Size at birth and adult fat mass in twin sheep are determined in early gestation

Abstract

Key points• Reduced size at birth and shorter gestation length are both associated with increased risks of non-communicable diseases (NCD) in later adult life.• Twins are born both smaller and earlier than singletons and adult twins also are reported to be at increased risk of common NCDs such as diabetes.• The smaller size and shorter gestation length of twins has been presumed to be due to a lack of intrauterine space and/or limitations of placental nutrient supply in late gestation, but there are few data to support this.• We show that size at birth and adult fat mass in twin sheep are determined largely in early gestation.• Knowledge of the mechanisms underlying early pregnancy determination of fetal growth and gestation length in twins are likely to increase understanding of how early pregnancy factors influence lifelong health for offspring from all pregnancies.Abstract Size at birth is related to adult health outcomes. Twins are born smaller than singletons; this has been assumed to be secondary to limited nutrient supply in late gestation. We hypothesised that growth trajectory in twins, and the adult consequences of being conceived a twin, are determined in early gestation. Twin pregnancies in sheep were randomised to reduction of one twin on day 42 of a 148 day pregnancy by intra-thoracic KCl (Reductions, n = 46) or a sham procedure (Twins, n = 22). Singleton-bearing ewes also underwent a sham procedure (n = 27). Ewes lambed spontaneously. Linear measures of size at birth were similar in Twins and Reductions, and significantly less than in Singletons. Birthweight was lower in Twins and Reductions than in Singletons, and less in Twins than in Reductions (means (SEM): Singletons, liveborn n = 23: 6.59 (0.17) kg; Twins, liveborn n = 36: 5.23 (0.16) kg; Reductions, liveborn n = 27: 5.76 (0.15) kg; all comparisons P < 0.05). Reductions grew most rapidly between birth and weaning (Singletons, 20.0 (0.4) g kg −1 day −1 ; Twins, 20.0 (0.3) g kg −1 day −1 ; Reductions, 21.0 (0.3) g kg −1 day −1 , P < 0.05) and were of similar weight as Singletons by weaning; Twins remained smaller by weaning but grew most rapidly thereafter (Singletons, 1.6 (0.1) g kg −1 day −1 ; Twins, 2.1 (0.1) g kg −1 day −1 ; Reductions, 1.6 (0.1) g kg −1 day −1 , P < 0.01), so that all groups had similar weight at 2 years. However, Twins and Reductions had greater percentage fat mass than Singletons at 2 years (Singletons, 11.1 (1.1)%; Twins, 14.8 (1.2)%; Reductions, 15.5 (1.1)%, P < 0.05). Thus, in twins, fetal growth trajectory, linear size at birth and adult fat mass are largely determined in early gestation. If this is also true in humans, there are important implications for interventions aimed at optimising fetal growth and pregnancy outcome. Abbreviations βHBA, beta hydroxybutyrate; CRL, crown-rump length; CV, coefficient of variation; DXA, dual energy X-ray absorptiometry; FFA, free fatty acids; HPA, hypothalamic-pituitary-adrenal; IGF-1, insulin-like growth factor-1; RIA, radioimmunoassay.

Efecto de la raza paterna en características de la canal de corderos para carne en Hidalgo, México

“…The opposite occurred in the yield carcass, both hot and cold (Table 1), because the females had a yield 3 % higher than males (P0.05). This is consistent with other authors that assessed the effect of sex on terminal crosses (15,17,18) . It seems that females have an advantage due to the grater amount of fat in the carcass (16) , as well as by the greater weight of the viscera, head and skin of the Cuadro 1.…”

“…Los machos superaron a las hembras (P0.05) en el peso al sacrificio (+15.9 %), el peso de la canal caliente (+12.3 %) y el peso de la canal fría (+11.3 %), lo que coincide con los resultados de otros autores (15,16) , mientras que lo opuesto se observó en el rendimiento en canal, tanto caliente como fría (Cuadro 1), donde las hembras tuvieron un rendimiento 3 % mayor que los machos (P0.05), lo cual concuerda con otros autores que evaluaron el efecto del sexo en cruzamientos terminales (15,17,18) , ventaja que tienen las hembras debido a la mayor cantidad de grasa en la canal (16) , así como por el mayor peso de las vísceras, la cabeza y la piel de los machos (18) . El rendimiento en la canal es de gran utilidad porque indica la proporción del peso vivo que puede ser comercializada como producto final (carne, grasa y hueso), información que puede ser complementada con la evaluación de la composición tisular y regional de la canal.…”

“…En la primera interacción (Figura 1) no se observaron diferencias entre los corderos machos (P0.05), pero sí entre las hembras (P0.01), en donde las hijas de padres Charollais superaron a las de padres Dorset y Texel, lo que por un lado podría explicarse debido al mayor rendimiento que tuvieron las hembras en la canal caliente, y por otro debido a la superioridad de los corderos (machos y hembras) hijos de padre Charollais sobre los hijos de padre Dorset y Texel en el área del ojo males (18) . The carcass yield is useful because it indicates the proportion of live weight that markets as a final product (meat, fat and bone), information that complements with the evaluation of the regional and tissue carcass composition.…”

Epigenetics and developmental programming of welfare and production traits in farm animals

“…These sheep studies suggest that there may indeed be long-term 'programming' of adiposity, particularly in the normally leaner males, and that this is not necessarily associated with differences in birthweight. In contrast, there are several studies (Louey et al 2005;De Blasio et al 2007;Wallace et al 2011b;Hancock et al 2012) suggesting that low birthweight, often as a consequence of placental insufficiency, is associated with increased adiposity in both young and old offspring. Studies in runted pigs (IUGR) show not only fewer muscle fibres in later life compared with their high birthweight littermates, but also increased adipose tissue depot weights and reduced postnatal growth rates (see Brameld et al 2003).…”

Effect of pre- and postnatal growth and post-weaning activity on glucose metabolism in the offspring

“…Both twin and singleton pregnancies are common in sheep, leading to differences in birth weight and post-weaning growth (Hancock et al 2012). Only twin-bearing mothers were selected for this study, hence it is not possible to ascertain whether similar interventions designed to affect postnatal growth rates would lead to identical outcomes in singleton offspring.…”