Methionine Supplementation during Pregnancy of Goats Improves Kids' Birth Weight, Body Mass Index, and Postnatal Growth Pattern.

The last third of gestation is a period of high energy and protein demand for the dam to support fetal growth and the following onset of lactation. Methionine is an essential amino acid that contributes to protein formation, fetal development, and milk synthesis; thus, is likely to have positive effects on the weight and size of the newborn and, afterward, milk yield and milk composition, which may improve growth patterns of the progeny. To test these hypotheses, we used 60 pregnant multiparous Alpine goats with similar live weights and gestational ages (~Day 100 of pregnancy; Mean ± SD; 1410 ± 14 days old and 50.4 ± 6.6 kg) and were separated into two groups: control and supplemented with the delivery. Treatments were T-MET (n = 30; received 1% herbal methionine Optimethione® dry matter based on from Day 100 of the pregnancy to delivery) or T-CTL (n = 30; served as the control and did not receive methionine). The methionine powder provided individual supplementation and was adjusted every week as the live weight and dry matter intake changed. At birth, the weight, body mass index (BMI), birth type, and sex of the kids were determined. Subsequently, the progeny was weighed weekly up to weaning. Two weeks after parturition, the milk composition was recorded weekly, and the milk yield was recorded monthly. The maternal live weight at the start (Mean ± SEM; T-CTL: 50.5 ± 1.1 vs. T-MET: 50.3 ± 1.3 kg) and end (T-CTL: 54.2 ± 1.3 vs. T-MET: 52.8 ± 1.4 kg) of the experiment did not differ statistically among treatments (p > 0.05); however, daily live weight changes tended to differ between groups (T-CTL: 73 ± 10 vs. T-MET: 51 ± 7 g day−1; p = 0.06). The birth weight (T-CTL: 3.1 ± 0.1 vs. T-MET: 3.5 ± 0.1 kg; p < 0.001), daily live weight change (T-CTL: 121 ± 6 vs. T-MET: 141 ± 6 g day−1; p < 0.01), and weaning weight (T-CTL: 8.3 ± 0.2 vs. T-MET: 9.3 ± 0.3 kg; p < 0.01) differed between treatments. The BMI at birth (T-CTL: 0.28 ± 0.01 vs. T-MET: 0.3 ± 0.01 units kg m−2; p < 0.01) and at weaning (T-CTL: 0.85 ± 0.1 kg vs. T-MET: 1.00 ± 0.06 units kg m−2; p < 0.05) differed between treatments. Milk components (protein, fat, lactose, and solids non-fat) and milk yield were similar between treatments (p > 0.05). It is concluded that the inclusion of methionine in the maternal goat diet during the last third of gestation increases the birth and growth variables of the progeny but without significant influence on the milk yield and composition.

Effect of Replacing Sorghum Stubble with Tillandsia recurvata (L.) on Liveweight Change, Blood Metabolites, and Hematic Biometry of Goats.

Tillandsia recurvata is an epiphyte that grows on the canopy of many trees in tropical and subtropical areas of America. The objective of this study was to evaluate the effect of partial or complete substitution of sorghum stubble with T. recurvata on liveweight change, metabolic profile, and complete blood count of goats fed increasing levels (0, 30, and 60%, dry matter basis) of T. recurvata. Thirty non-pregnant three-year-old, non-lactating, healthy mixed-breed goats, ten animals per treatment (T0, T30, and T60), were adapted to diets and facilities for 14 days (d-14). Blood samples were collected at d-15, 28, and 56. At the last phase of the trial (from days 67 on), control goats tended to gain more (p = 0.09) weight than their counterparts consuming T. recurvata. Plasma protein, glucose, triglycerides, calcium, and phosphorus concentrations did not differ among dietary treatments (p > 0.05). Dietary treatment influenced red blood cells (higher for T60; p < 0.01), white blood cells (higher for T30; p < 0.05), mean corpuscular volume (higher for T0; p < 0.001), and mean corpuscular hemoglobin concentration (higher for T0; p < 0.01), although not the rest of the blood variables (p > 0.05). The hematocrit percentage tended to be higher (p = 0.06) in T30 than T0 and T60. It was concluded that replacing sorghum stubble with T. recurvata did not modify the metabolic status and maintained live weight of goats. Nevertheless, the use of T. recurvata as feed for goats would improve the nutrition of these animals in the dry season compared to the current diet obtained from an arid rangeland, reducing production costs, and would alleviate the damage caused by this aggressive epiphyte to host trees.

Milk Yield and Composition of Mixed-Breed Goats on Rangeland during the Dry Season and the Effect on the Growth of Their Progeny.

We tested whether the milk yield capacity of mixed-breed goats on a Chihuahuan desert rangeland in northern Mexico during the dry season affects milk composition, body weight gain, and weaning weight of their progeny. Milk yield and composition, and progeny postnatal growth performance, were recorded weekly. One week after kidding, mixed-breed goats (a mixture of Criollo × dairy breeds; n = 40) were allotted into medium (MP) or low (LP) milk yielding groups (20 goats per group). Mean 105-d total milk yield for MP and LP goats was 45.2 ± 12.5 and 20.7 ± 5.2 L, respectively. Milk lactose (4.3 vs. 4.2%) and solids-non-fat (SNF; 8.2 vs. 8.0) differed (p < 0.05) between MP and LP goats; milk protein content tended to differ (p = 0.08) between MP and LP goats with no difference for milk fat content (p > 0.05). Maternal body weight was positively associated with milk yield, milk lactose, and SNF content (p < 0.05 to p < 0.001). Goats giving birth to males produce more milk than goats giving birth to females, but milk fat percentage was higher in goats bearing females (p < 0.001). Milk yield and composition throughout lactation did not influence body weight gain (47.8 vs. 48.7 g/day for kids from MP and LP goats) and weaning weight (6.7 vs. 6.7 kg from MP and LP goats) of the offspring (p > 0.05). Birth weight and weaning weight of the progeny were positively related to maternal body weight (p ≤ 0.05). The postnatal growth of the kids was reduced, extending the time to reach market weight. Nevertheless, non-supplemented mixed-breed goats reared on semi-arid rangeland of northern Mexico have the potential for moderate milk production. Therefore, due to the limited nutrients ingested by grazing goats during the dry season, a nutritional supplement is necessary to keep up milk production and adequate growth of kids.

