Effects of maternal supplementation of trace minerals and fatty acids on beef progeny

Maternal nutrition during gestation affects fetal development, which has long-term programming effects on offspring postnatal growth performance. Trace minerals play very important roles in nutrition and regulate many of the critical biological processes. Additionally, with a critical role in protein and lipid metabolism, essential fatty acids can influence the development of muscle and adipose tissue. Maternal supplementation of trace minerals or fatty acids during gestation could impact fetal development through placental transportation and modification. Thus, the objective of this dissertation was to evaluate the effects of maternal supplementation of trace minerals and fatty acids on physiological responses, including growth performance, carcass characteristics, and gene expression, of the subsequent progeny. Recent studies conducted in ruminant animals have demonstrated that maternal supplementation of trace minerals modifies metabolism, body composition, mineral status, and immune function of the subsequent progeny during the neonatal stage. The objective of experiment 1 was to investigate effects of maternal supplementation with an injectable trace mineral (Cu, Mn, Zn, and Se) on subsequent steer performance during the finishing phase. Seventy-six Angus cross steers [body weight (BW) = 249 ± 42 kg] from dams administered either an injectable trace mineral (TM; Multimin 90) or sterilized physiological saline (SAL) during prepartum stage were used. Prior to artificial insemination (AI), heifers were injected at 221, 319, and 401 ± 22 d of age. After AI, the heifers were injected on 205, 114, and 44 ± 26 d prepartum. Growth performance or mineral status in serum and liver of the steers during finishing phase was not affected (P ≥ 0.14) by maternal treatments. Carcass characteristics were not different (P ≥ 0.18), except steers from TM dams had greater (P = 0.05) percentage of carcasses graded as Choice or greater. Experiment 1 indicates that maternal supplementation of an injectable trace mineral increased the percentage of carcasses graded as Choice or greater, other than that, maternal supplementation had limited influence on finishing phase growth performance, trace mineral status, or carcass characteristics of the subsequent steer progeny. Recent data suggested that maternal supplementation of Ca salts of polyunsaturated fatty acids during late gestation impacts offspring growth performance and carcass characteristics. Thus, experiment 2 investigated the effects of late gestation supplements (77 d prepartum), either rich in saturated and monounsaturated fatty acids (CON; 155 g/cow/d EnerGII) or polyunsaturated fatty acids (PUFA; 80 g/cow/d Strata and 80 g/cow/d Prequel), on cow performance and subsequent calf growth performance as well as mRNA expression in longissimus muscle (LM) and subcutaneous adipose tissue at birth and weaning. There was no difference (P ≥ 0.34) in cow BW or body condition score from pre-supplementation through weaning. Relative concentrations of C18:3n-3 and C20:4n-6 decreased (P ≤ 0.05) to a greater extent from mid-supplementation to calving for PUFA compared with CON cows. Cow plasma C20:0, C20:5n-3, and C22:6n-3 were increased (P ≤ 0.01) in PUFA during supplementation period. At birth, PUFA steers had greater (P = 0.01) plasma C20:5n-3. No differences (P ≥ 0.33) were detected in steer birth BW or dam milk production, however, CON steers tended (P = 0.06) to have greater pre-weaning average daily gain and had greater (P = 0.05) weaning BW compared with PUFA. For mRNA expression in steers, MYH7 and C/EBPβ in LM increased (P ≤ 0.04) to a greater extent from birth to weaning for PUFA compared with CON; MYF5 in LM and C/EBPβ in adipose tissue tended (P ≤ 0.08) to decrease more from birth to weaning for CON compared with PUFA; SCD in PUFA adipose tissue tended (P = 0.08) to decrease to a greater extent from birth to weaning than CON. In addition, maternal PUFA supplementation tended (P = 0.08) to decrease MYOG mRNA expression in LM and decreased (P = 0.02) ZFP423 in adipose tissue during the pre-weaning stage. Experiment 2 indicates late gestation PUFA supplementation decreased pre-weaning growth performance of the subsequent steer progeny compared with CON supplementation, which could have been a result of downregulated mRNA expression of myogenic genes during pre-weaning period. Experiment 3 evaluated the effects of supplements differing in fatty acid profile to late gestational beef cows on steer progeny performance during the finishing phase. Seventy steer progeny (BW = 273 ± 34 kg) from experiment 2 were used for this finishing study. During the finishing phase, no treatment × time interaction or treatment effect (P ≥ 0.21) was detected for steer BW, while PUFA steers tended (P = 0.06) to have greater