Uso do diluente água de coco em pó (ACP-103®) na conservação prolongada do sêmen do varrão: avaliação in vitro e in vivo

O sêmen de oito reprodutores foi coletado e de cada ejaculado separou-se um total de 1,75x10(9)sptz, com concentração de 35x10(6)sptz/mL. Usou-se o Beltsville Thawing Solution (BTS) como controle para testar o diluente água de coco em pó (ACP). O dia de coleta foi o dia zero (D0), sendo o sêmen conservado durante cinco dias, com análises diárias no D0 e nos quatro dias seguintes (D1, D2, D3 e D4). A avaliação da qualidade espermática baseou-se nos resultados do vigor espermático, da porcentagem de células móveis, da morfologia espermática, da integridade da membrana plasmática e dos resultados de fertilidade. As avaliações do vigor espermático (4,1) e da porcentagem de espermatozoides móveis (91%) ficaram acima dos parâmetros mínimos exigidos (3,0 e 70%) para sua utilização em programas de inseminação artificial, pois não houve influência sobre as variáveis analisadas pelo protocolo experimental. O resultado médio da resistência osmótica foi de 71,3% de espermatozoides com cauda enrolada. Não houve diferenças entre os dois diluentes testados para a característica células com acrossoma intacto (BTS = 67,1%; ACP = 71,2%). O sêmen diluído em ACP apresentou maior número de células vivas (77,7 %) com membrana plasmática íntegra (74,2%) após a conservação. A escolha do diluente ACP é aconselhável para uso de rotina em laboratórios que trabalhem com conservação de sêmen suíno. Apesar dos bons resultados in vitro obtidos com o diluente ACP, o BTS apresentou os melhores resultados de fertilidade, 86,7% e 96,7%, respectivamente.The semen of eight boars was collected and a total of 1.75x10(9) spermatozoa were separated from each ejaculate, obtaining a concentration of 35x10(6)sptz/mL. The Beltsville Thawing Solution (BTS) was used as control, being tested the powder coconut water as extender (PCW). The day of collection was considered day zero (D0), and the semen was conserved for five days, with analyses on D0 and on four subsequent days (D1, D2, D3, and D4). The evaluation of spermatic quality was based on the results of spermatozoa vigour, cells motility, spermatic morphology, plasmatic membrane integrity, and fertility. The evaluations of the in natura semen presented mean values of spermatozoa vigour (4.1) and mobile spermatozoids percentage (91%) above the demanded minimum parameters (3.0 and 70%) for its use in artificial insemination programs without influencing on the analyzed variables. The mean results of the osmotic resistance were excellent, with 71.3% of spermatozoids with coiled tail. There were no differences between the two extenders tested for the characteristic cells with intact acrossome (BTS = 67.1%; PCW = 71.2%). The semen diluted in PCW extender presented a higher number of alive cells (77.7%) with a complete plasmatic membrane (74.2%) after conservation period. The choice of PCW extender is advisable for the routine use in laboratories that work with conservation of swine semen. In spite of the good results in vitro with the PCW extender, the BTS presented the best fertility results, 86.7% and 96.7%, respectively

Maximizing farrowing rate

Farrowing rate can be defined as: 1) the number of mated females that farrow within a contemporary group per total number of MATED females for this group or 2) the number of females that farrow within a contemporary group per total number of EXPOSED females for this group. Generally, the first definition is used when hand-mating, whereas the second definition has to be used when pen-mating. Regardless of the definition, farrowing rate can be maximized only by taking total control of the breeding herd. High farrowing rates will result when fertility is high in boars, sows, and gilts; however, excellent management must be used to maintain high fertility in males and females. North Carolina State University data have shown a high correlation between farrowing rate and live pigs born per bred sow per year (Figure 1). Their data show that for each 10% increase in farrowing rate of bred sows, there is a corresponding increase of 2.63 live pigs born per sow per year. In light of these data, pork producers should strive to maximize farrowing rate. This can be done by providing good management during prebreeding, breeding, and gestation phases. The purpose of this article is to provide information on possible management practices to use during each of these phases

Comparação entre diferentes métodos de inseminação artificial em suínos Comparison between different methods of artificial insemination in swine

