Aníbal de Sant'Anna Moretti

Leptospira interrogans serovar icterohaemorrhagiae seropositivity and the reproductive performance of sows.

The reproductive performance of 28 sows seropositive to Leptospira interrogans serovar icterohaemorrhagiae was compared with that of 87 Leptospira sp. seronegative dams belonging to the same herd. Sows were sampled during 1988 to 1993. During this period the herd was not submitted to any kind of intervention (antibiotic therapy, immunoprophylaxis or rodent control). Relative risks (RR) of return to heat, mummified fetuses, stillbirth, and weak newborn piglets for infected sows were assessed and the differences in means of total piglets born per litter, piglets born alive, piglets effectively housed, weaned piglets, stillbirths, mummified fetuses, weak newborn piglets, weight at birth of the piglets effectively housed, weight at 21 days of life and weight at weaning were evaluated. Seropositive dams had a greater risk of having weak newborn piglets (RR = 1.67, 1.02 < or = CI 95% < or = 2.72) and also of having more weak newborn piglets per litter (P = 0.01). Other variables examined were not different (P > 0.05).

Causas de mortalidade de leitões neonatos em sistema intensivo de produção de suínos

Two research was conducted to evaluate and to classify the occurrence of the preweaning losses (based on the postmortem findings) of piglets in an intense swine production system, at the west of Sao Paulo State during the year 2000. Among total piglets born alive. 7.19 % died during the first 24 suckling days, but most of them (5.63 %) died on the 1st week of life all over the year. The most important causes of losses were overlaying (2.61 %), weakness (1.45 %), diarrhea syndrome (1.10 %), and genetic defects (0.56 %), occurring mainly on the 1st week of life. Stillbirth rate, in relation to total born, was 5.96 %. Evidences indicated higher number of overlaying during the hottest months of the year, caused probably by the longer staying out of the piglets pen. It was suggested some control measures to reduce the piglets mortality in order to maximize the productive efficiency of the system.

Phosphorus availability of rock phosphates as compared with feed-grade phosphates for swine

Cento e noventa e dois leitoes foram usados em um experimento para avaliar a biodisponibilidade relativa do fosforo (RBP) em seis fontes fosfaticas. As fontes foram tres fosfatos de uso em nutricao (FP), dois fabricados no Brasil e um nos Estados Unidos, e tres amostras de fosfatos de rocha (RP), originados de duas minas brasileiras e uma mina situada em Israel. Os niveis de calcio (Ca), fosforo (P) e fluor (F) nos fosfatos de rocha foram 29, 12 e 1,7% (fonte RP 1), 33, 14 e 1,4% (fonte RP 2) e 30, 14 e 3,6% (fonte RP 3), respectivamente. Os suinos foram alimentados com uma dieta basal de milho e farelo de soja (18% PB, 0,95% Lis, 0,75% Ca, 0,37% P) ou dieta basal contendo 0,15% P a partir de um fosfato bicalcico purificado padrao (SP), ou com 0,15% P a partir das fontes experimentais FP ou RP. Cada dieta foi fornecida a seis baias (replicatas) com quatro leitoes durante 35 dias (14,4 a 39,9 kg). O ganho de peso (WG), a conversao alimentar (FG), o P plasmatico (PP), as cinzas osseas (BA) e a resistencia ossea a quebra de metacarpos e metatarsos (BS-MM) e femures (BS-F) melhoraram com a adicao de fosforo as dietas. Contudo, o desempenho e os parâmetros osseos pioraram com o uso dos fosfatos de rocha, em comparacao a suplementacao dietetica de FP. A analise de regressao dos dados de WG, BA, BS-MM e BS-F em relacao ao P adicional foi realizada e foram calculadas slope-ratios para avaliar a RBP nas fontes de FP e RP. A biodisponibilidade media do P nas fontes FP e RP, relativas ao SP (com valor atribuido de 100), foram 89 e 49% (WG), 112 e 49% (BA), 78 e 28% (BS-MM), e 101 e 52% (BS-F), respectivamente. Baixos desempenho e resistencia ossea relacionados a toxicidade devem ser esperados se fosfatos de rocha forem utilizados na alimentacao de suinos.

