No abstract

The aim of this study was to determine the period of genital tubercle (GT) migration using ultrasonography in Morada Nova sheep foetuses (n = 117) from natural mating (NM) and frozen embryo transfer (ET) to determine the window when foetal sexing can be determined. The examinations were performed using transrectal ultrasonography with a dual-frequency linear transducer (6.0 and 8.0 MHz) from day 30-54 of pregnancy at 48-h intervals. The period of GT migration of foetuses produced by NM varied from 36 to 46 days of pregnancy, resulting in an average of 39.5 +/- 2.9 days. For foetuses derived from ET, GT migration varied from 42 to 52 days of pregnancy with an average of 48.5 +/- 3.3 days, being possible the GT of foetuses from ET start to migrate 96 h later even if they are of the same gender. Migration of the GT occurred earlier (p < 0.05) in foetuses produced by NM and sexing accuracy for triplet pregnancies (77.8%) was significantly inferior (p < 0.05) to single (100%) and twin (92.9%) pregnancies for foetuses derived by NM. The results allow one to conclude that foetal sexing can be done from the 50th day onwards in foetuses produced by NM and from the 55th day onwards in foetuses derived from ET, and that multiple pregnancies compromise the sexing accuracy by ultrasonography.

Based on low 18:0 contents observed in milk fat of cows fed cactus cladodes (CC), we hypothesized that including Opuntia stricta cladodes in a soybean oil (SO)‐supplemented diet would promote incomplete rumen biohydrogenation of supplemental PUFA, leading to increased trans‐11 18:1 and cis‐9, trans‐11 CLA contents in milk. Twelve Holstein cows were used in a two‐period study: (a) Baseline: all cows received a total mixed ration (TMR) composed of sorghum silage (SS) and a concentrate containing no SO for 14 days; (b) Treatment: cows received one of the following SO‐supplemented diets for 21 days: (1) SS‐TMR: a TMR composed of SS and a SO‐enriched concentrate, (2) CC‐TMR: a TMR containing CC as a partial substitute for SS plus the SO‐enriched concentrate, and (3) CC‐PMR: same diet as in treatment 2, but CC were mixed with the SO‐enriched concentrate and fed as a partial mixed ration (PMR). Both CC diets increased relative abundances of trans‐11 18:1, cis‐9, trans‐11 CLA, and 18:2 n‐6 in milk fat, whereas opposite effects were observed on 18:0 and cis‐9 18:1. Proportion of 18:2 n‐6 increased, and cis‐9, trans‐11 CLA tended to increase with CC‐PMR as compared to CC‐TMR, whereas 18:3 n‐3 was higher with CC‐PMR than with SS‐TMR. Proportions of several odd‐ and branched‐chain fatty acids, certain 18:1 isomers, and trans‐9, cis‐11 CLA changed with CC diets, notably with CC‐PMR. Milk yield and intake of most nutrients (except fibre) increased or tended to increase with the CC diets, whereas gross milk composition was unaltered. Stearoyl‐CoA desaturase‐1 index for C18 (SCD18) was higher with CC‐PMR than with SS‐TMR, and milk n‐6:n‐3 FA ratio and apparent transfer of 18:2 n‐6 to milk increased with CC diets. These results indicate that Opuntia stricta cladodes can be a valuable feed ingredient for improving the nutraceutical value of milk fat.

Spineless cactus is an important part of dairy cow diet in the semiarid Brazilia. Severe infestation of cochineal (Dactylopius opuntiae Cockerell) destroyed a vast area of the most common species of cactus planted in the region; Opuntia ficus-indica Mill. resistant varieties with superior agronomic performance were recently selected, but they still need to be tested with dairy cows. We evaluated the use of a resistant variety, ‘Orelha de Elefante Mexicana’ (OEM, Opuntia spp.), in dairy cow diet. We tested its effect on intake, nutrient digestibility, microbial protein, blood parameters and performance of lactating cows. Ten cows with an average milk yield of 20 kg/day were assigned to an experiment using a double 5 × 5 Latin square design. The experimental diets consisted of five replacement levels of Nopalea cochenillifera Salm Dyck cv. (‘Miúda’) by ‘OEM’ (0%, 25%, 50%, 75% and 100%) on a dry-matter (DM) basis) and were formulated considering the ingredient composition. The roughage:concentrate ratio was 70:30 on a DM basis. The replacement of ‘Miúda’ by OEM did not change the intake (kg/day) of DM (18.0), organic matter (16.3), crude protein (CP, 2.8), total digestible nutrients (11.6), non-fibre carbohydrates (7.6) and neutral detergent fibre (5.7), or the apparent digestibility (g/kg) of DM (655), organic matter (694), CP (739) and non-fibre carbohydrates (950), whereas apparent digestibility of neutral detergent fibre increased linearly. Microbial protein production (1.5 g/day), microbial protein efficiency (129.2 g CP/kg total digestible nutrients), plasma urea nitrogen (21.4 mg/dL), nitrogen balance (123 g/day), feed efficiency (1.1), nitrogen efficiency (0.2), milk production (20.0 kg/day), fat-corrected milk production (20.1 kg/day) and milk composition were not influenced by the replacement. Therefore, we recommend the use of OEM in the diet of lactating cows with an average milk yield of 20 kg/day.

