Produção, composição e rendimento em queijo do leite de ovelhas Santa Inês tratadas com ocitocina

Abstract

RESUMO -Objetivou-se avaliar a produção, a composição e o rendimento (na fabricação de queijos) do leite de ovelhas Santa Inês tratadas ou não com ocitocina. Os animais foram mantidos em regime de confinamento e receberam uma dieta com 12% de PB e 65% de NDT. As ovelhas foram distribuídas em dois tratamentos: ordenha manual com injeção endovenosa de três UI de ocitocina e ordenha manual sem injeção de ocitocina (grupo controle). Realizou-se uma ordenha diária, de modo que, até a desmama, as ovelhas permaneceram diariamente com os cordeiros durante 14 horas. Os cordeiros foram desmamados aos 60 dias e as ovelhas continuaram sendo ordenhadas uma vez ao dia até o final da lactação. Foram coletadas amostras de leite para análise dos teores de gordura, de sólidos totais e de sólidos desengordurados. A duração média da lactação foi de 225±27,24 e 210±38,77 dias para as ovelhas controle e tratadas com ocitocina, respetivamente. Até os 133 dias de lactação, o tratamento com ocitocina (141,63±51,52 kg) foi superior ao controle (89,39±16,65 kg), entretanto, durante todo o período de lactação, não diferiu (169,64 ± 71,05) do controle (119,72±32,73). As porcentagens de gordura (5,84±0,44 e 4,96±0,47), sólidos totais (17,40±0,42 e 16,18±0,57) e sólidos desengordurados (11,57±0,15 e 11,22±0,25) no leite foram influenciadas pela aplicação de ocitocina. Os resultados revelaram diferença significativa para as ovelhas tratadas com ocitocina, as quais apresentaram maior produtividade e, inclusive, melhor composição química do leite. A aplicação de ocitocina é recomendada para animais não adaptados à rotina de ordenha. O leite das ovelhas Santa Inês apresentou rendimentos de 4,80; 8,29 e 5,99 L/kg para os queijos tipo azeitão, pecorino e roquefort, respectivamente.Palavras-chave: gordura, hormônio, lactação, ovino Effects of oxytocin on milk yield and composition of Santa Inês ewesABSTRACT -The objective of this trial was to investigate the effects of oxytocin on milk yield and composition and on cheese yield of Santa Inês sheep receiving a diet containing 12% CP and 65% TDN. Animals were maintained in pens and were assigned to one of the following two treatments: hand milking plus an intravenous injection of 3 IU of oxytocin or hand milking without oxytocin injection (control group). Ewes were milked daily and remained with their lambs for a daily period of 14 hours until weaning; lambs were weaned at 60 days of age and ewes still milked once a day until the end of lactation. Milk samples were collected for analysis of fat, total solids, and solids non-fat. Lactation length averaged 225±27.24 and 210±38.77 for control and oxytocin-treated ewes, respectively. Ewes receiving oxytocin yielded more milk (141.63±51.52 kg) than those on the control group (89.39±16.65 kg) until 133 days of lactation; however, total milk yield on the entire lactation did not differ significantly comparing oxyitocin-treated (169.64 ± 71.05) with control (119.72±32.73) animals. Milk contents of fat (5.84±0.44 and 4.96±0.47), total solids (17.40±0.42 and 16....

Production, composition and processing of milk from ewes fed soybean seeds

“…C14:0 originates from the synthesis on this tissue and, consequently, almost all the cis double bond inserted at carbon 9 of the C14:1 results from this enzyme activity. Ribeiro et al (2007) produced Roquefort type cheese matured for 90 days, using the milk from Santa Inês ewes, and reported yield of 16.70 g/100 g of milk, a value close to those observed in this study (Table 8). Similarly, Zhang et al (2006) manufactured cheese with milk from 1/2 East Friesian × 1/2 Lacaune sheep fed diets containing linseed and sunflower.…”

“…Ribeiro et al (2007) evaluated milk production in Santa Ines ewes receiving oxytocin and reported a production peak at 35 days with 2.23 L day −1 , with overall average production throughout lactation of 0.82 L day −1 . Oilseeds are added to the diet supplied to dairy sheep to increase diet energy density while aiming at increasing milk production, as well.…”

“…It is expected that the crossbred F1 sheep resulting from the crossing will produce more milk than the maternal breeds; however, this was not observed in this study, given that F1 ewes produced on average 439.85 mL over the 56 lactation days (Table 4), which is lower than the production values observed for pure Ile de France sheep: 1.190; 1.310; 1.220; and 890 mL at 14, 28, 42 and 56 days of lactation, respectively (Podleskis et al, 2005). Ribeiro et al (2007) evaluated the composition of milk from Santa Inês ewes that were receiving oxytocin and found higher values (Table 5) of total solids (17.40 g/100 g of milk), solids not fat (11.57 g/100 g of milk), and fat (5.84 g/100 g of milk). On the other hand, Mughetti et al (2012) observed differences in the composition of milk from Santa Inês ewes fed the control and linseed-supplemented diets, with (per 100 g of milk) 5.91 and 6.10 g fat; 4.81 and 4.90 g protein; 3.74 and 3.83 g casein; and 4.77 and 4.86 g lactose in the milk from ewes fed the control diet (without linseed) and a diet with linseed, respectively.…”

Cheese yield in Brazil: state of the art

“…Ribeiro et al (2007) Evaluate production, composition and yield (of cheese manufacturing) of Santa Inês sheep milk treated or untreated with oxytocin. Damián et al (2008) Evaluate components, casein fractions and yield in production of goat cheese milk from Saanen and AngloNubiana breeds.…”

“…Neves-Souza & Silva (2005), Ribeiro et al (2007), Conceição et al (2009), Marques et al (2011) and Fava et al (2014 relate the volume of milk used to make one kilogram of cheese or curd, in order to measure industrial yield, according to Equation…”