Influence of Pulsation Rate on Udder Health and Teat Thickness Changes in Dairy Ewes

Abstract

In this work on machine milking of ewes, pulsation rates of 120 and 180 cycles per min were compared, both with a pulsation ratio of 50:50 and a vacuum level of 36 kPa, comparing intramammary infection (IMI), somatic cell count (SCC) and teat end thickness changes. To this end, two groups of 20 Manchega ewes were used in a crossover experimental design with two experimental periods of 24 d for each. Bacterial exposure of all teats was increased by dipping them in a suspension of Staphylococcus simulans at four consecutive milkings of each period. Pulsation rate of 180 cycles per min, compared with 120 cycles per min, had no negative effect upon new IMI (11 and 16% of ewes infected, respectively) and SCC. No teat end lesions were observed in those animals milked with the two pulsations assayed. Also, teat thickness changes (-0.38 and -0.36 mm at 120 and 180 cycles per min, respectively) were not affected significantly. Finally, in absence of IMI, the two pulsation rates assayed did not affect the SCC.

Effects of vacuum level and pulsation rate on milk ejection and milk flow traits in Tunisian dairy camels (Camelus dromedarius)

“…On the contrary to ewes (Peris et al 2003) and goats (Lu et al 1991) where higher pulsation rates better stimulate milk ejection reflex, better massage teats, and improve milking efficiency, camels seem to behave as a cow-like animals and prefer to be milked with low pulsation rate.…”

The Course of Machine Milking in Small Ruminants

“…Dzidic et al (2004) in their study stated that the capacity of the udder in Istrian ewes significantly affects the volume of milk production, milking time, average and peak milk flow rates, whereas the teat angle has a negative effect on all traits characterizing the course of machine milking in ewes). As it was reported by Peris et al (2003aPeris et al ( , 2003b, Murciano-Granadina goats rearing twins had a larger capacity of the udder (2.86 l) and a shorter teat-floor distance (23.57 cm) than in the case of nanny goats rearing single kids, where it was 1.60 l and 26.39 cm, respectively. According to the above mentioned authors, the capacity of the udder is positively correlated with body weight (rp = 0.80) and milk production (rp = 0.69).…”

“…At a high frequency of pulsation (180 cycles/minute) and different levels of vacuum (36kPa and 42 kPa) the time of overmilking extended from 1.5 to 2 minutes in the half of the udder throughout 35 days did not influence the frequency of new infections. The percentage of new infections in halves of the udder with overmilking at vacuum levels of 36 kPa and 42 kPa was 10% and 13%, respectively, while in halves without overmilking it was 7% and 11%, respectively (Peris et al, 2003a;2003b). A high frequency of pulsation (180 cycles/minute) and a low level of vacuum (36 kPa) significantly decreased irritation of the teat end during milking (Fig.…”

“…Factors that influence log BTSCC include herd and breed, lactation stage, the course of the drying-off period of animals and milking system (Zeng & Escobar, 1996;Diaz et al, 2004;Zweifel et al, 2005). In machine milking log BTSCC is also influenced by factors such as vacuum level, pulsation frequency and pulsator ratio in milking installations (Billon et al, 1999;Fernández et al, 1999;Sinapis et al, 2000;Peris et al, 2003aPeris et al, , 2003b. In sheep and goats daily milk yield and composition (fat, protein and lactose percentage contents) as well as log BTSCC are also affected by the frequency of milking (Knight & Gosling, 1995;Synapis et al, 2000;Negrão et al, 2001;Salama et al, 2003;Capote et al, 2008) and the use or omission of machine stripping (Knight & Gosling, 1999;Molina et al, 1999;McKusik et al, 2000McKusik et al, , 2003.…”

“…In recent years a trend towards a further reduction in milking vacuum (to 34 -36 kPa) has been observed due to the decreasing mass of milking clusters (Billon et al, 1999). In a study on Manchega ewes creasing the pulse frequency from 120 to 180 cycles per minute at 36 kPa vacuum and a pulsator rate of 50% did not have a detrimental impact on the health status of the udder and teat end condition (Peris et al, 2003b). Optimal conditions of machine milking for goats include pulsation frequency of 70 -90 cycles/minute, at the negative pressure in milking installation of 36 -44 kPa and a 65% pulsator rate (Sinapis et al, 2000).…”