Phytogenic feed additives in piglets challenged with Salmonella Typhimurium

The effects of phytogenic feed additives on piglet performance and fecal score (FDD), as well as on lipid oxidation of pork meat were evaluated. One hundred and twenty crossbred weaned piglets were randomly assigned to six treatments according to a 2 × 3 factorial design with five replicates per treatment. Factors were: challenge with Salmonella Typhimurium at 35 days of age or no challenge, and three different additives (control (CTR), basal diet; phytogenic feed additives (PHY), basal diet plus 2000 ppm of phytogenic feed additives - Rosmarinus officinalis, Mentha piperita, Lippia sidoides and Porophyllum ruderale; and antimicrobial agent (ATB), basal diet plus 100 ppm of tylosin, 2000 ppm of zinc and colistin sulfate, 30 ppm in the pre-starter basal diet, 10 ppm in the starter basal diet I and II, and 5 ppm in growth and finishing basal diet). Body weight (BW) of the piglets of ATB was greater throughout the experimental period, without any differences detected between CTR and PHY. Nevertheless, from 96 to 106 days of age, the BW of the CTR group was greater than PHY. From 21 to 34 days of age, feed conversion of ATB was lower than CTR; however, PHY showed an intermediate result, which did not differ from either ATB or CTR. Challenged animals reduced feed intake from day 35 to 48 compared with unchallenged animals. Piglet performance and fecal score from 21 to 48 days of age were lower in piglets that received ATB compared with the other treatments. However, from 35 to 48 days of age, the FDD of PHY was lower than CTR. Lipid oxidation was not reduced in treated animals. Antimicrobial agent improved the growth performance of piglets until 63 days of age, and no difference was observed between the treatments from 64 to 131 days of age. Antimicrobial agent reduced FDD; the FDD of PHY was similar to that of ATB after 48 days. None of the treatments affected lipid oxidation of pork meat.

Estudo comparativo da eficiência de diferentes técnicas de mensuração da concentração espermática em suínos

Artificial Insemination (AI) in swines is a rising technique that has been used during the last years at the swine production systems, because it furnish several advantages to the producers just like boar high efficiency, better breeding control and easiness in introducing foreign genetic materials. Accuracy, precision and robustness for ejaculation volume of spermdensimeter (ESPERMIO) and spectrofotometer (ESPECTRO) in relation to the Neubauer Count, designed as the standard technique, were evaluated objectifying higher performance of AI technique. A total of 142 boar ejaculation was used for spermatic concentration measurement by the techniques described above. The average spermatic concentrations (106 sptz/mL) and average doses number were, respectively: 229.1 and 22.6, 185.0 and 18.5, 283.6 and 28.0 for Neubauer count, Spectrofotometer and Spermdensimeter. ESPECTRO mean bias (accuracy) and bias standard deviation (precision), in relation to the Neubauer count were, respectively - 44.1 and 52.6, while ESPERMIO were 54.4 and 44.8. Through these results its possible to conclude that ESPECTRO has a tendency to subestimate and ESPERMIO to superestimate the spermatic concentration in relation to the Neubauer Count, and that the ESPECTRO was more accurate and less precise than ESPERMIO. Positive effect of ejaculation volume on accuracy and precision in both techniques (ESPERMIO and ESPECTRO) was confirmed by the robustness results.

Avaliação do uso de Hormônio Luteinizante (LH) como indutor da ovulação em porcas

The research, developed in a swine production system, examined the effectivity of luteinizing hormone (LH) in ovulation induction. Twenty four sows compose the control group and tirthy two sows received intramuscular aplication of 600 IU of eCG (Novormon 5000®), 24 h after weaning and 5 mg of LH (Lutropin - V ®), 56 h after eCG injection (treated group). Oestrus were observed twice a day, the ovulation detected by transcutaneous ultrasonography and ovulation rate (OR) determined by corpora lutea counting. The weaning-to-estrus interval (WEI) were reduced (P=0,01) by treatment (87,4 vs 98,5 h). The ovulations occured among 32 and 48 h (37,25 ± 3,65) after LH and were diferent (P < 0,0001) of control (63,67 ± 20,22, range: 32 - 104 h). The OR of treatment was similar (P = 0,2) on the control (23,16 ± 12,19 vs 20,08 ± 5,19, respectively).

Novel Flow Cytometry Analyses of Boar Sperm Viability: Can the Addition of Whole Sperm-Rich Fraction Seminal Plasma to Frozen-Thawed Boar Sperm Affect It?

Boar semen cryopreservation remains a challenge due to the extension of cold shock damage. Thus, many alternatives have emerged to improve the quality of frozen-thawed boar sperm. Although the use of seminal plasma arising from boar sperm-rich fraction (SP-SRF) has shown good efficacy; however, the majority of actual sperm evaluation techniques include a single or dual sperm parameter analysis, which overrates the real sperm viability. Within this context, this work was performed to introduce a sperm flow cytometry fourfold stain technique for simultaneous evaluation of plasma and acrosomal membrane integrity and mitochondrial membrane potential. We then used the sperm flow cytometry fourfold stain technique to study the effect of SP-SRF on frozen-thawed boar sperm and further evaluated the effect of this treatment on sperm movement, tyrosine phosphorylation and fertility rate (FR). The sperm fourfold stain technique is accurate (R2 = 0.9356, p > 0.01) for simultaneous evaluation of plasma and acrosomal membrane integrity and mitochondrial membrane potential (IPIAH cells). Centrifugation pre-cryopreservation was not deleterious (p > 0.05) for any analyzed variables. Addition of SP-SRF after cryopreservation was able to improve total and progressive motility (p < 0.05) when boar semen was cryopreserved without SP-SRF; however, it was not able to decrease tyrosine phosphorylation (p > 0.05) or improve IPIAH cells (p > 0.05). FR was not (p > 0.05) statistically increased by the addition of seminal plasma, though females inseminated with frozen-thawed boar semen plus SP-SRF did perform better than those inseminated with sperm lacking seminal plasma. Thus, we conclude that sperm fourfold stain can be used to simultaneously evaluate plasma and acrosomal membrane integrity and mitochondrial membrane potential, and the addition of SP-SRF at thawed boar semen cryopreserved in absence of SP-SRF improve its total and progressive motility.

