Heat energy for growing goats and sheep grazing different pastures in the summer.

Abstract

Angora goat, Spanish goat, and Suffolk x Rambouillet sheep wethers (20 of each type; 30.4+/-.57, 31.3+/-.93, and 32.4+/-1.08 kg BW for Angora goats, Spanish goats, and sheep, respectively) were used to investigate influences of animal type and two grass-based pasture treatments on heat energy during summer grazing (mid-August through September in Oklahoma). The improved pasture treatment consisted of .7-ha paddocks primarily of Old World bluestem and johnsongrass, whereas the native pasture treatment entailed 10.8-ha paddocks dominated by big and little bluestems and indiangrass. Grasses were 95 to 100% of diets for the improved pasture treatment and 71 to 95% for the native pasture treatment; forbs were 2 to 25%, and shrubs were less than 4% of diets for the native pasture treatment. Metabolizable energy intake was similar (P > . 10) between pasture treatments but differed (P <.01) among animal types: 79, 99, and 113 kcal/(kg(.75) BW.d) for Angora goats, Spanish goats, and sheep, respectively; SE 7.1. Heat energy estimated via CO2 entry rate was affected by pasture treatment ( P = .08) and animal type (P < .001): improved pasture treatment 109, 132, and 151 kcal/(kg(.75) BW.d); native pasture treatment 126, 138, and 163 kcal/(kg(.75) BW.d) for Angora goats, Spanish goats, and sheep, respectively. Likewise, daylight grazing time was greater (P = .04) for the native than for the improved pasture treatment and differed (P < .01) among animal types: improved pasture treatment 5.3, 4.7, and 6.7 h; native pasture treatment 6.0, 5.7, and 8.1 h for Angora goats, Spanish goats, and sheep, respectively. In conclusion, heat energy during summer grazing of grass-based paddocks was less for goats than for sheep, and animal type can affect the increase in heat energy as energy intake and grazing time increase.

Características de carcaça, componentes não-carcaça e composição tecidual e química da 12ª costela de cordeiros Santa Inês terminados em pasto com três gramíneas no período seco

“…Outro aspecto importante foi a maior participação de GORD na composição da costela dos animais terminados em pasto de capim-aruana e capim-tanzânia, que não diferiram entre si (P>0,05), em relação ao capim-andropogon (P<0,05). A gordura está diretamente relacionada à oferta energética da dieta e tem importante função na conformação, na proteção e nas características organolépticas da carcaça e de seus cortes (Poppi & McLennan, 1995;Herselman et al, 1999). Assim, as variedades tanzânia e aruana utilizadas na alimentação dos ovinos foram determinantes do melhor acabamento de carcaça em detrimento àquelas obtidas com capim-andropogon, resultados confirmados também pela análise química da 12 a costela.…”

Effects of desertification on the body temperature, activity and water turnover of Angora goats

“…Similarly, sheep spent a greater portion of time grazing on pastures which had high levels of soluble carbohydrates (Birrell, 1989), which are abundant in succulent species, such as P. afra, as a result of their crassulacean acid metabolism (Borland et al, 2009). Herselman et al (1999) found that Angora goats that grazed on pasture with a high content of browse had higher heat energy, grazed for longer and took more steps per unit of time spent grazing than did goats that grazed on grass pasture. Our goats on the intact site consumed a high proportion of browse and succulent species such as P. afra (Milne, 2008) and so may have foraged for longer, resulting in higher activity levels than goats that inhabited the transformed site.…”

The 13C bicarbonate dilution technique to determine energy expenditure in young bulls validated by indirect calorimetry

“…These methods have been previously applied mostly in humans. Only, limited information is available on the applicability of the 13 C bicarbonate dilution technique in ruminants (Herselman et al, 1999;Junghans et al, 1997). In pasture systems or other free ranging systems of land use energy requirements of grazing animals are affected by a range of different environmental factors which can not be easily simulated in respiration chambers commonly used to derive energy expenditure.…”