Productive performance and reproductive characteristics of Morada Nova male lambs fed with high-energy diet

• Published in: Tropical animal health and production Vol. 51; no. 8; pp. 2481 - 2491
• Main Authors: do Nascimento Barreto, Andréa, Guimarães Maciel e Silva, André, Esteves, Sergio Novita, Jacinto, Manuel Antonio Chagas, Barioni Junior, Waldomiro, Brandão, Felipe Zandonadi, de Andrade Pantoja, Messy Hannear, Botta, Daniela, Romanello, Narian, Lemes, Amanda Prudêncio, Giro, Alessandro, Garcia, Alexandre Rossetto
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01-11-2019; Springer Nature B.V
• Subjects: Animal Feed - analysis; Animal Nutritional Physiological Phenomena; Animals; Biomedical and Life Sciences; Body length; Body Weight; Defects; Diet; Diet - veterinary; Energy; Energy Intake; Energy Metabolism; Epithelium; Flux density; Life Sciences; Male; Males; Meat; Regular Articles; Reproduction; Scrotum - growth & development; Sheep; Sheep - growth & development; Skin; Testes; Testis - growth & development; Testosterone; Thorax; Tubules; Veterinary Medicine/Veterinary Science; Wool; Zoology; Performance; Morphometry; Hair sheep; Sperm; Ovis aries
• DOI: 10.1007/s11250-019-01969-0
• EISSN: 1573-7438
• ISSN: 0049-4747

Morada Nova breed sheep are without wool, tropicalized, small-sized animals, known for their high-quality meat and skin. Their body development naturally depends on the genetic potential and adequate nutritional support, which suggests that the offer of high-energy density diets positively influences their productive indicators. Thus, the present study investigated the effect of a high-energy diet for the Morada Nova lambs on body development and testicular function, considering their histomorphometric characteristics and seminal quality. Forty-two males (19.2 weeks, 20.7 ± 3.5 kg) were equally divided into two groups and fed with 2.05 Mcal (G7,
n
 = 21) or 2.37 Mcal (G24,
n
 = 21) of metabolizable energy/day, equivalent to 7% and 24% above the minimum for growing lambs. The animals were confined for 23 weeks (W0 to W23). Weight and body score differed significantly from the W1 (
P
 < 0.05). From the W5, thoracic perimeter, body length, wither height, and rump attributes were higher in G24 (
P
 < 0.05). The scrotal circumference and testicular volume were higher in G24 from the W3 (
P
 < 0.05). Although testosterone levels were not affected (
P
 = 0.05), the highest energy intake increased the diameter of the seminiferous tubules and the development of the epididymal epithelium (
P
 < 0.05). This positively influenced the seminal quality and reduced the minor defects (21.87% vs. 17.13%) and the total spermatic defects (26.34% vs. 21.78%,
P
 < 0.05). Thus, it is possible to employ higher levels of dietary energy for Morada Nova young males to express higher productive efficiency and earlier reproductive attributes of interest.