Associação de probióticos adicionados à dieta de leitões no aleitamento e na creche: índices zootécnicos e economicidade

The aim of this study was to investigate the effects of probiotics association added to piglets diets in lactation and nursery. A total of 144 piglets from birth to 62 days old were raised. The design with two treatments (Control and Probiotic A) was totally randomized in lactation. In the nursery, randomized blocks with factorial arrangement 2x3 were defined: Probiotic A and Probiotic B; Control and Probiotic B; Probiotic A and Probiotic A; Control and Control; Probiotic A with challenged animals; and Control and challenged animals. At 35 days from birth 48 animals of the nursery were orally inoculated with Salmonella Typhimurium. Average weight, feed consumption, average weight gain and feed conversion were assessed. For economic analysis, the costs of diet during the nursery and income of animal’s sale were calculated. Feed consumption considered for analysis was the one related to the period of 21 to 62 days of life. No effect was observed on evaluated parameters in the maternity. Positive effect was observed on feed conversion for Probiotic A and Probiotic A treatment in nursery. In economic evaluation, Control and Probiotic B treatment showed lower cost compared to other ones, thus representing a satisfactory alternative.

Differences in maternal plane of nutrition and body condition during late gestation coupled with estrus synchronization at weaning do not result in differences in embryonic development at 4 days of gestation

This study was conducted to assess the effects of dietary energy in late pregnancy and hormone therapy at weaning on plasma metabolite profile, litter performance, reproductive parameters, and embryo viability in the second pregnancy. A total of 23 first-parity sows at 75 d of pregnancy were randomly allocated to 4 treatments. Treatments were factorial (2 × 2) combinations of 2 nutritional strategies [standard-energy feed (SEF) and high-energy feed (HEF)] and 2 hormone therapies [600 IU eCG and 2.5 mg swine LH 72 h later (HO) and no hormone (WH)]. Sows were weighed weekly from 75 d of pregnancy until 3 d before farrowing; 1 d after farrowing; 7, 14, and 21 d into lactation; and at weaning. Back fat (BF) was measured at 75 d of pregnancy, 3 d before farrowing, and at weaning. Average daily gain and ADFI were also calculated. Plasma metabolites were analyzed after 82, 89, 96, and 103 d of pregnancy, at farrowing, and after 7, 14, and 21 d of lactation. Embryo viability was assessed after 4.55 d of second pregnancy. During pregnancy, HEF-treated sows displayed greater BW (P < 0.05) compared with SEF-treated females, but no differences were observed during lactation. There were no differences in BW of the piglets caused by the treatments. High-energy-treated females showed superior BF (P > 0.05) in all periods; however, significant differences were detected only at the prefarrowing measurement (P < 0.05). No differences in ADFI were observed during lactation. The SEF group showed positive ADG, whereas the HEF group showed negative ADG (0.216 vs. -0.266 kg/d for SEF and HEF, respectively; P < 0.05). High-energy-treated sows presented greater concentrations of total cholesterol after 89 and 103 d of pregnancy and greater concentrations of high-density lipid cholesterol (HDL) after 89 and 96 d. At farrowing and 14 and 21 d of lactation, NEFA concentrations were greater (P < 0.05) in the HEF group. After hormone treatment, no differences were observed on weaning-to-estrus intervals and estrus duration. Greater mobilization of body reserves observed in the HEF group during lactation did not affect reproductive performance negatively, suggesting that metabolic status was adequate for the first lactational catabolism.

Avaliação da suplementação de vitamina A nas características seminais em reprodutores suínos

The objective of this study was to evaluate the effect of vitamin A feed supplementation on the following boar semen characteristics: volume, motility, vigor, seminal pH, spermatic concentration, total number of spermatozoa, percentage of living sperm cells and morphologic abnormalities. The experiment was carried out with 10 hybrid boars (328.5 ± 2.12 days of age and 191.0 ± 12.0 kg live weight). The boars were separated into two treatments and fed with two vitamin A levels: control, 10.000 UI/kg feed daily; and vitamin A, 16.000 UI. The boars received 2.5 kg feed daily. A randomized complete design was used with replication measurements in time. There was no significant effect of vitamin A supplementation on the characteristics studied, and nor on the time and treatment interaction. The was significant effect of time on pH, spermatic concentration, total number of spermatozoa, percentage of living sperm cells, morphologic abnormalities, motility and vigor. Although detect significant differences were not detected between both treatments, numerical differences were detected indicating that vitamin A influenced the average increase in motility and the percentage of living sperm cells and the reduction in the percentage of morphologic abnormalities. Data showed support the idea that vitamin A is intimately associated with spermatogenesis.