Low pasture allowance until late gestation in ewes: behavioural and physiological changes in ewes and lambs from lambing to weaning

Abstract

Low pasture allowance during gestation affects ewes' BW at parturition, the bond with their lamb, lamb development, and thus also may affect their responses to weaning. The objectives were to determine if native pasture allowance from before conception until late pregnancy affects ewe-lamb behaviours at lambing, ewes' milk yield, lambs' BW, and the behavioural and physiological changes of ewes and lambs at weaning. From 23 days before conception until 122 days of pregnancy, 24 ewes grazed on two different native pasture allowances: high (10 to 12 kg of dry matter (DM)/100 kg of BW per day; HPA treatment; n = 12) or low (5 to 8 kg of DM/100 kg of BW per day; LPA treatment; n = 12). Thereafter, all ewes grazed on Festuca arundinacea and received rice bran and crude glycerine. Ewes' body condition score (BCS) and BW were recorded during pregnancy and postpartum periods. Milk yield was determined on days 32, 41 and 54 after lambing. Lambs' BW was recorded from birth until 72 days after lambing. Latency from parturition until the ewe licked her lamb, maternal behaviour score (a test that evaluates maternal attachment to the lamb) and latency for lamb to stand up and suckle were determined. The behaviour of the lambs and ewes was recorded before and after weaning (at 65 days). The ewes' serum total protein, albumin and globulin concentrations were measured before and after weaning. The HPA ewes presented greater BW ( P < 0.005) and BCS ( P < 0.005) than the LPA ewes during pregnancy and postpartum (P < 0.04), and had a greater milk yield than the LPA ewes ( P < 0.03). Treatments did not influence any behaviour at lambing, lambs' BW, neither the ewes' behavioural and physiological changes at weaning. HPA lambs paced and vocalized more than LPA lambs ( P < 0.0001). The variation of albumin concentration before and after weaning was greater in the HPA lambs than in the LPA lambs ( P < 0.0001). In conclusion, although ewes' BW, BCS and milk production were affected by pasture allowance until late pregnancy, this did not affect the behaviours that lead to the establishment of the mother-young bond, nor the ewes' behavioural responses at weaning. Lambs reared by ewes that grazed on low pasture allowance during pregnancy presented fewer behavioural changes and a lower decrease of albumin concentration after weaning. Lambs' BW was not affected by the feeding received by their mothers.

Ejaculation does not contribute to the stress response to electroejaculation in sheep

“…Serum total protein, albumin and CK concentrations and plasma glycaemia were determined using commercial kits (Bio-Systems, Barcelona, Spain). Serum globulin concentration was estimated by subtracting the serum albumin concentration from the serum total protein concentration (Freitas-de-Melo, Ungerfeld, Hötzel, Orihuela, & Pérez-Clariget, 2016).…”

Semen collection by trans‐rectal digital stimulation and insemination campaign in goat

“…Semen collection by AV is a preferable method when compared to EE due to these concerns. In addition, after the freezing-thawing processes, sperm quality has been found lower than other collection methods (Freitas-De-Melo, Ungerfeld, Hötzel, Orihuela, & Perez-Clariget, 2017;Ungerfeld et al, 2016). Furthermore, the semen quality obtained with EE differs in terms of its lower spermatological quality, (Santiago-Moreno et al, 2011), higher pH (Giriboni, Lacuesta, & Ungerfeld, 2017;Ungerfeld et al, 2016) and seminal plasma characteristics (Marco-Jimenez, Vicente, & Viudes-de-Castro, 2008).…”

“…Furthermore, the semen quality obtained with EE differs in terms of its lower spermatological quality, (Santiago-Moreno et al, 2011), higher pH (Giriboni, Lacuesta, & Ungerfeld, 2017;Ungerfeld et al, 2016) and seminal plasma characteristics (Marco-Jimenez, Vicente, & Viudes-de-Castro, 2008). In addition, after the freezing-thawing processes, sperm quality has been found lower than other collection methods (Freitas-De-Melo, Ungerfeld, Hötzel, Orihuela, & Perez-Clariget, 2017;Ungerfeld et al, 2016). Another critical issue is the presence of contaminants and urine in semen during the application of EE (Palmer et al, 2005).…”

Maternal nutritional restriction during gestation impacts differently on offspring muscular and elastic arteries and is associated with increased carotid resistance and ventricular afterload in maturity

“…From the same cohort of sheep (mothers and descendants), data related to physiological changes and behavioral issues (i.e., ewe-lamb bonding and behaviors at lambing and at weaning) and their association with pasture allowance during pregnancy were previously published. 20,21 From 23 days before insemination until 122 days of gestation, ewes (mothers, "M" prefix) were randomly assigned to one of the two nutritional management methods: (1) normal feeding or high native pasture allowance (M-HPA) or (2) nutritional restriction or low pasture allowance (M-LPA). 20,21 Hence, the "control" group (M-HPA) was constituted by ewes who had normal availability of nutrients during pregnancy, and the under-nourished group of mothers (M-LPA) by ewes exposed to a nutritional restriction (~50-75% of the usual amount of forage offered) during approximately the first 2/3 of pregnancy.…”

“…20,21 From 23 days before insemination until 122 days of gestation, ewes (mothers, "M" prefix) were randomly assigned to one of the two nutritional management methods: (1) normal feeding or high native pasture allowance (M-HPA) or (2) nutritional restriction or low pasture allowance (M-LPA). 20,21 Hence, the "control" group (M-HPA) was constituted by ewes who had normal availability of nutrients during pregnancy, and the under-nourished group of mothers (M-LPA) by ewes exposed to a nutritional restriction (~50-75% of the usual amount of forage offered) during approximately the first 2/3 of pregnancy. Animals from the M-HPA group had access to 10-12 kg/dry matter/100 kg of body weight per day and those from the M-LPA group had access to 5-8 kg dry matter/100 kg of body weight per day.…”