Periconceptional nutrition with spineless cactus (Opuntia ficus-indica) improves metabolomic profiles and pregnancy outcomes in sheep.

We tested whether periconceptional nutrition with cladodes from the cactus, Opuntia ficus-indica, with or without protein-enrichment, improved the metabolomic profile and reproductive outcomes of adult female sheep. Sixty Rambouillet ewes of similar body weight were randomly allocated among three nutritional treatments that were fed during the breeding period (34 days): Control (Control; n = 20), Opuntia (Opuntia; n = 20) and protein-enriched Opuntia (E-Opuntia; n = 20). There were no effects of treatment on body weight but assessment of urine samples indicated that, for 76 metabolites, the Control and Opuntia groups differed completely (P < 0.05), whereas there was overlap between the Control and E-Opuntia groups. It appears that, in Opuntia-fed and Control-fed sheep, different functional groups are activated leading to changes in the metabolism of glucose, tyrosine, methane, and glycerolipids. Fertility and reproductive rate tended to be higher in the Opuntia (70% and 95%) and E-Opuntia (90% and 110%) groups than in the Control (55% and 65%), and an orthogonal contrast revealed the difference between Control and Opuntia to be significant for both reproductive variables (P < 0.05). We conclude that nutritional supplementation with Opuntia cladodes, with or without protein enrichment, increased fertility rate and reproductive rate of female sheep, without any accompanying increases in body weight. Our observations suggest that the reproductive responses to Opuntia do not simply reflect a response to good nutrition, but might be caused by specific metabolites/metabolomic pathways, perhaps by an activation of the metabolism of glucose, methane, tyrosine and glycerolipids. There are few reports relating these metabolomic compounds with the metabolism of the sheep, let alone with reproductive efficiency. The novelty of these discoveries suggests that we need further research into the mechanisms through which nutrition affects the reproductive system.

Energy Supplementation during the Last Third of Gestation Improves Mother-Young Bonding in Goats.

We tested whether maternal energy supplementation during the last third of gestation improves birth weight, neonatal wellbeing, and mother-young bonding. Thirty-six pregnant French Alpine goats were randomly allocated among three nutritional treatments for the last third of pregnancy: (i) Control, fed alfalfa (T-0; n = 12); (ii) alfalfa + 150 g/head daily energy concentrate (T-150; n = 12); (iii) alfalfa + 300 g/head daily energy concentrate (T-300; n = 12). At birth, we collected progeny data on birth weight, birth type, sex, rectal temperature, heart rate, respiratory rate, time to standing, time to udder connection, and time to first feeding. For the dams, we collected data on the duration of labor, time to clean the progeny, and time to allow first suckling. At birth, body weight, rectal temperature, heart rate, and the respiratory rate did not differ among treatments (p > 0.05). In the dams, labor duration was not affected by the treatments (p > 0.05). The T-150 dams were faster to clean the newborn and allow first suckling (p < 0.05). The T-150 progeny were faster to stand and the T-300 progeny were faster to connect to the udder (p < 0.05). We conclude that energy supplementation of the dam during the last third of gestation does not affect the birth weight of the progeny, but enhances the mother-young bonding.

Pregnancy and Litter Size, But Not Lamb Sex, Affect Feed Intake and Wool Production by Merino-Type Ewes.

Two experiments (Australia and Mexico) tested whether feed intake (FI) and wool production (WP) are affected by pregnancy (PRG), litter size (LZ), or lamb sex (LS) in Merino-type ewes. In Experiment-1, ewes were either not pregnant (NPR; n = 6), or carrying 1 (PR1; n = 7) or 3 (PR3; n = 11) fetuses, were studied in individual pens. NPR ewes had lower (p < 0.02) FI throughout PRG and lactation (LAC), except around lambing (p < 0.001). Following lambing, FI increased in PRG ewes (p < 0.001) to double the values in NPR ewes. PRG reduced WP (p < 0.001); in PR3, WP was lower than for both PR1 and NPR (p < 0.001). WP decreased during LAC and was lower in ewes rearing lambs than in NPR ewes (p < 0.001). Experiment-2 used 48 pregnant ewes (28 bearing singles and 20 bearing twins). Dam and lamb live weights (LW) and body condition (BC) were recorded from birth to weaning at 60 d, and dam fleece weight (DFW) was measured at weaning (12 months growth). WP was higher in ewes bearing and rearing single lambs than in ewes bearing twins (p < 0.001). DFW was positively (p < 0.01) related to LZ, dam LW, and BC, but not to changes in dam LW during LAC, or to lamb weight at birth or weaning, or LW gain, or LS. In conclusion, FI was affected during PRG and by LZ during LAC, whereas WP was influenced by LZ, but not LS, only during pregnancy.