Performance and digestive characteristics in dairy cattle maintained under grazing regime and supplemented with linseed.

Linseed is characterized by the rich unsaturated fatty acids and slow release of oil in the rumen. The objective of the present study was to evaluate the intake, rumen degradability, and digestibility of dairy cattle maintained under grazing regime and supplemented with linseed. Twelve Girolando (¾ Holstein × ¼ Gir) cows with a mean age of 5.2 ± 1.9 years and body weight of 583.9 ± 67.6 kg were used. The cows were maintained in a rotational grazing system on the mombaça grass (Panicum maximum) and divided into 2 experimental groups. The CONTR (n = 6) group received only the base diet (pasture) and the LINS group (n = 6) received pasture plus linseed. Initially, a fifteen-day adaptation period was established to stabilize the desired consumption amount. After this period, the animals received 800 g of linseed for 126 d. The ruminal degradability was evaluated using 2 males with a cannula in the rumen, and they were provided the same experimental diet. The measured dry matter production of pasture did not show differences during the experimental period. The intake of crude protein and ethereal extract was higher, whereas neutral detergent fiber content was lower in the cows supplemented with linseed. However, this did not alter the weight gain and digestibility coefficients, except the digestibility coefficient of the ethereal extract. At the ruminal level, linseed showed low effective and potential degradability with negative effect on grass degradability.Título em português: Desempenho e características digestivas em bovinos leiteiros mantidos em regime de pastoreio suplementados com linhaça

Parameters blood and viability oocyte Girolando's breed supplemented with linseed (Linum usitatissimum L.) - preliminary results.

The aim of this study was to evaluate the effect of supplementation with linseed on plasma concentrations of glucose, albumin and cholesterol, as well as the quality of oocytes obtained by ovum pick-up (OPU).Proceedings of the 30th Annual Meeting of the Brazilian Embryo Technology Society (SBTE); Foz do Iguaçu, PR, Brazil, August 25th to 27th, 2016, and 32nd Meeting of the European Embryo Transfer Association (AETE); Barcelona, Spain, September 9th and 10th, 2016. A150. Folliculogenesis, Oogenesis and Superovulation. Título em português: Parâmetros sanguíneos e taxa de viabilidade oocitária de vacas girolando suplementadas com linhaça (Linum usitatissimum l.) – resultados preliminares

Effect of the calving-FTAI interval on pregnancy rate and gestational losses in primiparous beef cows.

The aim of this study was to evaluate the influence of the FTAI-calving interval, according to animal category, on the fertility of beef cows. Early Nelore primiparous cows (n = 879; 24 ± 3.3 months; BCS 2.75 ± 0.42), and conventional Nelore primiparous cows (n = 2370, 36 ± 4.6 months, BCC 3 ± 0.48) were enrolled. The average number of days after calving and the day of FTAI artificial insemination (PPP-AI) for Early PosPartum cows was 68.55 ± 22.87 days and for conventional primiparous cows it was 65.26 ± 21.32 days. Data from 6 reproductive seasons from commercial farms (2019-2023) were evaluated. Cyclicity was not considered in our study. On d-11, cows were treated with 1 mg of estradiol benzoate (Gonadiol®; Zoetis, SP, Brazil), i.m., and a first use, intravaginal progesterone-releasing device containing 1.0 g of progesterone (P4) was inserted (DIB®; Zoetis, SP, Brazil). On d-2 the P4 device was removed followed by the i.m. injection of 12.5 mg of PGF (Lutalyse®; Zoetis, SP, Brazil), 0.6 mg of estradiol cypionate (ECP®, Zoetis, SP, Brazil), and 300 IU of eCG (Novormon®, Zoetis, SP, Brazil). FTAI was performed on d-0. Pregnancy diagnosis was carried out at 32 and 120 days after AI. Optimal cut-off points for determining the relationship between the days PP and pregnancy status at first postpartum TAI were studied. The ROC curve analyses identified that the ideal interval between calving and TAI was 49.5 days PP for conventional primiparous cows (AUC = 0.54; P = 0.0004) and 56.5 days PP for early primiparous cows (area under the curve 0.53; P = 0.062). Therefore, in each animal category, the cows were separated into two groups: Early Primiparous - EEP (EEP, n = 584; PPP-AI 47.60 ± 6.0 average days), Late Pos- Partum - ELP (ELP, n = 295; PPP-AI 66.05 ± 11.65 average days), Conventional Primiparous: Early Pos-Partum - CEP (CEP, n = 699; PPP-AI 42.65 ± 6.5 average days) and Late Pos- Partum - CLP (CLP, n = 1671; PPP-AI 63.96 ± 11.31 average days). Pregnancy by AI (P/AI) and gestational losses (GL) before and after the ideal cut-off point were calculated by logistic regression, and the variables farm, reproductive season and BCS were included in the model. The P/IA of early cows was 50.68% (296/584) and 59.66% (176/295) for EEP and ELP, respectively (P = 0.014). The GL was 13.85% (41/295) for EEP cows and 9.65% (17/176) for ELP cows (P > 0.05). The P/AI was 47.5% (332/699) and 55.95% (935/1671) for CEP and CLP, respectively (P 0.05). This study highlighted the importance of specific management strategies, in terms of calving-TAI interval, for early and conventional primiparous cows. So, we conclude that the interval between calving-FTAI interval for early primiparous cows (57 days PPP) should be 7 days longer than for conventional primiparous cows (50 days PPP), with significant impacts on the conception rate.Edição dos resumos da 37ª Annual Meeting of the Brazilian Embryo Technology Society, 2024, Atibaia, SP