RESUMO Objetivou-se com este trabalho avaliar a diversidade genética do gene HSP-70.1 e associar os polimorfismos encontrados com a performance de vacas leiteiras das raças Holandesa, Girolando (5/8H-G) e Sindi criadas em região do semiárido brasileiro. Os polimorfismos foram identificados e avaliados pela técnica de PCR-RFLP, usando-se a enzima de restrição EcoRII. Avaliou-se a variabilidade genética por meio do índice de diversidade padrão e da análise de variância molecular (AMOVA). Os polimorfismos identificados foram avaliados sobre as características de produção de leite. Foram identificados sete alelos, os quais demonstraram que houve polimorfismo para a região gênica analisada, e alguns alelos foram compartilhados entre os rebanhos. As raças bovinas Holandesa e Sindi foram similares geneticamente para o gene analisado. A AMOVA demonstrou que há variação genética entre os rebanhos e dentro deles, com a maior parte da variação ocorrendo dentro dos rebanhos para todos os grupos avaliados. Houve efeito dos alelos identificados sobre a produção de leite dos rebanhos das raças Holandesa (P<0,0001) e Girolando (P<0,0117). O gene HSP-70.1 foi polimórfico na população de bovinos leiteiros estudada, sendo, portanto, um marcador molecular promissor para avaliar a produção de leite de raças criadas em região semiárida.

No abstract

O presente estudo teve a finalidade de identificar o sexo e de determinar o dia da migração do tubérculo genital (TG) de fetos ovinos através da ultra-sonografia em tempo real. O sexo foi identificado no Experimento I (EI) levando-se em consideração a localização do TG e no Experimento II (EII), a presença do pênis, prepúcio e bolsa escrotal no feto macho e das tetas, vulva e clitóris no feto fêmea. No EI, as fêmeas (n=17) foram monitoradas em intervalos de 12 horas, do 35o ao 46o dia de gestação, por via transretal com transdutor linear (6,0 e 8,0 MHz). No EII, as fêmeas (n=30) com gestação de 55 a 75 dias foram examinadas apenas uma vez, utilizando-se o mesmo transdutor e via de exame do EI. Das 17 fêmeas do EI, 11 (64,6%) tiveram seus fetos corretamente sexados, independente da gestação ter sido simples (7/11), dupla (3/11) ou tríplice (1/11). Nas 6 (35,4%) gestações restantes, 3 (17,7%) foram duplas, sendo impossível sexar um feto de cada gestação. Nas outras 3 (17,7%) gestações, os fetos foram corretamente sexados, apesar dos nascimentos não coincidirem com a quantificação. Num feto macho de uma gestação simples, a migração ocorreu no 37° dia e até o 46°, todos os fetos das outras gestações estavam corretamente sexados. Das 30 fêmeas do EII, 16 (53,4%) apresentaram gestações simples e a acurácia da sexagem foi de 100%. Nas 14 (46,6%) restantes, as gestações foram duplas, sendo impossível, em quatro casos, determinar o sexo de, pelo menos, um dos gêmeos. De todos os fetos nascidos, a acurácia geral da sexagem foi de 88,0% (EI) e 90,9% (EII), não sendo observada diferença (P>0,05) entre ambos os experimentos. Os resultados permitem concluir que a ultra-sonografia em tempo real é um método eficiente para diagnosticar o sexo fetal pela visualização do TG, assim como pela identificação do pênis, prepúcio e bolsa escrotal no feto macho e das tetas, vulva e clitóris no feto fêmea, desde que os exames sejam realizados a partir do 50o dia de gestação.

No abstract