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Immunocastration (ImC) has been proposed as an animal welfare-friendly alternative to reduce sexual and aggressive behavior and to increase carcass fat deposition with positive effects on meat quality. The β -adrenergic agonists ( β -AA) are known as repartitioning agents that acts increasing lean tissue deposition. The combined use of these technologies can positively affect meat quality and increase retail cuts yield. Thus, this research was conducted to evaluate the combined effects of ImC and β -AA (zilpaterol hydrochloride (ZH) and ractopamine hydrochloride (RH)) on retail cuts, bones, and fat trim of feedlot finished Bos indicus (Nellore) cattle. No interaction was observed between sexual condition and diet for any trait. The ImC decreased cold carcass, hindquarter (HQ), forequarter (FQ) and combined brisket, short ribs and flank (BSF) weights. The ImC also showed smaller weights of retail cuts and bones on the HQ and on the FQ than non-castrated (NoC). Fat trim weights did not differ from ImC and NoC. The most of subprimal cuts were heavier in NoC than in ImC. Feeding β -AA did not affect cold carcass weight; however, animals fed ZH had higher weights of HQ and retail cuts in HQ when compared with RH and control (CO) group, with no differences between RH and CO for both traits. The weights of FQ, BSF, retail cuts in FQ, as well as bones and fat trimmings were not affected by β -AA. In summary, ImC decreases carcass and retail cut weights, whereas ZH supplementation leads to an improvement in carcass lean tissue and retail cuts. [ABSTRACT FROM AUTHOR]

Ram sperm membrane displays a particular lipid composition, especially regarding the high quantity of polyunsaturated cholesterol. This trait improves membrane fluidity; however, the spermatozoa become more susceptible to the attack of reactive oxygen species (ROS), which may lead to structural and functional damage, impairment or even impeded fecundity. The aim of the present experiment was to study the resistance of ovine spermatozoa to different ROS. Sperm samples from 4 rams were collected using an artificial vagina. Sperm samples were then incubated (1 h, 37°C) with four ROS inducer mechanisms: xanthine/xanthine oxidase (produces superoxide anion), hydrogen peroxide (4 mM), ascorbate/ferrous sulfate (4 mM; produces hydroxyl radical), and malondialdehyde (MDA, lipid peroxidation product). Samples were analysed using the 3-3′ diamino benzidine (DAB) stain as an index of mitochondrial activity, the eosin nigrosin stain as an index of membrane integrity; the simple stain (fast green/Bengal rose) as an index of acrosome integrity; and the measurement of thiobarbituric acid reactive substances (TBARS) as an index of lipid peroxidation. Results showed that acrosome and membrane integrity as well as mitochondrial potential were highly impaired by hydrogen peroxide, which was not the case for the other ROS (Table 1). Surprisingly, TBARS production was higher in samples incubated with ascorbate and ferrous sulfate (hydroxyl radical). Furthermore, sperm showing impaired mitochondrial potential were negatively correlated with membrane and acrosome integrities (r= -0.83, P< 0.0001 and r= -0.62, P= 0.01, respectively). Results of the present experiment suggest that semen of rams is extremely susceptible to attack by hydrogen peroxide. However, the mechanism by which this substance impairs sperm quality apparently does not involve oxidative stress, because no increase in TBARS was observed. Despite the necessity of further studies to investigate how hydrogen peroxide negatively influences sperm function, the use of catalase and glutathione peroxidase, important hydrogen peroxide scavengers, appears to be an alternative to improve the quality of ram sperm. Table 1.Effect of different reactive oxygen species in semen of ramsThe authors thank Nutricell for the media used in the experiment and CAPES for financial support. [ABSTRACT FROM AUTHOR]

