Effect of Zilpaterol Hydrochloride on Performance and Meat Quality in Finishing Lambs

Abstract

Twenty-four Dorper x Pelibuey lambs were housed in individual pens during a 31-d feeding period and assigned to four treatments (n = 6) under a randomized complete block design with different daily doses of zilpaterol hydrochloride (ZH): 0 (control), 0.1, 0.2, and 0.3 mg/kg BW to determine the effects of ZH supplementation on productive performance, meat quality, and wholesale cut yields. Final BW (p = 0.02) and average daily gain (ADG, p = 0.04) were greater in lambs supplemented with 0.2 mg/kg BW. Supplemental ZH tended to improve dry matter intake (DMI, p = 0.008) and ADG:DMI ratio (p = 0.078). Wholesale cut yields were not affected by ZH supplementation. Percentage of head was greater (p = 0.04) in lambs treated with ZH. The ZH supplementation did not affect carcass characteristics. However, longissimus thoracis et lumborum (LTL) presented a linear trend (p = 0.08) of increasing with ZH supplementation. Percentage of blood presented a trend (p = 0.051) of decreasing with ZH supplementation. Also, liver decreased in size (p < 0.05) for treatments where ZH was included. Values of luminosity decreased (p < 0.02) when ZH dosage increased. The value of protein Lowry was greater, with 0.3 mg kg−1 (p = 0.04). Cathepsin B + L was greater in the lambs from the control treatment (p = 0.05). In conclusion, using a daily ZH dosage of 0.2 mg per kg of BW produced the best productive performance, carcass characteristics, and some changes in the meat of hair-breed lambs.

Influences of a Supplemental Blend of Essential Oils Plus 25-Hydroxy-Vit-D3 and Zilpaterol Hydrochloride (β2 Agonist) on Growth Performance and Carcass Measures of Feedlot Lambs Finished under Conditions of High Ambient Temperature

“…As observed in the present study, increases in hot carcass weight, dressing percentage, and LM area, with reductions in fat thickness and KPH, are consistent responses to ZH supplementation [19,20,61]. However, several factors may influence the magnitude of responses when ZH is supplemented, including dose [7,62], supplementation period [63], withdrawal period [64], gender [65], slaughter weight [66], and ZH type (patented or generic [19]. Enhancement in carcass characteristics in the present study may be attributable to increased LM muscle IGF1 expression, and ZH supplementation did not affect IGF2 and mTOR expression.…”

“…Additionally, feed additives may play an important role in amelioration of negative effects of HAHL on productivity. Zilpaterol hydrochloride (ZH), a β2 adrenergic agonist extensively used as feed additive in finishing diets for feedlot cattle in several countries [7], stimulates muscle growth even when lambs were finished under HAHL conditions [8]. Likewise, the use of blends of essential oils as feed additives has gained popularity as a strategy to decrease the negative impact of HAHL on ADG and gain efficiency [9,10] but without improvements on the carcass.…”

Impact of presence of zeolite in diets for lambs supplemented with zilpaterol hydrochloride: Growth performance and dietary energetics

“…The absence of effects on DM intake is the most common response to ZH supplementation in feedlot lambs (Estrada -Angulo et al, 2008;Robles-Estrada et al, 2009b;Rivera-Villegas et al, 2019) and in feedlot cattle (Lean et al, 2014;Castro-Pérez et al, 2021). However, some reports indicate decreases (Cayetano-De-Jesus et al, 2020) or increases (Ríos-Rincón et al, 2010) in DM intake with ZH supplementation. According to Reinhardt et al (2014), the main factors that could affect DMI when ZH is supplemented are the season and the intake level pattern prior to ZH supplementation.…”

“…The beta-agonist zilpaterol hydrochloride (ZH) is another additive extensively used in feedlots in countries in which it is approved (Cayetano-De-Jesus et al, 2020). It is well known that the optimal benefits on growth performance, weight gain, and dietary energetics of lambs are when ZH was supplemented at a rate of 4 to 8 mg kg -1 diet during the last 20 to 40 d of fattening (Ortiz-Rodea et al, 2016).…”

“…It is well known that the optimal benefits on growth performance, weight gain, and dietary energetics of lambs are when ZH was supplemented at a rate of 4 to 8 mg kg -1 diet during the last 20 to 40 d of fattening (Ortiz-Rodea et al, 2016). Although, several factors could affect the magnitude of responses when ZH is supplemented, such as dose (Estrada-Angulo et al, 2008;Cayetano-De-Jesus et al, 2020), supplementation period (Vahedi et al, 2015), withdrawal period (Robles-Estrada et al, 2009a), gender (Montgomery et al, 2009), slaughter weight (Castro-Pérez et al, 2021), type of ZH (patented or generic, Rivera-Villegas et al, 2019), and environmental factors (Macías-Cruz et al, 2013), few studies have reported the effects of combining ZH with other additives such antibiotics in feedlot diets (Hilton et al, 2009;Montgomery et al, 2009). However, to our knowledge, the potential interactions between ZH and other ingredients widely used in animal diets have not been investigated so far.…”