing meloxicam routinely following parturition did not result in reduced neonatal mortality or piglet growth, but lowered plasma cortisol suggesting a reduction in pain. Producers in the future may need to consider using pain control as part of their standard operating procedures in order improve piglet welfare and meet their consumers’ expectations, but are unlikely to see an economic return associated with improved productivity. / Please do not reject this before tomorrow afternoon. I am going to stop by the Office of Graduate Studies and hand in the necessary documents. / Boehringer Ingelheim (Canada) Ltd. and Ontario Pork

Made available in DSpace on 2014-06-11T19:35:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-04-08Bitstream added on 2014-06-13T20:26:13Z : No. of bitstreams: 1 privadofilho_jr_dr_jabo.pdf: 801638 bytes, checksum: d98f692fdecb81ee726aeb25f6e86da4 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Foram acompanhados 2.514 partos de fêmeas suínas de ordem de parto um e dois, com o objetivo de avaliar as taxas de leitões nascidos totais, vivos, natimortos e mumificados. Foram agrupadas as parições em dois períodos denominados, quente (1º e 4º trimestres) e ameno (2º e 3º trimestres). Dos 28.617 leitões nascidos, a ordem de parto um apresentou 4,7% de natimortos e 2,9% mumificados, e a ordem de parto dois teve uma ocorrência de 5% de natimortos e 2,5 de mumificados. O percentual de natimortos e mumificados foi maior no período quente, nas duas ordens de parição, a maior taxa de natimortalidade foi 6,2% e 7,4% nas duas ordens de parição respectivamente. As maiores médias de leitões nascidos totais também ocorreram no período quente (4º trimestre) 12,35 leitões/leitegada na ordem de parto um e 11,38 leitões/leitegada na ordem de parto dois / The objective of the paper was to follow 2.514 farrows in sows in one and two parity order to evaluate the total piglets born, piglets born alive, stillbirths and mummifies. The farrows were putted together in two periods named: hot season (1th and 4th quarters) and mild season (2th and 3th quarters). The 28.617 piglets born, the parity order one showed 4,7% of stillbirths and 2,9% of mummifies and the parity order two showed 5,0% of stillbirths and 2,5% of mummifies. The percentage of stillbirths and mummifies were higher in the hot season comparing with the mild season, in both parity orders. The highest stillbirth rate was 6,2% and 7,4% in the two parity orders, respectively. The highest average of total piglets born also occurred in the hot season (4th quarter) 12,35 piglets /litter in the parity order one and 11,38 piglets / litter on the parity order two

Orientador: Gilson Hélio Toniollo / Banca: Paulo Henrique Franceschine / Banca: Antonio Carlos Alessi / Banca: Karen Martins Leão / Banca: Fabiana Ferreira Souza / Resumo: Foram acompanhados 2.514 partos de fêmeas suínas de ordem de parto um e dois, com o objetivo de avaliar as taxas de leitões nascidos totais, vivos, natimortos e mumificados. Foram agrupadas as parições em dois períodos denominados, quente (1º e 4º trimestres) e ameno (2º e 3º trimestres). Dos 28.617 leitões nascidos, a ordem de parto um apresentou 4,7% de natimortos e 2,9% mumificados, e a ordem de parto dois teve uma ocorrência de 5% de natimortos e 2,5 de mumificados. O percentual de natimortos e mumificados foi maior no período quente, nas duas ordens de parição, a maior taxa de natimortalidade foi 6,2% e 7,4% nas duas ordens de parição respectivamente. As maiores médias de leitões nascidos totais também ocorreram no período quente (4º trimestre) 12,35 leitões/leitegada na ordem de parto um e 11,38 leitões/leitegada na ordem de parto dois / Abstract: The objective of the paper was to follow 2.514 farrows in sows in one and two parity order to evaluate the total piglets born, piglets born alive, stillbirths and mummifies. The farrows were putted together in two periods named: hot season (1th and 4th quarters) and mild season (2th and 3th quarters). The 28.617 piglets born, the parity order one showed 4,7% of stillbirths and 2,9% of mummifies and the parity order two showed 5,0% of stillbirths and 2,5% of mummifies. The percentage of stillbirths and mummifies were higher in the hot season comparing with the mild season, in both parity orders. The highest stillbirth rate was 6,2% and 7,4% in the two parity orders, respectively. The highest average of total piglets born also occurred in the hot season (4th quarter) 12,35 piglets /litter in the parity order one and 11,38 piglets / litter on the parity order two / Doutor