Short-term dietary concentrate supplementation during estrus synchronization treatment in beef cows increased IGF-I serum concentration but did not affect the reproductive response

Abstract

The objective of this study was to evaluate if short-term dietary concentrate supplementation increased IGF-I serum concentration and resulted in a reproductive response during estrus synchronization treatment in non-lactating beef cows. Thirty non-lactating beef cows (Bos indicus × Bos taurus) were allocated to the same pastureland and fed native tropical grasses as a basal diet. Cows were synchronized using a 7-day CO-Synch plus controlled internal drug release (CIDR) protocol and received fixed time artificial insemination (FTAI). Cows were divided into two groups; the control group (n = 16) received 0.5 kg of concentrate/cow/day, whereas the supplemented group (n = 14) received 4.0 kg of concentrate/cow/day. The period of supplementation was 10 days from the day of CIDR insert to FTAI. The concentration of IGF-I increased (P < 0.05) in the supplemented group, while no significant changes were observed in the control group. Moreover, at the time of insemination, IGF-I serum concentrations were higher in supplemented cows compared with control cows (P < 0.05). Notably, metabolite and insulin concentrations did not differ (P > 0.05) between treatment groups or sampling day. The response to estrus induction, measured as estrus presentation, ovulation rate, and pregnancy rate, was similar between experimental groups (P > 0.05). In conclusion, our results indicated that supplementation with dietary concentrate for 10 days in non-lactating beef cows changed the endocrine milieu, specifically increasing IGF-I serum concentration. However, these endocrine changes did not affect response to estrous induction treatment.

Estrous Signs and Progesterone Profile of Ongole Grade Cows Synchronized at Different Ages Fed Different Level of Dietary Crude Protein

“…To date, a large number of studies have reported the effect of dietary protein concentrate on estrous behavior and reproductive performance of dairy cattle (Law et al, 2009) and beef cattle (Rosales-Torres et al, 2016;Sonjaya et al, 2020). However, there are high variabilities of duration, signs, and intensity of the displayed estrous among individuals and breeds (Moran et al, 2010).…”

Sincronización del estro y ovulación en hembras bovinas de razas cárnicas. Bases endocrinas y protocolos usados

“…Si el ovocito ovulado no es fecundado, alrededor de los días 16 y 17 del ciclo estral, el endometrio secretará PGF2α para inducir la regresión del CL (Rosales-Torres & Guzmán, 2011;Sartori & Barros, 2011). Para esto, la PGF2α al unirse a su receptor en los vasos sanguíneos del CL causa una elevación de Ca++ intracelular para inducir vasoconstricción.…”

“…En vacas lactando tratadas con el protocolo basado en GnRH con y sin el uso de DIP por 7 días, el tiempo entre la aplicación de PGF2-α y la IA, así como los resultados de la TPES reportados fueron muy variables (figura 4C y 4D). En vacas lactando en las que se usó del DIP por 7 días, la TPES más alta (71%) se reportó cuando la IATF se realizó a las 48 (Lamb et al, 2001) y 72 horas (Nash et al, 2012), mientras que la más baja (38%) fue cuando la IA se hizo a las 72 horas (Rosales-Torres et al, 2017). Busch et al (2008), muestran que la TPES es mayor cuando la IA se hace a las 66 horas que cuando se realiza a las 54 horas después del ABANICO VETERINARIO E-ISSN 2448-6132 abanicoveterinario@gmail.com https://abanicoacademico.mx/revistasabanico-version-nueva/index.php/abanico-veterinario Creative Commons (CC BY-NC 4.0) retiro del DIP.…”

“…D) Distribución de datos de TPES a diferentes tiempos entre la aplicación de PGF2-α y la IA en vacas lactantes tratadas con protocolos basados en GnRH sin uso de un DIP. Datos recopilados de: Martínez et al, 2000;Bishop et al, 2017;Bridges et al, 2014;Macmillan et al, 2020;Burns et al, 2008;Busch et al, 2007;Busch et al, 2008;Cruppe et al, 2014;Dahlen et al, 2010;Echternkamp & Thallman, 2011;Esterman et al, 2016;Geary et al, 2001;Giles et al, 2013;Hall et al, 2017;Helguera et al, 2018;Hill et al, 2014;Hill et al, 2016a;Hill et al, 2016b;Kasimanickam et al, 2006;Kasimanickam et al, 2014;Kasimanickam et al, 2009;Kasimanickam et al, 2012;Knickmeyer et al, 2019;Lamb et al, 2001;Lamb et al, 2006;Larson et al, 2006;Marquezini et al, 2011;Marquezini et al, 2013a;Marquezini et al, 2013b;Martínez et al, 2002;Mercadante et al, 2015;Mialot et al, 2003;Nash et al, 2012;Oosthuizen et al, 2018a;Oosthuizen et al, 2018b;Oosthuizen et al, 2018c;Rosales-Torres et al, 2017;Small et al, 2009;Stevenson et al, 2003;…”

Effect of dietary energy source on pregnancy rates and reproductive physiology of pastured beef heifers

“…Research focused on improving the reproductive efficiency in beef females has been ongoing for many years (Diskin and Kenny, 2014). Certain tools such as artificial insemination, embryo transfer, and in vitro fertilization, can be used by producers in the beef industry to improve reproductive efficiency and genetic selection intensity (Rosales-Torres et al, 2017). Despite the advantages these reproductive management tools have to offer, their adoption, particularly in the US, has been slow due to producers concerns related to increased expenses, labor, and risk (USDA, 2017).…”