The effects of differing nutritional levels and body condition score on scrotal circumference, motility, and morphology of bovine sperm.

Bulls often experience various levels of nutrient availability throughout the year. Nutritional management is a critical factor on overall ejaculate composition and the ability to get females pregnant. We hypothesized that differing nutritional levels and body condition score (BCS) affect reproductive fertility parameters in bulls. Mature Angus bulls (n = 11) were individually housed and randomly assigned to one of two dietary regimens: 1) over-fed (n = 5) or 2) restricted (n = 6). Bulls were fed the same ration at different volumes to achieve desired effects resulting in eight individual treatments: gain to an over-fed body condition score ([BCS]; GO), gain after nutrient restriction (GR), loss after an over-fed BCS (LO), loss from nutrient restriction (LR), maintenance at ideal adiposity (BCS = 6) after overfeeding (IMO), maintenance at ideal adiposity after nutrient restriction (IMR), maintenance at an over-fed BCS (BCS = 8; MO), and maintenance at a restricted BCS (BCS = 4; MR). Body weight (BW) and BCS were recorded every 2 wk to monitor bull weight and BCS changes. Scrotal circumference was measured every 28 d. Body fat and sperm motility and morphology were evaluated every 84 d. Scrotal circumference, motility, and morphology were normalized to the initial value of each bull. Thus, allowing the individual bull to serve as a control. Statistical analyses were conducted with PROC GLIMMIX of SAS as a complete randomized design to determine if treatment influenced BW, BCS, scrotal circumference, motility, morphology, and adipose thickness. Scrotal circumference (P < 0.001) had the least amount of deviation from initial during the LR (0.29 ±â€…0.44) treatment and the greatest during the MO (3.06 ±â€…0.44), LO (2.28 ±â€…0.44), MR (2.43 ±â€…0.44), GR (3.03 ±â€…0.44), and IMR (2.91 ±â€…0.44) treatments. Sperm motility was not affected by nutritional treatments (P = 0.55). Both head and total defects of sperm differed (P = 0.02) due to nutritional treatments. Increased head abnormalities occurred during the LO (37.60 ±â€…8.61) treatment, with no differences between the other treatments. Total defects increased during the LO (43.80 ±â€…9.55) treatment with similar increases in bulls during the GR (29.40 ±â€…9.55) and IMR (35.60 ±â€…9.55) treatments. In conclusion, male fertility was impacted when a deviation from a BCS of 6 occurred which could be detrimental to reproductive and beef production efficiency.

Ingredients derived from the slaughter of bovines in dog food / Ingredientes provenientes do abate de bovinos em alimento para cães

ABSTRACT: This study evaluated the nutritional levels, apparent digestibility coefficients, and faecal characteristics of dogs fed with four by-products from bovine slaughter: testicles, residue sirloin steak, trachea, and liver. Ingredients were processed and packed in tins for heat treatment in autoclaves. For the digestibility and faeces quality, ingredients were mixed with a reference diet (commercial food) in the proportion of 30g kg-1 test ingredient and 70g kg-1 reference diet (as dry matter). Ten adult dogs were distributed in double Latin block squares (5x5) with five treatments and five periods, totalling ten repetitions per treatment. The residue sirloin steak presented the highest levels of essential (414.2g kg-1 of dry matter) and non-essential (399.0g kg-1 of dry matter) amino acids in tested ingredients. No differences (P>0.05) were observed in apparent digestibility coefficients of dry matter - ADCDM (907g kg-1), ADCOM (930g kg-1), ADCCP (841g kg-1), ADCAEE (954g kg-1) values, and DE (5069kcal kg-1) and ME (4781kcal kg-1) values between testicle, residue sirloin steak, and liver. The trachea presented lower digestibility and energy values (digestible and metabolizable) than the other ingredients. This lower trachea digestibility resulted in higher faecal volume for natural and dry matter (P<0.05). There was no difference (P>0.05) in faecal score between ingredients. Ingredients tested in this study can be used in feeds for adult dogs; however, their nutritional levels and digestibility values should be considered for correct diet balance.

RESUMO: Foram avaliados os níveis nutricionais, coeficientes de digestibilidade aparente e características das fezes de cães alimentados com quatro ingredientes provenientes do abate de bovinos: testículo, apara de contra filé, traqueia e fígado. Os ingredientes foram processados e acondicionados em latas para tratamento térmico em autoclaves. Para o teste de digestibilidade e características das fezes os ingredientes foram misturados a uma dieta referência (alimento comercial) na proporção de 30g kg-1 do ingrediente teste e 70g kg-1 da dieta referência (base matéria seca). Dez cães adultos foram distribuídos em delineamento quadrado latino duplo (5x5), com cinco tratamentos e cinco períodos, totalizando dez repetições por tratamento. A apara de contra filé apresentou os maiores níveis de aminoácidos essenciais (414,2g kg-1 de matéria seca) e não essenciais (399,0g kg-1 de matéria seca) entre os alimentos avaliados. Não houve diferença (P>0,05) nos valores do coeficiente de digestibilidade aparente para matéria seca - MS (907g kg-1), MO (930g kg-1), PB (841g kg-1), EEA (954g kg-1), e os valores de ED (5069kcal kg-1) e EM (4781kcal kg-1) entre testículo, apara de contra filé e fígado. A traqueia apresentou os menores valores de digestibilidade e energia (digestível e metabolizável) entre os alimentos testados. A menor digestibilidade da traqueia resultou em maior volume de fezes na matéria natural e seca (P<0,05). Não houve diferença (P>0,05) no escore fecal entre os alimentos. Os ingredientes avaliados no presente estudo podem ser utilizados na alimentação de cães adultos, porém deve-se considerar os seus níveis nutricionais e os valores de digestibilidade para o correto balanceamento das rações.