O objetivo deste trabalho foi avaliar três métodos de inseminação artificial(IA) no suíno em relação ao tempo de infusão e perdas por refluxo da DI durante a IA e aos 120 minutos após a IA, bem como dados de operacionalidade medido pelo grau de dificuldade verificado para execução da IA e dados de desempenho reprodutivo. Foram utilizadas 604 matrizes até a parição 7 e IDE < 7 dias. As fêmeas foram inseminadas em 3 tratamentos: T1= método auto IA com pipetas longas lameladas (Supertip®), sêmen acondicionado em flexitubos® e aparato de IA constituído por uma cinta abdominal e uma mala dorsal; T2= método intermediário, pipetas Supertip®, flexitubos® e sem aparato de IA; T3= método tradicional, pipetas tipo Melrose, sêmen acondicionado em bisnagas e sem aparato de IA, onde o tempo de IA ficou atrelado ao desempenho do funcionário. O tempo médio de IA foi diferente (P<0,02) entre os três tratamentos (1,7&plusmn;1,6; 2,2&plusmn;1,8 e 3,6&plusmn;1,1 minutos para T1, T2 e T3 respectivamente). Em uma parte dos animais (108 fêmeas distribuídas nos 3 tratamentos) foram coletados os refluxos até 120 minutos transcorridos das IAs por meio de uma bolsa de colostomia fixada na vulva . O volume de refluxo durante a IA foi maior (P<0,02) em T1 (7,7&plusmn;13,5mL) quando comparado a T3 (5,8&plusmn;10,8mL). Não foram verificadas diferenças entre os tratamentos no número de espermatozóides eliminados por refluxo até 120 minutos após a IA. Independentemente do tratamento, em torno de 70% do volume e 30% do total de espermatozóides contidos na DI foram eliminados por refluxo em até duas horas após a IA. Na avaliação do grau de dificuldade, foi verificado que, no T1= 85,6%, no T2= 92,9 e no T3= 97,7% das fêmeas tiveram suas inseminações concluídas com até uma intervenção (P<0,05 entre todos os tratamentos). Com relação as taxas de retornos ao estro, taxa de parto ajustada e número de leitões nascidos não foram observadas diferenças entre os tratamentos (P>0,05). As taxas de retorno ao estro foram 10,3, 7,4 e 8,5 %, a taxa de parto ajustada foi de 90,8, 94,0 e 91,7% com 10,9, 11,1 e 11,1 leitões nascidos totais em T1, T2 e T3, respectivamente. O método auto IA e o método intermediário proporcionam IAs mais rápidas e podem substituir o método tradicional sem prejuízos ao desempenho reprodutivo.<br>This study was performed to compare the Hands-free insemination method, i.e., the high degree automation procedure, with an intermediate method, which allows less participation of the inseminator during the application of the inseminating dose (ID), and the conventional method, which is widely used in Brazil. The comparison was based on infusion time and losses due to semen backflow during AI and 120 minutes after AI, degree of difficulty experienced during AI procedure, and reproductive performance data. A number of 604 sows on the parity up to 7 and a weaning to estrus interval < 7 days were used. Females were distributed into 3 treatments: T1= hands-free AI method, with long coilable shaft pipettes (Supertip®), semen stored in flexitubes® and AI device consisting of an abdominal belt and a saddlebag; T2= intermediate method, Supertip® pipettes, flexitubes®, without AI device; T3= traditional method, Melrose-type pipettes, semen stored in tubs, without AI device. AI time was associated with the inseminator’s performance. The average AI time was different (P<0.02) among treatments (1.7&plusmn;1.6; 2.2&plusmn;1.8 e 3.6&plusmn;1.1 minutes for T1, T2 and T3 respectively). One hundred eight sows distributed into the three treatments, had the semen backflow collected up to 120 minutes after AI in a colostomy bag fixed by the vulva. Semen backflow volume during AI was higher (P<0.02) in T1 (7.7&plusmn;13.5 mL) as compared to T3 (5.8&plusmn;10.8 mL). There were no differences among treatments in the number of spermatozoa eliminated by semen backflow up to 120 minutes after AI. Regardless of the treatment, nearly 70% of the volume and 30% of the total spermatozoa contained in the ID were eliminated by semen backflow up to 2 hours after AI. Concerning the degree of difficulty of the AI procedure, 85.6%, 92.9 and 97.7% of T1, T2 and T3 females were inseminated with up to 1 intervention (P<0,05 between all treatments). There were no differences among treatments (P>0.05) in return to estrus rate, adjusted farrowing rate and number of born piglets. The return to estrus rates were 10.3, 7.4 and 8.5%, adjusted farrowing rates were 90.8, 94.0 and 91.7%, with 10.9, 11.1 e 11.1 total born piglets in T1, T2 and T3, respectively. The Hands free method and the intermediate method allowed faster AI and can replace the traditional method without influence on the reproductive performance

Foreign direct investment and country risk: Further empirical evidence

Global political and economic changes over the last decade have resulted into massive capital inflows to developing countries, most of these flows are foreign direct investments. In light of threats of political instability in the forms of civil wars, illegal capital flight, financial market instability, and political corruption, etc., further assessment of country risk is warranted. We examine the relationship between FDI and political and economic risks for 26 countries for the years 1992, 1993, and 1994 by using regression analysis and cross section data. The results indicate a significant relationship between FDI and these risks. This study provides more reliable estimates by using a current and eclectic measurement of risks represented by Euromoney indexes of political and economic risks. In the previous studies the perception of risk was narrowly defined and also political instability events were mistakenly interpreted as political risks.