Cryopreservation of equine semen has been widely studied by several research groups because of the large breed and individual variation in sperm freezability. A key factor in sperm cryopreservation is the high incidence of oxidative stress, an imbalance between reactive oxygen species (ROS) and antioxidant protection, which impairs sperm functionality by attacking plasma membrane, acrosome, mitochondria, and DNA. In order to study the resistance of equine spermatozoa to different reactive oxygen species (ROS), sperm samples from 4 Mangalarga stallions were collected using an artificial vagina. Samples were cryopreserved in extenders containing dimethylformamide (DMF) or methylformamide (MF). After thawing and washing, sperm samples were then incubated (1 h, 37°C) with 4 ROS inducer mechanisms: xanthine/xanthine oxidase (produces superoxide anion), hydrogen peroxide (4 mM), ascorbate/ferrous sulfate (4 mM; produced hidroxyl radical), and malondialdehyde (MDA, lipid peroxidation product). Samples were evaluated using the 3-3′ diamino benzidine (DAB) stain, as an indicator of mitochondrial activity; the eosin nigrosin staining, to evaluate plasma membrane integrity; the simple stain (fast green/Bengal rose), to assess acrosome integrity; and the measurement of thiobarbituric acid reactive substances (TBARS), a lipid peroxidation product. Statistical analysis was performed using the Student t-test and LSD test. Results showed that sperm mitochondrial potential of frozen-thawed samples in MF was highly susceptible to the attack of hydroxyl radical and hydrogen peroxide. No effect of ROS was observed on membrane and acrosome integrity. On the other hand, samples cryopreserved in DMF showed no differences in susceptibility to ROS. When evaluating the main effects of different extenders, results showed a higher protective effect of the MF extender on acrosome integrity and mitochondrial potential (MF: 12.1 ± 2.2 and 7.8 ± 2.3% v.DMF: 3.4 ± 0.7 and 1.1 ± 0.7%, respectively, P< 0.05). However, a negative effect of MF extender was observed regarding the percentage of sperm showing intact membrane and TBARS content (MF: 2.0 ± 0.8% and 517 ± 115 ng/106sperm v.DMF: 20.6 ± 1.7% and 118 ± 44 ng/106sperm, respectively, P< 0.05). A strong negative correlation was found between TBARS and plasma membrane integrity (r = -0.88; P= 0.004) for samples cryopreserved in DMF, whereas a positive correlation was found between TBARS and sperm with full mitochondrial potential (r = 0.73; P= 0.04). Results of the present study indicate that DMF may play a role in the protection of sperm against the attack of ROS. However, such action is apparently limited to the plasma membrane. On the other hand, the MF-supplemented extender exerts an intracellular protection. Therefore, the antioxidant therapy, especially hydrogen peroxide and hydroxyl radical scavengers, may be an alternative to improve the post-thaw quality of MF-supplemented cryopreserved semen in stallions, by increasing extracellular antioxidant capacity. The authors thank Nutricell for financial support and the media used in the present experiment. [ABSTRACT FROM AUTHOR]

The study aimed to determine the effects of feeding outdoor-grown hydroponics maize sprouts (HMS) on the growth performance and digestibility of nutrients in goats. Three treatment groups (n = 5), group T1 (control), were fed 500 g concentrate, and Napier grass; T2, 500 g concentrate, and HMS, while T3 had sole feeding of HMS using a completely randomized design. The results showed that HMS had a better feed nutritive composition with the lower concentration of indigestible fibre (P<0.05) and higher concentration of crude protein (12.28%) compared to Napier grass (7.22%) (P<0.05). Goats in T1 and T2 fed with concentrate had a higher average daily gain (ADG) of 79 g/day and 48 g/ day rivalling goats fed with HMS (44 g/day) (P<0.05). Feed conversion ratio (FCR) was significantly better (P<0.05) in goats in T1 and T2 compared to T3. Goats in groups T1 and T2 showed significantly higher dry matter digestibility (69.27% and 63.95%, respectively) and crude protein digestibility (71.89% and 72.28%, respectively) compared to group T3. Sole feeding of HMS exerted a minor impact on growth performance in the animals. However, the HMS could potentially replace the conventionally planted sprouts in conjunction with commercial concentrate to improve the growth performance of the small ruminants. [ABSTRACT FROM AUTHOR]

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Copyright of Archives of Veterinary Science is the property of Archives of Veterinary Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)