Suplementação com gordura protegida na produção de leite de búfalas Murrah (Bubalus bubalis): resultados preliminares.

Objetivou-se avaliar o efeito da suplementação com gordura protegida na produção de leite de búfalas Murrah.Na publicação: MELO-STERZA, F. A

Anatomofisiologia do ciclo estral de fêmeas bovinas.

O objetivo é revisar os conhecimentos sobre a dinâmica de crescimento e desenvolvimento dos folículos ovarianos, e relacioná-los com a ultrassonografia.Cap. 1. E-book

Effects of narasin on the pregnancy rate of Nellore cows maintained under grazing and performance of calves - preliminary results.

Ionophores have been used to improve forage conversion in animal protein and to increase nutrient utilization efficiency in cattle. The effects of the mineral mix (MM) with addition of narasin (Zimprova®; Elanco, Brazil) on the performance of calves and pregnancy rate of Nellore cows were evaluated.Edição dos Proceedings of the 32nd Annual Meeting of the Brazilian Embryo Technology Society (SBTE)

Sucessivas aspirações foliculares guiadas por ultrassonografia não alteram a população folicular antral e a viabilidade oocitária de vacas Girolando.

Objetivou se avaliar se o número de aspirações afeta a população folicular antral ovariana (PFAO) e a taxa de viabilidade oocitária de vacas Girolando submetidas à essa técnica.Na publicação: SOUZA-CÁCERES, M. B.; MELO-STERZA, F. A

Antral follicle count classification selects fertile heifers without influencing the carcass traits.

This study aimed to evaluate the ovarian structure, estrus intensity, ultrasound carcass measurements, and pregnancy rate of Nelore breed heifers and cows in accordance with antral follicle counts (AFCs). We evaluated 503 heifers and 565 Nelore cows, with a mean age of 15.5±2.2 and 69.8±36.1 months, respectively, submitted to a fixed-time artificial insemination (FTAI) protocol. On day zero, all bovine females were examined using ultrasound to determine the AFC. The mean AFC of the heifers and cows were 20±8.6 and 22.5±8.4, respectively. The rib-eye area (REA) and fat thickness (FT) of the heifers (n = 119 for REA and n = 219 for FT) were measured using ultrasound imaging. The average conception rates at the first FTAI and at the end of the breeding season were 35.8% and 57.5%, respectively, for heifers and 45.1% and 78.9%, respectively, for cows. We demonstrated that the probability of pregnancy at the first FTAI and at the end of the breeding season for both young heifers and cows increased as the AFC decreased (P>0.001 and P=0.0123, respectively). FT and REA showed no correlation with AFC in heifers. The intensity of estrus expression was negatively correlated with AFC (-0.46; P<0.0001). In conclusion, Nelore heifers and cows with low AFC had a high probability of pregnancy during the entire breeding season. Thus, AFC can be used as a tool to select heifers with increased fertility without affecting carcass traits (REA and FT)

Efeitos de ionóforos sobre consumo e digestibilidade aparente dos nutrientes em bovinos mantidos à pasto.

A utilização de ionóforos na nutrição de ruminantes vem ganhando destaque por melhorar a eficiência energética e desempenho dos animais. O objetivo foi avaliar os efeitos de fornecimento de ionóforos sobre o consumo e digestibilidade dos nutrientes em bovinos a pasto

Supplementation with protected FAT in the dairy buffalo cows pregnancy rate.

The objective of this study was to evaluate the effect of supplementation with rumen-protected fat source (RPF, palm oil) on the pregnancy rate of dairy buffalo cows submitted to FTAI.Proceedings of the 31st Annual Meeting of the Brazilian Embryo Technology Society (SBTE); Cabo de Santo Agostinho, PE, Brazil, August 17th to 19th, 2017. Abstracts