gain to feed ratio (G:F). Neither carcass characteristics nor relative mRNA expression was different (P ≥ 0.11). In conclusion, maternal supplementation of polyunsaturated fatty acids during late gestation tended to increase steer progeny finishing phase G:F, but no had no effects on finishing phase BW, postmortem carcass characteristics, or mRNA expression of myogenic and adipogenic genes during finishing phase. It was demonstrated in other animals that not only the quantities, but also the balance between n-6 and n-3 fatty acids is important for animal health and growth performance. Experiment 4 used 190 mature fall-calving Simmental × Angus cows (BW = 609 ± 59 kg) to evaluate the effects of late gestation supplementation of fatty acids to beef cows on cow performance, steer progeny growth performance during pre-weaning and backgrounding periods, and relative mRNA expression of genes associated with myogenesis and adipogenesis. Cows were fed either 0.77 kg/cow/d soybean hulls mixed with 0.155 kg/cow/d of EnerGII (SFA/MUFA), 0.77 kg/cow/d soybean hulls mixed with 0.04 kg/cow/d of Strata + 0.12 kg/cow/d of Prequel (PUFA2), or an isocaloric corn-based control supplement (CRN) during the last 82 ± 5 d of gestation. There was no difference (P ≥ 0.11) in cow BW or BCS from pre-supplementation to weaning. Relative concentrations of C18:2n-6 in plasma were greater (P = 0.01) in SFA/MUFA and PUFA2 cows compared to CRN during supplementation. At birth, plasma relative concentration of C17:0, C20:0, C20:3n-6, and C20:5n-3 from PUFA2 steers were greater (P ≤ 0.05) than SFA/MUFA. Concentration of plasma C20:4n-6 from PUFA2 steers was greater (P = 0.02) than CRN and SFA/MUFA. Concentration of C18:2n-6 in PUFA2 steer plasma was greater (P = 0.04) than CRN. Milk yield or proximate composition was not different (P ≥ 0.12) among treatments. Milk C15:0 and total n-3 fatty acids were greater (P = 0.05) in PUFA compared to CRN. There were no differences (P ≥ 0.62) in steer BW at birth, weaning, or the end of the backgrounding period. For mRNA expression in longissimus muscle of steer progeny from birth to weaning, PAX7 decreased to a greater (P < 0.01) extent for SFA/MUFA and PUFA2 steers; expression of GPAT1 and CPT1 mRNA increased to a greater (P ≤ 0.02) extent for CRN steers. Expression of MYH7 mRNA during the pre-weaning period was greater (P = 0.01) in PUFA2. For mRNA expression in subcutaneous adipose from birth to weaning, ZFP423 tended (P = 0.07) to increase to a greater extent for CRN, while CEBPB tended (P = 0.07) to decrease to a greater extent for PUFA2 steers. Experiment 4 indicates that late gestation fatty acid supplementation modified plasma relative concentrations of fatty acids for dams and progeny and modified mRNA expression of genes related to myogenesis and adipogenesis, but had limited effects on progeny growth performance during pre-weaning and backgrounding periods. Experiment 5 evaluated the effects of late gestation supplementation of fatty acids to beef cows on steer progeny finishing phase growth performance, carcass characteristics, and mRNA expression of genes associated with muscle and adipose tissue development. Ninety-one steer progeny (BW = 290 ± 30 kg) from experiment 4 were used for this finishing study. No treatment × time or treatment effect (P ≥ 0.12) was detected for steer progeny BW during the finishing phase. Average daily gain, dry matter intake, or gain to feed ratio was not different (P ≥ 0.24) among treatments. There were no differences (P ≥ 0.17) in carcass characteristics. For relative mRNA expression, there was a tendency (P = 0.09) for SFA/MUFA steers to have greater CEBPA mRNA expression than PUFA2, with CRN being intermediate and not different from the other two treatments. No differences (P ≥ 0.11) were detected for mRNA expression of other selected genes during the late finishing phase. Thus, maternal supplementation of Ca salts of saturated and monounsaturated fatty acids during late gestation tended to increase the mRNA expression of CEBPA in the Longissimus muscle compared to polyunsaturated fatty acids. Other than that, maternal supplementation of Ca salts of fatty acids during late gestation had limited effects on steer progeny finishing phase growth performance, carcass characteristics, and mRNA expression of genes associated with muscle and adipose tissue development. In summary, maternal supplementation of trace minerals or fatty acids during prepartum had limited effects on progeny finishing phase growth performance and carcass characteristics. However, late gestation fatty acid supplementation has the potential to impact progeny plasma fatty acid profile at birth as well as mRNA expression of genes associated with myogenesis and adipogenesis, which might lead to different growth performance.U of I OnlyAuthor requested U of Illinois access only (OA after 2yrs) in Vireo ETD syste

