Lactation curve of Beetal goats in Pakistan

Abstract

Abstract. This study was accomplished with the objective to determine parameters of lactation curves in Beetal goats using Wood’s model. Therefore, milk yield data on 127 Beetal goats maintained at five different government farms were recorded from post-kidding to drying off of does. Wood model parameters were estimated using non-linear regression and individual curves were fitted. The characteristics/parameters of lactation curve were computed. The mean initial yield »a«, rate of increase »b« and rate of decline »c« parameters in Wood’s model for Beetal were 1,214.97, 0.3690 and 0.1196, respectively with R2 value of 98.2 %. The value of percent squared bias (PSB) and the persistency were 0.13 and 60.2%, respectively with mean square error value of 38.45. Flock effect was a significant (P<0.01) source of variation for all the lactation curve parameters, PSB and persistency. Parity did not affect significantly any of the parameters. Type of birth significantly influenced parameter »a«, Time to reach peak (TPY) and lactation milk yield (LMY). Sex of kid also did not affect significantly any of the parameters. Age of doe was significant for parameters »a«, »b«, »c«. Quadratic effect of age was non-significant for all parameters and characteristics. Lactation length significantly affected parameter »a«, »b« and LMY.

Lactation Curve and Milk Production Traits of Syrian Damascus Goats

“…This estimate is higher than the means of 0.08 kg/week and 0.005 kg/week that demonstrated by Ayasrah et al (2013) and Siqueira et al (2017) of Damascus goats in Jordan and of dairy goats in Brazil, respectively. Conversely, the obtained estimate is lower than that of 0.12 kg/week reported by Takma et al (2009) and Waheed and Khan (2013) of Bornova goats in Turkey and Beetal goats in Pakistan, respectively. Within each classification in the same column, means followed by different superscript letters differ significantly; ** (P<0.01); NS: not significant; Parameter (a): the initial milk yield (kg) after kidding; Parameter (b): the rate of rise in milk production to peak lactation (kg/week); Parameter (c): the rate of decrease in milk production from peak to the end of lactation (kg/week).…”

“…PMY was calculated as PMY, kg = a (b/c) b e -b , and PW, weeks was calculated as PW = b/c. Persistency of lactation (P, %) was calculated as P % = Milk L/Milk F * 100, where Milk L is milk production after peak and Milk F is milk production before the peak (Waheed and Khan, 2013).…”

Goat type: The key factor to produce goat milk with economic profitable purpose in arid and desert zones

“…This goat has a great adaptability to produce high quality and high volume of milk in desert zones reaching between 0.95 to 1.561 Kg of milk per day during first lactation period using early goats (1-2 years old) and around 1.640 Kg of milk per day using mature goats (3 to 7 biological years) (Maltz and Shkolnik, 1980). A similar result was described for Beetel goat in Pakistan, where mature goats produce more milk than early goats during first lactation period (Waheed and Khan, 2013). Regarding milk quality in Black Bedouin goat, during its first four lactation periods, the content of protein, fat and lactose were stable and around of 3.5%, 5.5% and 5%, respectively (Shkolnik et al, 1980).…”

The goat farming management for arid and desert zones: a technical approach to produce high quality milk during all the year

“…Besides, they showed that type of birth and age of the doe affected the lactation curve, but not the parity and the sex of the kids. In fact, they proposed that from lactation curve is possible to evaluate the performance of each doe, take decision about the renewal of the herd or make changes in the management procedures to improve milk production (Waheed and Khan, 2013).…”