Effects of supplements differing in fatty acid profile to late gestational beef cows on cow performance, calf growth performance, and mRNA expression of genes associated with myogenesis and adipogenesis

Abstract Background Maternal nutrition during gestation affects fetal development, which has long-term programming effects on offspring postnatal growth performance. With a critical role in protein and lipid metabolism, essential fatty acids can influence the development of muscle and adipose tissue. The experiment investigated the effects of late gestation supplements (77 d prepartum), either rich in saturated and monounsaturated fatty acids (CON; 155 g/cow/d EnerGII) or polyunsaturated fatty acids (PUFA; 80 g/cow/d Strata and 80 g/cow/d Prequel), on cow performance and subsequent calf growth performance as well as mRNA expression in longissimus muscle (LM) and subcutaneous adipose tissue at birth and weaning. Results There was no difference (P ≥ 0.34) in cow body weight (BW) or body condition score from pre-supplementation through weaning. Relative concentrations of C18:3n-3 and C20:4n-6 decreased (P ≤ 0.05) to a greater extent from mid-supplementation to calving for PUFA compared with CON cows. Cow plasma C20:0, C20:5n-3, and C22:6n-3 were increased (P ≤ 0.01) in PUFA during supplementation period. At birth, PUFA steers had greater (P = 0.01) plasma C20:5n-3. No differences (P ≥ 0.33) were detected in steer birth BW or dam milk production, however, CON steers tended (P = 0.06) to have greater pre-weaning average daily gain and had greater (P = 0.05) weaning BW compared with PUFA. For mRNA expression in steers: MYH7 and C/EBPβ in LM increased (P ≤ 0.04) to a greater extent from birth to weaning for PUFA compared with CON; MYF5 in LM and C/EBPβ in adipose tissue tended (P ≤ 0.08) to decrease more from birth to weaning for CON compared with PUFA; SCD in PUFA adipose tissue tended (P = 0.08) to decrease to a greater extent from birth to weaning than CON. In addition, maternal PUFA supplementation tended (P = 0.08) to decrease MYOG mRNA expression in LM and decreased (P = 0.02) ZFP423 in adipose tissue during the pre-weaning stage. Conclusions Late gestation PUFA supplementation decreased pre-weaning growth performance of the subsequent steer progeny compared with CON supplementation, which could have been a result of downregulated mRNA expression of myogenic genes during pre-weaning period

Applying real-time quantitative PCR to diagnosis of freemartin in Holstein cattle by quantifying SRY gene: a comparison experiment

Background Freemartinism generally occurs in female offspring of dizygotic twins in a mixed-sex pregnancy. Most bovine heterosexual twin females are freemartins. However, about 10% of bovine heterosexual twin females are fertile. Farmers mostly cull bovine fertile heterosexual twin females due to the lack of a practical diagnostic approach. Culling of such animals results in economic and genetic-material losses both for dairy and beef industry. Methods In this study, a comparative test, including qualitative detection of SRY gene by polymerase chain reaction (PCR), quantitative detection of relative content of SRY by real-time quantitative polymerase chain reaction (qPCR), and quantitative detection of H-Y antigen, was performed to establish the most accurate diagnosis for freemartin. Twelve Holstein heterosexual twin females were used in this study, while three normal Holstein bulls and three normal Holstein cows were used as a positive and negative control, respectively. Results Polymerase chain reaction results revealed that SRY gene were absent in three heterosexual twin females and only two of them were verified as fertile in later age. The qPCR results showed that relative content of SRY was more than 14.2% in freemartins and below 0.41% in fertile heterosexual twin females. The H-Y antigen test showed no significant numerical difference between freemartin and fertile heterosexual twin female. Discussion Our results show that relative content of SRY quantified by qPCR is a better detection method for diagnosis of freemartin in Holstein cattle as compare to qualitative detection of SRY gene by PCR or quantitative detection of H-Y antigen. To the authors’ knowledge, this is the first time we applied qPCR to diagnosing freemartin by quantifying SRY gene and got relative SRY content of each freemartin and fertile heterosexual twin female. We concluded that low-level of SRY would not influence fertility of bovine heterosexual twin female